ASPHALTopics Summer 2023

BLUE WATER BRIDGE

26 years of asphalt performance

WARM MIX ASPHALT

production and placement

EXCESS

SOIL

practical solutions for planning

The official publication of the Ontario Asphalt Pavement Council, ASPHALTopics is published three times a year.

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Patricia Abbas | 416.438.7609 | pabbas8@gmail.com

EDITOR

Lara Henry | larahenry@sympatico.ca

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COVER

CHAIR’s CORNER

Peter Hamstra Chair

Sustainability and quality

Sustainability is a word that you read and hear about almost everywhere you turn these days. A dictionary definition search of the word ‘sustainability’ that resonates with me the best is this: “ Sustainability consists of fulfilling the needs of current generations without compromising the needs of future generations, while ensuring a balance between economic growth, environmental care and social well-being.”

OAPC has identified sustainability as a key pillar of its vision and mission. As an industry, we must continue to view sustainability as being tied to quality. The two cannot be separated. A sustainable asphalt pavement must be made to last. I cannot over emphasise this enough. The balance between economic growth, environmental care and social well being must link quality and sustainability together.

Each year, OAPC continues to invest tens of thousands of dollars into research of new and existing technologies to help us design and produce quality and sustainable asphalt pavements. We are looking forward to building a strong partnership with the National Research Council Canada as we develop a Sustainability Action Plan in the years to come. Recently at our Spring Operations Seminar and the Partners in Quality Road Tour, several of the key presentations surrounded the topic of sustainability, from energy efficiency ideas at the plant, to alternative and renewable fuels, to Environmental Product Declarations, to greenhouse gas reductions.

OAPC is committed to leading its members through research and education on these critical topics. Our members must all share this common desire to build quality, sustainable pavements that last and that we can be proud of.

The ongoing work of reviewing code, standard and specification updates is another one of OAPC’s strategic priorities. The work of the OAPC-MTO Hot Mix Paving Technical Committee is a critical part of how that priority gets delivered.

Along with the work done by the Hot Mix Asphalt Technical Working Group, these committees bring together the industries best technical people in an effort to drive our quality and sustainability goals.

The ORBA Board is currently in the middle of reworking its five-year strategic plan. In my role as OAPC chair, I also have a seat on the ORBA Board and I am participating on the Strategic Planning Committee. I am excited to see that the five strategic priorities that OAPC has developed will be reflected and supported by the new ORBA strategic plan. I look forward to our continued strengthening relationship with ORBA as an amalgamated association. We are a strong voice as we work together to support and promote the priorities of OAPC/ORBA.

A great example of this was shown recently at our Queen’s Park Lobby Day. Over 30 delegates from OAPC and ORBA boards and staff spent a day at Queen’s Park meeting with various MPPs, the cabinet minister and key staff members to promote key issues that face our industry. Some of the main discussion points were the need for strong investment in transportation infrastructure supported by early tender calls, labour shortages, promoting the use of recycled materials, and the need for material indices in municipal contracts. As a strong amalgamated association, we were able to get our message out in a powerful and effective way.

It’s a privilege to serve on the OAPC Board with so many knowledgeable and passionate members of our council. If you have any suggestions or comments, or would like to get involved in any way, please reach out. Keep an eye out for more upcoming educational opportunities that OAPC will be hosting including webinars and the ever-popular Fall Asphalt Seminar. I also look forward to seeing many of you at our upcoming Annual Golf Tournament in August. Take care and be safe.

OPERATIONS CORNER

Doubra C. Ambaiowei Director, Technical Services

Engaging for the greater value of asphalt in Ontario

Welcome to the summer edition of ASPHALTopics. In the words of Oprah Winfrey, “Summer has a flavor like no other; always fresh and simmered in sunshine.” For us in the asphalt paving and road building industry, we connect positively with the summer months. It’s the best time for paving for a variety of reasons ranging from longer setting times through greater stability, better operational planning and more.

Despite the demands of summertime, industry stakeholders across all levels of responsibility found the time to meet with municipal and provincial road owners as well as academic collaborators on June 13 for OAPC’s fifth annual Asphalt Technical Symposium (ATS). The ensuing dialogue built on conversations and standing objectives exploring the continuing focus on asphalt binder challenges, solutions, and pathways for mix performance testing in Ontario, with particular focus on the Ontario-Mix Asphalt Program (O-MAP) round two study findings, and OAPC’s continuing mandate to encourage the use of Reclaimed Asphalt Pavement (RAP). You can access the 2023 OAPC ATS presentations on the OAPC website. A recap of the event will be part of the 2023 OAPC Fall Asphalt Seminar scheduled for Thursday, November 30.

Leading up to summer, on April 18 OAPC pushed forward its objectives on environmental stewardship and quality asphalt in Ontario by engaging with municipal road owners at the 2023 Good Roads Conference and educating them about the Trillium Award Program. To date, 103 asphalt plants have earned the Trillium Award and 147 award renewals have been issued. With a high percentage of asphalt plants now Trillium awarded over the last 20 years, OAPC is evaluating its options on increasing the value of this award for its members and the municipalities they serve. Stakeholder dialogue has shown that “focusing on quality outcomes, seeking ways to restore confidence, and collaborating on RAP pilot projects to further the success of experiences that show the durability of HMA is not compromised by incorporating

and/or increasing the amount of RAP that is currently allowed” are important considerations.

Based on a recent OAPC survey, about 86 per cent of respondents see value in knowing that their local asphalt plants are Trillium awarded, while 75 per cent of respondents indicate that they would consider mandating or applying for the award in its current self-regulated form while partnering the OAPC to improve the program requirements. If you have yet to respond to our Trillium Award Program survey, please do so here or by scanning the QR Code below:

Applications for the 2023 OAPC Trillium Award Program close on Friday, October 27. The application form can be accessed here.

We extend a special thanks to members of the Ontario Asphalt Expert Task Group (OAETG), Industry’s High RAP Literature Review Working Group, and our partners at MTO. The engagement, unbiased dialogue, opportunity to educate ourselves, and dedication from these industry groups and our provincial and municipal partners complement OAPC’s objectives to promote quality and sustainable asphalt products and paving techniques in Ontario. These efforts further improve our readiness to implement research-study findings, achieve value for money in delivering better pavement solutions, and bring greater transparency to our collaborative processes.

This summer edition of ASPHALTopics places emphasis on asphalt’s performance – making it the pavement of choice. We also spotlight the Good Roads-OAPC Municipal HMA Paving Awards, and recap the 2023 OAPC Spring Operations Seminar and Partners in Quality Road Tour. You should not skip the environment, technical, marketing, and last word columns.

Please enjoy the contents of this summer edition of your favourite ASPHALTopics magazine and endeavour to make the most of SUMMER.

MARCOM MATTERS

Guru Missar Director, Marketing & Communications

Building brands for sustained success

In the fast-paced world of business-to-business (B2B) marketing, it’s easy to focus on immediate results rather than the potential for long-term growth that brand building offers. While brand building may be challenging and requires greater investment, its long-term impact on growth and profitability cannot be ignored.

In the asphalt industry, where logical decision-making processes often drive B2B purchases, the temptation to prioritize sales activation, i.e. when the customer decides to purchase, over brand building may be strong. However, it is crucial to recognize that brand building plays a vital role in influencing long-term growth and profit. By establishing emotional connections and fostering trust, brand building reduces price sensitivity and enhances margins, leading to increased customer loyalty.

Brand building and sales activation work hand in hand, complementing each other to maximize the effectiveness of marketing efforts. Strong brands enjoy higher sales resulting in increased profitability. However, striking the right balance between brand building and activation can be challenging as they operate in different ways and over different timescales. Activation effects, although immediate and measurable, tend to produce short-term sales spikes. Brand effects,

although harder to measure in the short term, gradually increase the base level of sales, driving long-term growth.

During times of economic uncertainty, organizations often reduce marketing budgets as a short-term cost-saving measure. This may seem logical on the surface but can be detrimental to the long-term health of the business. It is during these uncertain times that investing in marketing, particularly brand building, can yield significant dividends. Why? Because as other organizations retreat, your brand can stand out, fostering trust and establishing lasting associations that pave the way for sustained growth and profitability when the economy rebounds.

A balanced approach is key, considering both long and short-term effects to optimize the marketing mix. Research, such as that conducted by the Institute of Practitioners in Advertising, suggests that allocating around 60 per cent of the communications budget to brand building and 40 per cent to activation yields optimal results — the ‘60:40 rule’.

The implications for channel strategy in the asphalt industry are significant. Sales activation works best when targeted at those likely to make immediate purchases using informationrich media and rational messages. On the other hand, brand building requires broad-reach media, repeated exposures, and emotional priming to create lasting associations and connections. A comprehensive evaluation of both short and long-term effects is essential to develop an effective marketing strategy that balances brand building and sales activation.

As an industry publication, ASPHALTopics magazine offers an unparalleled platform for businesses in the asphalt industry. By leveraging the magazine’s reach and engaging content, companies can make strides in applying the 60:40 rule to their marketing efforts. Remember, a balanced marketing approach that strategically combines brand building and sales activation is the key to achieving sustained success.

26 years

Long-lasting asphalt performance on Blue Water Bridge

(Federal Bridge Corporation)

by James Careless

The three-lane second Blue Water Bridge, which is a continuous tied arch bridge with a total length of 1.85 km and a main span of 451 m, was built alongside the first Blue Water Bridge, which opened in 1938. On average, about 14,000 vehicles cross the two bridges daily, including 6,000 trucks.

Much has changed since the second Blue Water Bridge opened 26 years ago, but what hasn’t changed is the asphalt surface on the bridge’s concrete deck. The two lifts of asphalt (a 20 mm binder course lift and a 35 mm surface course lift) have endured an incredible volume of vehicles over the years without needing to be replaced until now.

“We do maintain the bridges really well,” says Rubara Chowdhury, Senior Project Engineer with the Federal Bridge Corporation Limited, the crown corporation that manages international bridges in Canada. (U.S. agencies manage the U.S. sides of international bridges.) “If there is a pothole that forms, we deal with it in a timely manner. Still, the original asphalt has stood up well after many years of service.”

The Original Mix Design

According to Doug Woods, Construction Manager with Cope Construction at the time, Ellis Don served as the primary contractor of the approach spans as well as the paving of the Canadian side of the second Blue Water Bridge project. “I was the estimator responsible for putting the original tender together as a subcontractor,” he says. “We hired Ashwarren Engineering Services to help us review and prepare the asphalt mix designs. We were familiar with them through our relationship with OHMPA, now OAPC.”

Paul Lum, Technical Director with Colas USA, was an Ashwarren manager back in 1997. “Cope Construction hired our company to perform the mix design work for them so that they could pave the project to the contract specifications which had been prepared by the bridge designers Modjeski and Masters (American side) and Buckland & Taylor Ltd. (Canadian side).” ››

In 1997, the second Blue Water Bridge was opened. Spanning the St. Clair River, the bridge connects the city of Sarnia, Ontario to the U.S. city of Port Huron, Michigan.

The same lay down and compaction equipment was used for the surface course as for the binder course. The surface course was more compactable requiring four passes each by the breakdown and intermediate rollers, followed by two passes by thefinishing roller to achieve a 93% compaction. (Doug Woods, 1997)

According to an article about the project written afterwards by Lum and then Cope Construction president John Williams entitled Paving of the Second Blue Water Bridge and Failures During Construction, the contract specifications for both the Ontario and Michigan road surface – including the waterproofing system and flexible pavement – were similar.

Both called for a base layer of polyester fabric sandwiched between two layers of hot-poured rubberized asphalt to a thickness of 5 mm on the bridge’s concrete deck. This was then covered by a sheet of No. 8 paper, 20 mm of High Stability HL 2 binder course mix and 35 mm of Modified HL 1 surface course mix, all of which was specified in the contract.

According to Woods, the specification for 55 mm of total asphalt surfacing was a deliberate choice. “The asphalt was viewed as a wearing surface rather than a road in line with the bridge designers’ goal of not adding any more ‘dead load’ (the weight of the bridge’s permanent non-moving elements) to the structure than they had to,” he says. “In fact, the concrete deck and asphalt paving were probably 25 to 30 per cent thinner on the second Blue Water Bridge than they were on the first.”

Creating the High Stability HL 2 mix brought challenges of its own. Cope Construction’s goal was for this mix to achieve a minimum stability of 16,000 N (Newtons). To meet this target, Cope Construction used an aggregate mix of 35 per cent 3/8 inch chips and 54.2 per cent manufactured sand from Redland Quarries, plus 10.8 per cent screenings from Michigan Limestone. But “even though 100 per cent quarried aggregates were used in the mix design, the stability of the mix did not meet the minimum specified requirements and the final blended aggregate Job Mix Formula (JMF) did not meet the overall gradation band,” says the Lum/Williams article.

The problem was the HL 2 specification which had been achieved on a previous

Photos –Doug Woods.

bridge project using a coarse aggregate made out of blast furnace slag and an asphalt cement “heavily modified with polymer,” continues the Lum/Williams article. “The contractor offered to use those materials in order to meet the stability requirements for this contract. But, due to the increase in cost for those materials, the bridge’s consultant elected to reduce the minimum required stability to 14,000 N and approved the initial HL 2 (HS) Mix design.” As it turned out, the final HL 2 aggregate blend had a stability level of 14,6000 N, with asphalt cement making up 6.4 per cent of the total mix.

Fortunately, the Modified HL 1 surface course mix didn’t run into any issues. Its aggregate mix consisted of 41 per cent HL 1 stone from Smelter Bay Aggregates, 35.4 per cent asphalt sand from Lafarge, and 23.6 per cent screenings from Michigan Limestone. This top layer had a stability rating of 11,670 N, with asphalt cement accounting for 5.2 per cent of the completed hot mix.

The Original Application Method

While the second Blue Water Bridge’s original mix design played a big role in its 26 year record of durability, the way in which this asphalt was applied to the concrete deck also made a difference.

Two weeks were allocated for waterproofing and paving the second Blue Water Bridge’s concrete deck, with the work starting on May 14, 1997. Initially, a rubber tire asphalt paver had been specified to minimize damage to the water proofing system, but Cope Construction suggested using a rubber tracked crawler paver instead “since it would have lower ground pressure than a rubber tire paver,” says the Lum/ Williams article. “The force required to propel the paver and to push a loaded truck uphill would also be lower.”

A Blaw-Knox PF 410 crawler paver equipped with an Omni 1AS extendable screed was used instead of the rubber tire paver. This combination “operated satisfactorily with no damage to the waterproofing system,” the Lum/Williams article says.

The HL 2 course was laid in two lengthwise passes of 3.2 m each, followed by two more passes of 3.4 m each, for a total width of the combined four passes of 13.2 m between the bridge’s two curbs, all done in an uphill direction. “The breakdown roller was a Bomag BW 151AD double drum steel roller, the intermediate roller was a Caterpillar PS180, 9-tire pneumatic tire roller, and the finishing roller was a Dynapac CC142 double drum roller,” says the Lum/Williams article. A second CC142 was used for transverse rolling at the bridge joints.

On the first day of paving, the low ambient temperature on the bridge (about 7°C) combined with cool winds blowing off Lake Huron, meant that there was only about two minutes for the rollers to achieve the specified 93 per cent compaction. ››

On the first day of paving, the low ambient temperature on the bridge (about 7°C) combined with cool winds blowing off Lake Huron, meant that there was only about two minutes for the rollers to achieve the specified 93 per cent compaction.

To make matters worse, “it was found necessary to run the paver at the lowest possible speed in order to minimize the area of mat exposed, and to maintain the mat temperature as high as possible. Use of the screed vibrators did not prove beneficial and in fact reduced the mat compaction as determined by using a thin lift nuclear gauge and rolling compaction test strips,” says the Lum/Williams article.

Once the HL 2 binder course had been laid down, it took six passes by the breakdown roller, six passes by the intermediate roller, and two passes by the finishing roller to achieve the required 93 per cent compaction. All of the rollers operated in static mode due to concerns that vibrations could cause micro-cracking in the bridge’s concrete deck.

The weather warmed up to 12°C on May 20 and 21, 1997, when the rest of the HL 2 paving was completed. But variable cloud cover caused the deck temperature to vary between 19 and 42 degrees Celsius.

The 35 mm Modified HL 1 surface course was laid on May 22 and 23. This was done uphill in three passes of 4.8 m, 3.6 m and 4.8 m. These widths were chosen so that the longitudinal joints would align with the planned traffic lane markings.

“The same lay down and compaction equipment was used for the surface course as for the binder course but this layer was more easily compactable,” the Lum/Williams article notes. As such, it only required four passes each by the breakdown and intermediate rollers, followed by two passes by the finishing roller, to achieve a 93 per cent compaction rate.

Dealing with Unexpected Issues

“What we experienced was the fact that, when we had a truck parked waiting for its turn to load the paver for the HL 1 course, cracks would appear underneath the rear axle where the majority of the load was,” says Woods. “When temperatures got up over 30°C on the pavement surface, we started seeing indentation and cracking on the upside of the rear tandem trucks that were fully loaded with hot mix,” Lum adds. This problem was resolved by keeping the truck moving forward slowly in front of the paver. But why had the trucks’ rear wheels caused cracks in the HL 2 course at all? Some were serious: “The worst failure showed a crack approximately 12 mm wide on the uphill side and the asphalt was shoved up approximately 25 mm high on the downhill side of the tire footprint,” the Lum/Williams article says.

Rigorous quality control testing by Cope and Ashwarren eventually revealed the culprit: The 5 mm sandwich of paper and rubberized asphalt providing waterproofing between the concrete bridge deck below and the 55 mm of asphalt cement above. When the bridge surface got too hot, the waterproofing layer could be deformed or moved by heavy truck weight pressing down on the asphalt pavement, resulting in cracks and other issues.

“The deck temperature at the time of the failures was 42°C,” says the Lum/ Williams article. “There had been no problem in the morning when the deck temperature was in the range of 20 to 25°C.”

Once the cause of the problem had been discovered, Cope and Ashwarren weighed their options and the associated costs, from repairing the damage to adding plastic geogrid or steel expanded metal between the concrete deck and the asphalt lifts.

“Here’s the crazy thing,” says Lum. “The areas that slipped, we repaired the asphalt in those areas and that was it. Then we waited and the problems did not recur. We stopped them on the job site by keeping the trucks moving. Once the bridge was open to traffic, it kept moving and the cracks didn’t happen again.”

From then until now, the asphalt pavement on the second Blue Water Bridge has held up. Whether its planned replacement – 50 mm of Superpave 12.5 FC2 – does as well remains to be seen. That work will begin next year, says Chowdhury, because 26 years of relentless use has finally taken its toll. And yes, asphalt was chosen for the new surface “due to the way the original asphalt performed,” she says.

James Careless is an Ottawa-based freelance writer with credits in the National Post, Toronto Star, and AI’s Asphalt magazine.

Photos –Doug Woods.

Asphalt was chosen for the new bridge surface “due to the way the original asphalt performed.”

RUBARA CHOWDHURY Federal Bridge Corporation

Asphalt production and laydown, energy efficiency and WMA highlights at Spring Operations Seminar

This year’s OAPC Spring Operations Seminar on March 23 brought together industry leaders and stakeholders to discuss the latest technologies and best practices, and celebrate notable achievements.

Key sessions included an open dialogue with all participants on the operational and logistical challenges in asphalt production and laydown, an overview on programs and opportunities to help the asphalt industry be more energy efficient, and an update on warm mix asphalt implementation.

OAPC chair Peter Hamstra congratulated the 2022 Roads Scholarship Award winners and summarized OAPC’s strategic priorities for 2023. The OAPC plant safety excellence awards were presented followed by an overview of the Trillium Award Program and health and safety management programs.

Spring Operations Seminar presentations are available on the OAPC website and include the following:

• Overview (including award winners)

• Warm Mix Asphalt Implementation: Production and Placement Considerations – Tom Dziedziejko

• IHSA Presentation – David Steinschifter

• Towards Net-Zero: Energy Efficiency Considerations for the Asphalt Industry – Chris Russell

• Conestoga College Brantford Campus – Heavy Construction Equipment Operations (HCEO) Program – Reg Legere

The day concluded with a visit to the Conestoga College Brantford campus for lunch and an equipment show where the students provided a live demo of an asphalt laydown simulated with sand.

WARM MIX ASPHALT IMPLEMENTATION: Production & Placement Considerations

The use of warm mix additives to reduce the temperature of bituminous mix during paving is not a new concept. Warm mix additives have been available to the industry for over 15 years. At technical and industry conferences, the use of warm mix asphalt has regularly shown numerous benefits such as reduced plant emissions, reduced paving crew exposure to fumes, the improvement to overall pavement compaction, better joints, increased resistance to stripping, and the ability to pave in less than optimum weather conditions that would likely result in a poor outcome if the additive was not used.

urrent MTO contracts and many municipal contracts are permissive and allow the use of warm mix asphalt (WMA) at the mix suppliers’ option and cost. A large percentage of suppliers have tried the additives, but very few have carried the cost of the additives when bidding or incorporated their use in daily mix production. The concern is simple in that carrying the cost of the additives when bidding may increase the tender amount, and this cost increase may result in a competitor, who does not carry the additive, winning the job.

Senior MTO and industry leaders agree that the environmental benefits and increased pavement quality resulting from the use of the additives is highly desirable and a collaborative process was initiated to see warm mix used on all projects by specifying its use at tender. As part of this process, Special Provision BITU-00029 (SP), a specification for the mandatory use of warm mix additives, was developed by MTO and vetted by industry.

by Tom Dziedziejko

The primary intent of the SP is to control greenhouse gas emissions, level the bidding field, and reduce paving crew exposure to fumes. This specification is endorsed by senior MTO management as being preferred for future paving contracts. The intent is to see the eventual use of warm mix asphalt on all MTO paving contracts in the future, although a firm sunset date for the use of hot mix has not been committed to by MTO. Implementation of the specification is currently with the MTO regional offices, with implementation on projects based on benefit. The specification has been included in some projects tendered in 2022 and additional projects are expected this paving season.

Special Provision BITU-00029 overview

At a high level specification overview, the specification contains a list of approved warm mix additives. The current list of five additives is not considered an approved designated source (DSM) for the additives. Other additives may be added to the list in future.

Mix production temperatures, as measured at the plant discharge, are specified as a maximum of 135°C or 20°C below the production temperature of the mix without additives, not exceeding 150°C. Temperatures will be measured once per hour at the plant discharge and every 250 metres during paving. There is a grace period at the start of production that allows variance in temperature to a maximum of 15°C above the allowable production temperature. When production temperature exceeds the allowable temperature, the mix is non-conforming and a three per cent payment reduction will be applied.

The specification requires placement of a control section of the mix without the use of the warm mix additive. In addition to typical acceptance sampling, additional loose samples for moisture sensitivity testing and cores for performance testing, will be required. Environmental monitoring by an independent consultant may be required. Monitoring of plant stack emissions and paving crew fume exposure will be required for production for a designated number of sublots with the warm mix additive and without the additive. ››

SPRING OPERATIONS SEMINAR

Warm mix asphalt and compaction aids

In general discussion, technical presentations, and articles on the use of warm mix additives, it is not unusual for the terms warm mix asphalt and compaction aid to be mentioned. A warm mix additive produces a warm mix asphalt and provides the benefit of acting as a compaction aid when the mix is produced at 20°C or more below normal production temperature for the mix without additive. However, the temperature at which the mix is produced limits how these terms are applied when dealing with the additives and the new specification.

When a mix is produced at normal hot mix temperatures, or at a temperature of less than 20°C below normal production temperature, the use of the additive is considered as a compaction aid ONLY. Mix produced in such a manner is treated as hot mix and is not considered a warm mix. Further, under the BITU-00029 Special Provision, the mix is subject to a 3 per cent payment reduction as its primary purpose is considered to be assisting in achieving density. Regardless, there are situations, such as paving in cold conditions, where the paving crew may need to weigh the cost of increasing the plant temperature against the cost of potential payment reductions that may be applied for not achieving the specified compaction of the mix.

The lower plant temperatures required when producing a warm mix asphalt do create some production challenges. Aggregate moisture will impact plant production rate and plant operators will need to implement new procedures as a result. Good stock pile drainage will be required and covering stockpiles may be required to assist in reducing moisture impacts. Plant burner optimization should be considered, and with some older plants, flight modifications may assist in increasing efficiency.

The environmental benefits of using a warm mix additive are significant and of interest to owners and suppliers alike. Compaction aid benefits are equally important and regularly reference improved joints and a tighter mat. Understanding why these benefits occur can help paving contractors produce a higher quality product, implement cost saving placement techniques, and can help avoid payment reductions.

How warm mix additives work

The currently approved warm mix additives have their own unique properties, but effectively they work on similar principles. The additives polarize certain molecules in the AC thereby reducing the surface tension of the AC without significant impact to the AC viscosity. This allows a more consistent coating of the aggregate and the warm mix tends to compact more easily. Using a warm mix additive and the same placement and rolling procedures used with hot mix

should result in better compaction. However, taking the time to understand the differences between warm mix and hot mix allows the paving crew to produce a much higher quality product and potentially apply certain cost saving procedures. Compaction trial strips correlated to pavement temperature and weather conditions should be completed to allow crews to understand their production limits. Understanding the additional time available for compaction allows modifying haulage and rolling patterns.

Using warm mix additives not only reduces the required production temperature of a mix but also reduces the lower temperature at which the mix can be compacted. In this way, mat heat loss impacts (i.e. rapid cooling of joints, general heat segregation across the mat), that hinder compaction are reduced, allowing better joints and an overall tighter and better compacted mat. The ability of a warm mix additive to reduce the temperature that a mix can be compacted also translates in to a significant time period available for compaction of the mix in comparison to a hot mix. The additional time is made available in part by the fact that the hotter an item is in comparison to its surrounding temperature, the faster the rate of cooling of that item will be.

Warm mixes therefore cool more slowly than hot mixes due to the smaller temperature difference between the ambient temperature and the mix. In addition, warm mix additives reduce the minimum temperature at which rolling of the mat should be stopped. The Minnesota Department of Transportation (DOT) has an APP available for download on their website free of charge. The APP estimates the time available for compaction of a mix based on the weather conditions, mix location within the pavement, and substrate type. Inputting the temperatures at which rolling is started and stopped produces an estimate of the time available for compaction.

Anti-stripping resistance

Some warm mix additives provide anti stripping resistance when moisture sensitive aggregates are used in a mix. In Ontario, an anti-stripping treatment is required if the tensile strength ratio of the mix is less than 80 per cent. However, in northern Ontario, an anti-stripping treatment is required on MTO projects for all mixes placed regardless of TSR value. Using an anti-stripping treatment plus a different warm mix additive results in a cost increase for the mix as two additives are being used. Using one additive to provide both stripping resistance and warm mix properties would be the most cost effective.

While Special Provision BITU-0029 currently lists five approved WMA additives, only three additives, Evotherm M1, WarmGrip N1, and Zycotherm SP2, are approved for use as anti-stripping treatments (AST-AC) in MTO DSM 3.05.10. Mix suppliers should review their options for use of warm mix additives and anti-stripping treatments to determine the additives that best suit their operations. As with all chemical use, safety data sheets should be reviewed to ensure their preferred additive meets their company health and safety goals. AC suppliers typically supply the additives as part of their AC sales, but each supplier offers only certain additives. Requesting an additive that is not normally available through a supplier is possible. Alternatively, mix producers can opt to purchase the additives direct from the distributor and add them at their plants. However, the mix producer should be aware of any additional documenting and reporting requirements specified if this option is chosen. Further, special pump requirements and the need for special seals should be investigated.

Industry and senior MTO management support the use of WMA due to its many environmental benefits, quality enhancement ability, and improved compaction. Although a firm implementation date has not been announced by MTO, some contracts are underway or are in the process of being tendered with the new BITU-00029 Special Provision. Warm mix asphalt is expected to become the norm on paving contracts in the near future. Asphalt mix producers should become familiar with the advantages and impacts of using warm mix additives in their daily operations.

Tom Dziedziejko is the former Director of Quality, Infrastructure for Aecon Group Inc. and continues to work as a consultant in the industry.

Warm mix asphalt is expected to become the norm on paving contracts in the near future.

THE ANNUAL

The Municipal Paving Award recognizes and promotes the successful collaboration between municipalities and asphalt producers for excellence and innovation in Ontario paving projects.

Entries are judged on five criteria:

1. conformance of the finished paving to the project’s specifications based on physical testing;

2. the visual appearance of the project;

3. the quality of workmanship;

4. innovations used to execute the project; and

5. other considerations such as tight schedules, working at night, and dealing with traffic flow.

The award was created by the Municipal HMA Liaison Committee to promote excellence in Ontario paving practices and projects. The HMA Liaison Committee is an industry/government group that includes OAPC, Good Roads, construction firms, and Ontario municipal governments.

Previous paving award winners and finalists have received tremendous positive feedback on their excellence in paving and road building through exposure at events such as the Good Roads conference, in ASPHALTopics , and online. It’s a no-cost opportunity to showcase your achievements and highlight the benefits of effective collaboration in paving projects.

Don’t miss out on this opportunity to showcase your hard work and dedication towards excellence in paving. Collaborate with your fellow project counterpart (municipal/contractor), submit your project for the 2023 Municipal Paving Award, and celebrate your successful project team’s hard work.

VILLENEUVE CONSTRUCTION and TOWN OF HEARST

Villeneuve Construction won the first Municipal Paving Award for its outstanding work of paving a busy stretch of Front Street (Highway 11) in collaboration with the Town of Hearst. The Front Street project, which ran from 15th Street to 6th Street, involved extensive traffic management and was completed safely and ahead of schedule.

The company’s 35-plus crew were charged with performing full depth removal on Front Street, followed by frost heave treatment, curb and cutter replacement, and road rehabilitation.

They opted for warm mix asphalt (WMA) to pave Front Street using 5,700 tonnes of SP19.0 - Cat. C PG58-34P binder WMA, and 3,250 tonnes of SP12.5- Cat. C PG5834P surface WMA. This gave them better

The high calibre of the entrants and winners proves that Ontario’s asphalt industry has much to be proud of.

by Lara Henry

2017 Award Winner 2018 Award Winner

COCO PAVING and CITY OF TORONTO

Coco Paving Inc. won the second annual Municipal Paving Award for the company’s resurfacing of sections of the Gardiner Expressway’s elevated portion from November 3 to 4, 2018.

compactability at lower temperatures and a larger range of outdoor conditions to work in. They also used compaction rollers with Intelligent Compaction technology to achieve a more consistent, uniform road surface and overall finish.

Villeneuve Construction finished this project in 42 working days out of the contracted 50. This was no small achievement: the project had to be done while directing traffic from Highway 11 in and out of Hearst, and ensuring that the many businesses within the job site had constant access to the road.

The company credited the project’s success to good pre-planning, a focus on quality, and a dedicated workforce.

Since shutting down the Gardiner during the week was not possible, the City of Toronto decided to confine the milling and resurfacing of sections of the Gardiner to one single weekend. Coco Paving had to mill and resurface the Gardiner Expressway’s 6.8 km long elevated portion within that very tight time-frame, milling and paving the eastbound/westbound lanes and on/off ramps at the same time.

These two separate and simultaneous operations required the co-ordination of production between two asphalt plants and 100 trucks that supplied asphalt to the project and four large milling machines capable of collectively milling a minimum of 8,000 square metres of asphalt an hour.

After the milled asphalt had been removed and the HMA began to come in, eight paving crews worked to pave the surfaces in both directions. The HMA-filled trucks drove to the pavers, unloaded, then drove back to the plants at pre-planned exits. More than 20 Coco Paving quality control personnel worked on site to ensure consistency in the mix and compaction process. The City of Toronto required twice the usual number of tests to ensure consistent pavement conformance to specifications. Coco Paving operated two laboratories, and the City of Toronto one, to test 50 to 60 samples during the paving process. The company also brought in more than 150 labourers, equipment operators and supervisors from its operations across Eastern Canada in order to get the job done. ››

2019 Award Winner

PIONEER CONSTRUCTION and OLIVER PAIPOONGE

The $4.27 million project that won this year’s Municipal Paving Award for Pioneer Construction Inc. covered a 9.6 km stretch of Oliver Road in the Township of Oliver Paipoonge west of Thunder Bay.

Phase One, running from the Murillo railway crossing along Oliver Road for about 700 metres, included full depth asphalt removal, the removal and replacement of paved curbs and gutters, and the upgrade of catch basins and manholes. Pioneer Construction also laid down additional granular base for cross-fall correction (reducing slope grades), and two 44 mm lifts comprised of new SP 12.5 mm mix. Phase Two of the Oliver Road project encompassed Area 2 (8.1 km of highway between the villages) and Area 3 (last 800 m to Kakabeka Falls).

In Area 2, the company carried out full depth reclamation with expanded asphalt stabilization (EAS) of the existing road to a depth of 110 mm (~54 mm of surfacing and ~56 mm of underlying granular) as the first lift. The roadway was also widened to allow pedestrians on both shoulders. This was topped with a new 50 mm lift of SP 12.5 mm mix. In Area 3, the project team pulverized the existing roadway to make a RAP lift with two SP 12.5 mm lifts of 40 mm depth with tack coat between the layers.

The use of on-site materials for EAS and RAP is an outstanding feature of the Oliver Road project. It reduced material usage and hauling costs for the project while speeding up the repaving.

STEED AND EVANS and CITY OF HAMILTON

Steed and Evans Limited won for the reconstruction of Highway 8 in Hamilton from Park Avenue to the CN Railway Bridge, a challenging project involving a very steep incline and fragile historical properties. The overall $3,719,900 rebuild project, which incorporated the steep rise from Lake Ontario up and over the Niagara Escarpment, included 14,800 square metres of road reconstruction, 990 linear metres of storm sewer replacement, and 1,800 linear metres of curb reconstruction. Each section of Highway 8 was paved with two lifts of binder at 60 mm each and then paved the following day with a 50 mm surface course. 4,165 tonnes of Superpave 19.0 (Traffic Category D) PG 58H-28 asphalt cement was used for the two binder lifts. The surface course was made up of 1,815 tonnes of Superpave 12.5 FC2 (Traffic Category D) PG 58H-28 asphalt cement.

All asphalt paving projects completed between JANUARY 1, 2023 and NOVEMBER 30, 2023 are eligible.

To nominate a project, complete the application form and provide supporting documentation no later than December 29, 2023. Winners will be announced at the 2024 Good Roads conference. For more details, visit goodroads.ca.

2020 Award Winner

Steed and Evans used a number of strategies to address the challenges of the site including using a Material Transport Vehicle (MTV) to feed the paver for all lifts of asphalt which allowed the paver to lay a continuous mat.

They were unable to pave the road in echelon as the contract had originally required as the trucks would have had to back down or up the hill to feed the MTV. And for the part of the project between the CN Rail bridge and Hillcrest Avenue, its trucks had to enter the job site from the south and exit at Brock Road due to the road only being two lanes wide. Loaded asphalt trucks had to cross over the centreline joint to back into the MTV, so the crew had to ensure excellent compaction on the joint.

BRENNAN PAVING and YORK REGION

2021 Award Winner

The winner for 2021 was Brennan Paving & Construction Ltd. for their rebuilding of Kennedy Road/16th Avenue in York Region. Under a $7,574,485 contract, the company removed and replaced over 38.7 lane kilometres of four lane urban arterial roads in a heavy traffic zone that included many vulnerable areas.

The contract covered 3.1 km of four lane roadway with turning lanes on Kennedy Road from Markham’s Main Street to 16th Avenue, and 4.1 km of similar roadway on Kennedy Road from Highway 7 North to 16th Avenue.

The project used 50,368 tonnes of warm mix asphalt (WMA), and consisted of partial depth removal of the existing asphalt followed by the application of WMA. The contract also included upgrades/improvements to five intersections along 16th Avenue and four along Kennedy Road to meet Accessibility for Ontarians with Disabilities Act (AODA) requirements. The quantity of WMA used was 13,578 tonnes of SP 12.5 FC2 Cat D, 22,877 tonnes of SP 19.0 Cat D, and 13,913 tonnes of SP 25.0 Cat D. York Region specified the use of WMA in this project. The region decided to primarily use WMA in 2020 due to its environmental advantages, improved working conditions and handling at lower temperatures, faster re-opening of traffic lanes after paving, and reduced thermal ageing of the asphalt. Using WMA allowed Brennan to manage long shipment times from the plant to the site due to traffic and take advantage of the longer compaction times.

Lara Henry is a communication specialist and editor of ASPHALTopics.

The road forward with

A key to the construction of quality roads is building a solid partnership between road owners and the industry. This year’s Partners in Quality Road Tour presented a unique opportunity for producer members and contractor representatives to get the latest industry information, interact with local municipalities and MTO representatives, and discuss current issues and future plans for the regional area and province.

The Partners in Quality Road Tour (PIQ) was held in April in London, Mississauga, Ottawa, and Sudbury. Recently appointed OAPC Chair, Peter Hamstra, kicked off all four locations as the event MC. He discussed OAPC’s 2023 Strategic Plan with the priorities of Quality; Sustainability; Codes, Standards, and Specification; Research and Education; and Advocacy and Stakeholder Relations. Sustainability is one of the key presentations at this year’s PIQ and a hot topic globally. OAPC’s strategy is to develop a sustainability action plan to meet government’s commitment to net zero by 2050.

The main presentation for the day was “All about Environmental Product Declarations (EPDs) for asphalt mixtures ”. It was presented by Joseph Shacat, Director, Sustainable Pavements, National Asphalt Pavement Association (NAPA), at the London and Mississauga PIQs and by Lianna Miller, Sustainability Manager, WAP Sustainability, at the Ottawa and Sudbury PIQs.

EPDs are documents that specify the environmental impact of a product or material over its lifetime or lifecycle. This presentation was focused up to the point the asphalt mixture leaves the asphalt facility or “Cradle-to-Gate”.

The requirement for EPDs is becoming a norm in the United States as owners are using EPDs to allow them to consider environmental impacts and sustainability when making purchasing decisions. It is no longer only about quality or price. It won’t be long until owners in Ontario and Canada will start to ask for EPDs for asphalt mixtures and asphalt cement and there have already been inquiries to some producer members. Shacat and Miller focused on NAPA’s EPD Program in the U.S. and also showed how a reduction in mix temperatures and aggregate moisture contents, and utilization of RAP, all help in either reducing energy requirements and/ or emissions. Many questions were asked from the audience demonstrating the importance of this topic for the asphalt industry.

MTO`s “ MTO bituminous specification updates and other initiatives ” was presented in London by Imran Bashir, Senior Bituminous Engineer for MTO; in Mississauga and Sudbury by Gelu Vasiliu, Head of Bituminous Section; and in Ottawa by Warren Lee, Senior Bituminous Engineer. Topics included the progression of implementation for warm mix asphalt, a draft NSSP, consultation on the payment adjustment for changes in the PGAC Price Index, and a proposed NSSP BITU0031 Mix Performance Testing (MPT) Specification.

Getting the right information at the right time paves the way for success.

PARTNERS in QUALITY

by Donn Bernal

Representatives from the OAPC-ORBA Municipal Liaison Committee were present to speak about the 2023 Local Municipal Forecast and review the municipal paving survey that they send out to all municipalities annually. Chris Traini, Deputy CAO/County Engineer, County of Middlesex; Amin Mneima, Coordinator, Technical Programs and Research, OGRA/ MEA; Melanie Knowles, Public Works/United Counties of Leeds and Grenville; and Doubra Ambaiowei, Technical Director, OAPC were the presenters.

Local areas also had a presentation on their asphalt initiatives and paving programs and performance updates. Jennie Dann, Director of Construction & Infrastructure Services Environment & Infrastructure, City of London, spoke on their initiatives at the London PIQ, and David Shelsted, Director of Engineering Services, City of Greater Sudbury, updated Sudbury attendees on the city`s initiatives.

To continue the environment and sustainability theme, Doubra Ambaiowei of OAPC and Dr. Kamal Hossain, Associate Professor of Civil and Environmental Engineering, Carleton University, presented “ Quantifying GHG emissions in asphalt plants – A Carleton University & OAPC partnership.” This is a project that Dr. Hossain is leading with assistance from OAPC in gathering and analyzing GHG emissions on asphalt plants.

A PIQ wouldn’t be complete without a CCIL update presentation. Thank you to Nabil Kamil, Manager CCIL Certification Programs, and Emily Worden-Kwok, Assistant CCIL Program Manager.

The final presentation was completed by the OAPC Marketing Committee and highlighted various initiatives including an updated OAPC logo and an upcoming revamp of the OAPC website.

Thank you to all those that participated! PIQ is an important event to continue to maintain the strong relationship between OAPC, its members, the various municipalities and Ministry of Transportation.

OAPC continually tries to find new ways to improve and increase the relationship with all stakeholders. If you have any innovative ideas or have seen something new from other seminars or conference, please feel free to share it with us. To view the presentations, please visit www.onasphalt.org.

Donn Bernal is Principal of Corfinium Solutions Inc.

Practical solutions for planning a road building project

The road-building industry has undergone significant changes due to the recent implementation of regulatory measures addressing excess soil outlined in O. Reg. 406/19. These regulations, a number of which came into effect on January 1, 2023, could have a profound impact on the way construction activities are carried out.

ver the past few months, extensive efforts have been made to collaborate and communicate with various stakeholders involved in the road-building industry. These interactions provided valuable insights and practical considerations that were outlined at the Practical Solutions in Managing Excess Soil course at the 2023 ORBA Road Building Academy. Taking these considerations into account during the planning process could mitigate potential challenges and ensure compliance with the newly imposed regulatory changes.

ROLES AND DEFINITIONS

There are various key roles and definitions for an excess soil project that should be understood before the project commences. One should know the limits and extents of the Project Area, and the Project Leader, Operator, and Qualified Persons (for both the Project Leader and the Operator) should be identified. In the case of most road building projects, the Project Leader is typically the municipality, and the Operator is the road building contractor.

As there could be the potential for a conflict of interest, the Project Leader and Operator may need to hire their own Qualified Persons. Qualified Persons have the expertise and knowledge necessary to assess and address any challenges that may arise during the management of excess soil.

HOW DO THE REGULATIONS APPLY TO THE PROJECT?

One of the initial factors to assess is the potential eligibility for exceptions to specific aspects or the entirety of O. Reg. 406/19. In particular, Section 8 of the regulation primarily focuses on sampling and reporting requirements. However, this section may not be applicable in certain situations, such as when soil removal is required for emergency responses. These emergencies include instances where there is an immediate threat to individuals, the risk of property, plant or animal damage or injury, or when the work is in response to a spill.

Another circumstance that might warrant exceptions is when the infrastructure work aims to maintain an existing infrastructure in a state of repair without any additions or expansions. It is crucial to recognize that there are other scenarios where exceptions may apply, and it is worth considering and discussing the specifics of the aforementioned scenarios during the planning phase of your project.

By carefully examining the potential exceptions provided by the regulation, you can evaluate whether your project qualifies for any of these allowances. This evaluation will inform your decision-making process and help determine the appropriate steps to take to ensure compliance with the regulatory framework while considering the unique circumstances of your road building venture. Engaging in discussions with relevant stakeholders and seeking their input can provide valuable insights and guidance regarding the exceptions that may be applicable to your specific situation.

TENDERING

There may be cases where the Project Leader has already obtained some of the reports mandated by O. Reg. 406/19 in advance or has conducted other environmental assessments that provide valuable information to prospective bidders regarding the nature of excess soil. However, it is important to note that certain tender documents may lack clarity in their language or fail to clearly define responsibilities related to excess soil management.

To navigate such situations effectively, it is advisable to engage the services of a Qualified Person during the bidding process. Their expertise and experience can help ensure that the scheduling and cost implications associated with handling excess soil are thoroughly understood. By involving a Qualified Person, you can avoid unexpected surprises or challenges that may arise later in the project.

Having a clear understanding of the potential issues related to excess soil and incorporating this knowledge into the bidding process will contribute to a more transparent and efficient road building project. Ultimately, the involvement of a Qualified Person will help mitigate risks, ensure compliance with regulatory requirements, and foster a smoother execution of the project.

VOLUME

One of the key considerations in excess soil planning for any project revolves around determining the approximate volume of excess soil that will be generated during the course of the project. The volume of excess soil plays a significant role in shaping the requirements and implications of the project.

EXCESS SOIL REGULATION O. REG. 406

It is crucial to accurately define excess soil and ensure that only actual soil is included in the calculations of the excess soil volume. This ensures that the calculations are precise and reflective of the true amount of soil requiring management. Different volumes of excess soil have varying implications for the project. For instance, if the volume of excess soil is less than 100 cubic metres, it may be permissible to directly transport it to a landfill with minimal sampling. However, this is subject to the approval of the landfill. Moreover, if the soil volume falls below 2,000 cubic metres, there may be exemptions from certain planning requirements as outlined in Section 8 of the regulation. This exemption translates to reduced reporting obligations and less stringent sampling requirements. It is also important to note that the volume of soil to be generated can impact the sampling frequency. Specifically, if the volume exceeds 10,000 cubic metres or 40,000 cubic metres, there are implications on the frequency of sampling that needs to be considered and addressed accordingly.

DESTINATION

When selecting a destination site for excess soil from your project, there are several factors to consider. One of the primary considerations is the proximity of the destination site to your project site. Opting for a destination site that is closer to your project site can result in cost and time efficiencies. Additionally, it is crucial to evaluate the requirements set forth by the receiving sites. Many receiving sites have specific

by

fill management plans that outline the criteria for accepting soil, including quality standards and other relevant factors. Engaging a Qualified Person to review the Fill Management Plan is advisable to ensure that the soil being transported aligns with the receiving site’s requirements. This step helps prevent any discrepancies or issues upon arrival. Furthermore, it is essential to recognize that the receiving site likely has its own Qualified Person who will assess the information and reports regarding the excess soil before its arrival. Providing the necessary documentation and reports ahead of time allows for a smoother process and facilitates compliance with the receiving site’s protocols.

REPORTS AND TIMING

Once the soil volume has been determined and the reporting requirements have been established, it is essential to have a clear understanding of the time required to complete the sampling and reporting processes. If Section 8 of O. Reg. 406/19 applies, and reports such an Assessment of Past Uses, Sampling and Analysis Plan and Soil Characterization Report are necessary, it is typically advisable to initiate the excess soil-related work at least four weeks before on-site excavation activities commence. This precautionary measure helps prevent any potential delays.

Early and transparent discussions with your Qualified Person, once the project has been awarded, are crucial in planning and meeting the excess soil requirements in a timely manner.

Salman Bhutta, Hammad Din and Sina Varamini

In some cases, there may be an option for rush sampling to expedite the process if time efficiency is paramount. However, it is important to note that this can significantly increase costs, with laboratory rates potentially rising up to 100 per cent. Therefore, careful consideration should be given to balancing time efficiency with budget constraints.

By proactively addressing the time requirements for sampling and reporting, collaborating with a Qualified Person, and establishing clear communication channels, you can effectively manage the excess soil-related tasks and maintain a smooth workflow for your road building project.

SAMPLING METHODOLOGY

In the initial stages of construction projects, it is common for excess soil removal to be a crucial step. However, when considering time efficiency, sampling at the start of excavation is generally not the most optimal approach as it results in a delay in the start of excavation activities until the time the environmental sampling, testing and reporting are completed. If done ahead of time, methods such as drilling with a drill rig or test pitting with an excavator are typically necessary for proper sampling. Hand dug test pits are an option for very shallow depths with soft cover which can be broken through with a shovel. These methods allow for the collection of accurate soil samples while ensuring the integrity of the surrounding infrastructure. It is essential to conduct utility locates prior to the commencement of sampling to avoid any potential damage or interference with underground utilities.

By employing drilling or test pitting techniques and completing utility locates before initiating the sampling process, you can ensure a more efficient and systematic approach to excess soil sampling in road construction projects. This consideration helps maintain the overall progress and timeline of the project while complying with the regulatory requirements for soil sampling and analysis.

LEACHATE SAMPLING

The leachate methodology referenced in the Excess Soil Regulation 406/19 is the ministry’s Synthetic Precipitation Leaching Procedure (mSPLP). However, it is important to note that most licensed landfill permits typically refer to the Total Characteristic Leachate Potential (TCLP) which is a more commonly used methodology. If there is a possibility of soil disposal to landfill, it is advisable to also conduct TCLP analyses in addition to mSPLP. This analysis helps confirm whether the soil is non-hazardous and whether the landfill will accept this soil.

TRACKING SYSTEM

It is important to implement a tracking system that documents essential information for each load of soil leaving the project area and being transported to the designated destination site. This tracking system captures important details on each load such as date, time, quantity, and quality of soil. Recently, electronic systems based on smartphone applications or similar technologies have proven to be more robust and efficient in collecting and managing this information. These electronic tracking systems offer advantages in terms of cost-effectiveness and timing. They streamline the data collection process, enhance accuracy, and facilitate seamless communication between stakeholders involved in the soil transportation process.

SOLUTIONS WHEN CONTAMINATION IS FOUND

If unexpected issues arise during the excess soil management process, particularly concerning contamination, there are potential solutions that a Qualified Person can provide. These solutions may include resampling, resampling with averaging, BRAT tool (part of O. Reg. 406/19) and delineation studies. Additionally, exploring alternative approaches like on-site reuse of excess soil can also be considered.

FINAL WORDS

The implementation of O. Reg. 406/19 has brought about significant changes in how excess soil is handled, particularly on construction and road building sites. Understanding the implications of this regulation to your projects is crucial. Engaging Qualified Persons throughout all phases of your projects is highly recommended to ensure compliance and effectively navigate the complexities associated with excess soil management.

Salman Bhutta, Ph.D.,P.Eng. is Principal , Hammad Din, P.Eng. is Manager, Environmental Group, and Sina Varamini, Ph.D., P.Eng. is Director, Pavements and Materials Group, at Engtec Consulting Inc.

Electronic tracking systems streamline the data collection process, enhance accuracy, and facilitate seamless communication between stakeholders involved in the soil transportation process.

UNSUNG HEROES by Steve Pecar

Getting it done in Millhaven all part of the Mark Lewis magic show

lot of companies have a guy like Mark Lewis on their team, but only one company has Mark Lewis. As operations manager for Green Infrastructure Partners (GIP) at the Millhaven Terminal near Kingston, Lewis runs one of the largest asphalt cement terminals in the country — no easy task, but one that he has taken on with both skill and energy as he has helped to lead the business through unprecedented growth and innovation.

“Sometimes I call it the Mark Lewis magic show,” says Steven Manolis, Executive Vice President, GIP Materials Engineering. “The reality is that the high level of execution results from meticulous planning, a profound knowledge of the operation, and time invested into building a high calibre operations team. Mark gets it done because he knows how to do it and has imparted the same can-do attitude in the crack team of employees at the terminal.”

With a background working in chemicals, Lewis started at the company 20 years ago as a technical supervisor when it was still under the Lafarge banner. As Lafarge became Coco Paving in 2008, Lewis transitioned into the role of operations manager where he has overseen all aspects of the terminal. It’s a position he has enjoyed since the beginning, albeit one that has experienced many changes including the most recent when the company became GIP. Lewis has skilfully navigated the operation through periods of expansion to get it to the highcapacity facility that it is today.

“The business is much more complicated today than it was two decades ago,” says Lewis. “With the rise in polymermodified asphalt cement demand, we operate much more of a manufacturing plant than a terminal with very rigorous quality requirements. Our focus is on the customer, to supply the required products on time each and every day. We even added our own fleet of asphalt cement tankers to help us coordinate delivery logistics.”

Mark Lewis

Manolis says that Lewis thrives in his work atmosphere which is both very busy and complicated and presents many challenges. He says his colleague has built an impressive team that “makes it happen” every day.

“There can be a heavy supply schedule in front of him and he has to figure out how to do it and he always does,” Manolis says. “And he always manages to get it done. He’s reliable, and he does it with a positive attitude. He’s a good mentor for the people at the terminal and an all-round respected guy. Everybody at the company and the customers respect him.”

With operations catering to the needs of the customer, Manolis says the “magic” that Lewis performs is done on a regular basis with each challenge presenting unique solutions. “It’s not unusual for a late order to come in, let’s say on a Friday afternoon,” Manolis explains. “And we’re thinking ‘how can we get this done.’ That’s when Mark will think about it then call me back and say ‘if we do this and move that around we can make it work.’ And Mark always makes it work.”

Lewis explains that responding to customer needs is what motivates him and he understands how important it is for GIP to satisfy its customers. He says he and the staff can change directions quickly to make sure the customers get what is needed or have a problem solved. “That’s how we have been successful growing, by helping the customer,” Lewis says.

In the days ahead, Lewis anticipates more challenges which will include spending more time in Mississauga assisting with plant operations there. “GIP is an exciting company. I’m looking forward to the direction we are heading,” Lewis says. “It’s kind of a new era for the company and I am excited to be a part of it.”

Steve Pecar is a Mississauga-based writer, editor and designer.

EXPLORING THE LANDSCAPE OF BINDER FATIGUE TESTING

Not that long ago I was a graduate student in my twenties. Without much difficulty, I could find myself out at night until unreasonable hours and would then complain of tiredness as I dragged myself to the lab the next morning.

That said, some short relaxation with a cup of coffee would always help me bounce back. Since then, I graduated, found a job, got married, got older, lost hair and had my first child – a beautiful baby girl.

That is when I learned the true meaning of fatigue.

A few late nights here and there are manageable, but nightly 2 a.m. (and 3 a.m., and 4 a.m., etc.) wake-up calls, over time, built up quite the accumulation of tiredness. This was fatigue that a coffee break could no longer fix and I often felt as though I’d been run over by a truck.

Speaking of trucks, we are all aware that asphalt pavements also are fatigued over their service life, and fatigue resistance is an essential performance requirement for flexible pavements. In general terms, fatigue damage refers to the degradation of material properties under repeated loading.

by Dr. John Noël

avements experience stresses from each passing vehicle and are strained hundreds or thousands of times each day depending on the traffic volume. They also experience cyclical thermal stresses which can be further exacerbated by freeze-thaw cycles of water. While designing a road to withstand single loads could be straightforward; designing pavements to withstand repeated loads with stresses below the fracture strength is more challenging.

Pavement preparation and structure play a large role in controlling fatigue damage. Weak subgrade can result in larger strains in the pavement above and accelerate fatigue damage. Thick, full-depth pavements are less prone to fatigue damage as they experience smaller strains than thinner pavements under the same loading. Within a given pavement structure and under a certain loading, the fatigue tolerance will be determined by factors including mix design (volumetrics, aggregate properties, etc.) and by the properties of the asphalt binder.

Asphalt binder specifications to control fatigue have long been regarded as a difficult challenge. Many different test methods and specifications have been proposed or implemented to tackle fatigue damage. This article aims to give a brief overview of just a few of these fatigue parameters either in use today or proposed for future use.

Phase angle

Historically, ductility measurements were used as metrics for fatigue tolerance in North America and are still used in some parts of the world today. With the development of the Superpave™ binder specification system, |G*|sin(δ), where |G*| is the magnitude of the complex modulus and δ is the phase angle, was introduced as a fatigue cracking specification with a limit of 5000 kPa. However, there was little field validation conducted for this parameter, and the 5000 kPa limit was set on the basis of correlations to empirical data from the Zaca-Wigmore road trial. This parameter is easy to measure, however and can serve to limit binder stiffness. High stiffness can decrease the strain tolerance of the binder and in thin pavements that experience large strains, can in turn worsen fatigue performance. More recent studies have shown a rather poor correlation between |G*|sin(δ) and binder fatigue resistance.

Closer analysis of the |G*|sin(δ) parameter reveals that it is equivalent to the loss modulus, G’’, the viscous component of the complex modulus. It can then be observed that, in some cases, binders that are less prone to fatigue cracking might be

more likely to fail the specification than binders more prone to fatigue cracking. If one considers two binders with equal values of |G*| but different phase angles, one will find that the binder with a higher phase angle will have a higher value of |G*|sin(δ), making it more likely to exceed the specification limit. Nonetheless, the higher phase angle is indicative of more fluid-like behavior, allowing the binder to better dissipate stresses and prevent the stress accumulation that can lead to cracking. An increase to the |G*|sin(δ) limit in the AASHTO M320 standard was made in 2021 in recognition of this challenge. Now, binders with 5001 < |G*|sin(δ) < 6000 kPa are accepted, provided that their phase angle is greater than 42°, proving they have the viscous behavior required at intermediate temperature to limit cracking.

While the change to the |G*|sin(δ) limit helps prevent highquality, ductile binders from failing the specification, it does not preclude the use of low-phase angle binders that fall below the original 5000 kPa limit, even though these might be more prone to cracking. Recent research has indicated that a lower limit on the phase angle at constant modulus (which can be calculated from the current DSR-PAV test), could be a good specification for screening for binders prone to cracking on their own. A limit of a minimum of 42° has been suggested. Measured at constant modulus, the phase angle is independent of loading time and temperature (no need to select a specification temperature) and correlates well to binder composition (colloidal stability) and to Delta Tc.

Delta Tc

Delta Tc, and correspondingly the m-value from the bending beam rheometer test (AASHTO T 313), can be a good indicator of susceptibility to fatigue cracking, as well. Like the phase angle, the Delta Tc parameter can give an indication as to a binder’s capacity to relax applied stresses and resist cracking, though with poorer reproducibility than the phase angle. In essence, Delta Tc allows binders to be compared based on their capacity to relax stresses at a fixed stiffness (300 MPa). Specifications for Delta Tc are now present in several jurisdictions. ››

Bending Beam Rheometer samples in an aluminum mould.

Time sweep

It has been noted in the literature that traditional DSR testing for fatigue (AASHTO T 315) faces the limitation of applying rather low strains compared to what is observed in real-life pavements, and runs for relatively few cycles, limiting the degree of fatigue that can be observed in the test. The time sweep test was developed during the NCHRP 9-10 research project as an alternate test to measure asphalt binder fatigue properties using the DSR while employing larger strains and many more loading cycles. In the time sweep test, a cyclical shear load of constant magnitude is applied to the binder. Over the course of the test, the complex modulus decreases linearly as the number of cycles increases (damage accumulation), before dropping radically at failure. The point of failure might be taken as the number of cycles at which the curve departs from linearity or the number of cycles at which the magnitude of the complex modulus has been reduced by a given percent. A criticism of the time sweep is that the test duration can be quite long, making it unsuitable for use as a specification.

Linear amplitude sweep

Building from the time sweep test is the linear amplitude sweep (LAS) test. The LAS test, like the time sweep, consists of repeated cyclic shear loads on the binder and is conducted using a DSR. Unlike the time sweep, the shear loading is not constant. In the LAS test, the shear strain amplitude is increased at a constant rate over the course of the test to accelerate failure. Data analysis for LAS test results can be more complex and usually relies on viscoelastic continuum damage models. For the LAS test, there is some variation within the literature as to what the appropriate failure

definition (what constitutes failure) and failure criterion (what value do we take away from the test) should be. Some failure definitions include the point at which: a certain percentage reduction in the complex modulus or loss modulus (AASHTO T 391) is obtained; the shear stress reaches a maximum; the plot of crack growth rate versus crack length reaches a minimum; and others. Some examined failure criteria include the number of cycles to failure, crack length at failure and percent reduction in |G*| or |G*|sin δ at failure.

DSR measurements of stress and strain are made with the assumption that the sample cross-sectional area is constant. However, during the LAS test, edge fracture, delamination, and instability flow can occur, changing the sample dimensions and leading to inaccuracies in the instrument readout. That is not to say that a good relative comparison of binder performance cannot be achieved, but it does make the correlation to other rheological properties difficult. With both the time sweep and LAS there is the added complexity in correctly interpreting a non-linear test and managing the resulting poorer reproducibility.

Glover-Rowe parameter

A more recently developed rheological parameter attained from DSR measurements for assessing binder propensity toward fatigue cracking is the Glover-Rowe parameter (GRP):

Based on the GRP measured at 0.005 rad/s and 15 °C, cracking onset is said to be expected at 180 kPa, with severe damage at 600 kPa and above. The GRP was initially developed as a proxy to traditional ductility tests and does correlate well to binder ductility, as well as to the Double- edge Notched Tension (DENT) test. Like the traditional |G*|sin(δ) parameter, the GRP is heavily influenced by the magnitude of the complex modulus. However, the GRP can have better quality differentiation than |G*|sin(δ) by better screening out binders with the low-phase angle at intermediate temperatures that could be prone to cracking, while more easily allowing higher-phase angle binders with more capacity to dissipate stress to pass.

NCHRP 9-59 now recommends measuring GRP at a higher frequency (10 rad/s) and at an intermediate temperature determined by the low-temperature grade alone and proposes a limit of 5000 kPa, similar to the existing fatigue specification in AASHTO M 320. This measurement can be made using the existing AASHTO T 315 protocol on PAV-aged material and has shown good correlation to binder fatigue strain capacity; however, further validation and examination of limits are likely needed. NCHRP 9-59 also suggests the R-value from the Christensen-Andersen model to be a good predictor of fatigue strain capacity. This value can be calculated from BBR stiffness and m-value but relies on an assumed constant value of the glassy modulus for all binders which might introduce inaccuracies. The R-value calculated in this manner correlates very well to Delta Tc which could be simpler to implement.

Are you feeling fatigued yet? We have touched on at least eight different tests to qualify the fatigue performance of asphalt binders. Others, such as the direct tension test and binder yield energy test, exist too.

This illustrates the breadth of approaches to tackle this challenge: from straightforward like the phase angle at constant modulus to more complex analysis like the LAS to empirical like ductility. While the range of potential fatigue specifications might feel overwhelming, they are proof that the asphalt industry is full of bright scientists and engineers working toward a shared goal: high-performing, fatigue-resistant asphalt pavements.

That is a fact that helps me sleep at night… until the next 2 a.m. wake-up call, of course.

Dr. Noël is Asphalt Technical Advisor for ExxonMobil and is based in Ontario. This article appeared in the fall 2022 issue of Asphalt magazine and is reprinted here with permission from the author and publication.

Dynamic Shear Rheometer (DSR) samples in silicon moulds.

Large Sample Size (25 mm diameter)

Small Sample Size (8 mm diameter)

TECHNICALLY SPEAKING

Doubra C. Ambaiowei Director, Technical Services

Industry hot topics

Attracting and retaining labour in the asphalt paving and roadbuilding industry remains one of the greatest challenges in Ontario currently. In the 2023 OAPC Spring Operations Seminar held in March, participants were quite clear on their thoughts on why the road-building industry is struggling to attract and retain talent. Concerns included wage and compensation issues, long work hours, misconceptions about our industry, competition with other industries, and work-life-balance. Certainly, these narratives need to change.

Thankfully, with support from ORBA, and the specific approaches being tackled by the OAPC Plant and Paving Committee and ORBA’s Education Committee, an implementable strategy is being developed to address the situation. To further drive this process, OAPC intends to zeroin on the subject at our upcoming Fall Asphalt Seminar (FAS) on November 30.

SP103F56 AND CAIS 313-06

If you were not aware, please note that the Ministry of Transportation (MTO) has provided additional updates clarifying the requirements of SP103F56 and CAIS 313-06 on crossfall/cross slope tolerance, exemption applications and contract examples (see ORBA Bulletin #12-23 for details). ORBA was involved with the consultation review processes between December 15, 2021 and January 19, 2022. These efforts were spearheaded by an OAPC Cross Slope Working Group following a call for commentary on Special Provision

313F20, Cross Slope Tolerance Specification on the MTO’s Technical Consultation Portal (TCP). Several issues were raised regarding non-constructability and understanding the impacts to other criteria of lift thickness, compaction and smoothness that need to be met. Please refer to the MTO TCP for those details, including industry comments and MTO responses.

The additional updates to SP103F56 and CAIS 313-06, as we understand it, suggest that the specification’s constructible tolerances and ranges provided are much more forgiving on many projects than we initially thought. In addition, we are reassured of the MTO standards and specifications continuing to evolve and be updated over time as new experiences are gained. To further our collaborative processes, ORBA welcomes continued feedback from members on these specifications and special provisions through implementation on projects.

ORBA is also mindful of the challenge to many contractors who don’t have historic data to understand how they performed in the past, and the difficulty evaluating the impact of the new specification changes. As a result, we are expecting to further industry’s understanding of the cross-slope specification changes and its implications via a webinar that is expected to discuss the clarifications to SP103F56 and CAIS 313-06 including updates based on trial and/or demonstration contract experiences implementing the new specification. This webinar, scheduled for September 13, 2023, is an opportunity for members ››

to ask those very tough questions they have on their minds –please stay tuned for updates and more on ORBA’s webinar series.

CRM AND RAP

An additional item on the radar, or perhaps a re-emerging focus pertaining to asphalt optimization, is about Crumb Rubber Modified (CRM) asphalt and the opportunities with Reclaimed Asphalt Pavement (RAP). I might be somewhat biased per my own experiences, but without doubt there can be a future for rubberized asphalt in Ontario. As I mentioned in a recent interview with the Asphalt Institute, this subject of optimizing the benefits of CRM and RAP was the focus of my doctoral thesis at the University of Waterloo between 2011 through 2014.

In a bid to better understand and resolve the technical challenges associated with recycled hot mix asphalt (HMA) mixtures as well as to advance Ontario’s paving industry to a more sustainable and economically viable direction, my scientific investigations involved a comprehensive laboratory testing program to characterize the behaviour and mechanistic properties and compare the overall performance of an array of typical Ontario Superpave HMA mixtures incorporating 0, 15, 20 and 40 per cent RAP,

and CRM mixtures with 20 per cent RAP. The laboratory testing protocols selected to characterize these mixtures included:

- Binder rheological assessment tests to assess failure properties and grade asphalt binders;

- Thermal Stress Restraint Specimen Test (TSRST) to determine fracture susceptibility at low temperatures;

- The Hamburg Wheel Tracking Device (HWTD) for assessing the combined effects of rutting, stripping potential and moisture susceptibility;

- Dynamic Modulus tests to evaluate the viscoelastic properties of the experimental matrixes over a range of loading frequencies and temperature scenarios; and

- A forensic assessment of past CRM pavement sections, field monitoring of CRM-RAP demonstration sections, and an overall cost and sustainability assessment.

The rheological characterization of binders indicated that the influence of RAP variation was highly related to the performance grade of the base virgin asphalt cement, while CRM binder modification significantly improved both complex shear modulus (G*) and phase angle (δ) parameters regardless of the binder grade. This had a significant impact on the rutting and thermal cracking performance of the evaluated HMA mixtures. With exceptions to the recovered binders from 20 per cent and 40 per cent RAP HMA mixtures with PG 52-40 and 52-34 binders, all other recovered binders were observed to be more flexible at low and intermediate temperatures, suggesting that the potential for improved resistance to fatigue failure exists. An assessment of the dynamic modulus (|E*|) and phase angle (δ) data suggested that the observed mix stiffness was not exclusively a function of the improvements made by the improved characteristics of the binder, but in combination with other factors. The master curve construction using the rheological analysis software (RHEATM) confirmed these behavioural tendencies. The observed mix stiffness was further observed to correlate well with the mechanistic performance test results.

Overall, the wet-process rubber terminal-blend HMA mixture was noted to be distinctively different from the rubber fieldblend mixtures in terms of performance, but no evidence within the confines of the investigation suggested that the rubber field-blend method was not effective or feasible. In-service pavement monitoring at the time indicated that the rubberized-RAP sections were all performing very well in comparison to the control sections with RAP.

The study findings further demonstrated the potential to incorporate up to 40 per cent RAP contents into rubberized pavements. The 40 per cent RAP HMA mix was found to be the most environmentally friendly pavement design alternative. However, the 20:20 per cent CRM-RAP HMA mix was judged the most innovative and optimal sustainable option having satisfied the functional performance criteria and being the most cost-effective.

Based on these findings, the investigations recommended that CRM used in Ontario rubberized HMA mixtures should be subjected to both cryogenic and ambient methods of grinding. This was considered a more effective way to ensure better or comparable performance with conventional HMA mixtures. The higher initial construction costs would be offset by the many benefits associated with rubberized pavements including prolonged service life over the pavement’s lifecycle especially in terms of maintenance or the need to carry out major rehabilitation.

Therefore, in my opinion, it can be considered reasonable and practical to conclude that RAP and CRM are valuable components of optimizing HMA mixtures in Ontario. Many might argue that the derivable benefits are subject to jurisdictional applications, which is fair, but ultimately it comes down to how the materials are engineered to perform, and perhaps available production and placement expertise. This CRM-RAP combination is innovative and supportive of any green and sustainable pavement objective, but is Ontario ready to re-engage?

In the general road-building focus, another re-emerging focus is connected to the short and long-term benefits of using calcium chloride in road base stabilization applications. These benefits comprise moisture and density control during construction, enhanced lubricity and compaction of granular material, and better overall freeze thaw performance. In one of my past study involvements, an evaluation of the in-situ resilient modulus was completed using a Falling Weight Deflectometer (FWD) at four different points during construction and the early performance period.

While it was theorized that the calcium chloride stabilization process would increase in-situ density resulting in higher early resilient modulus values than the unstabilized control sections, this case was not observed and was likely because there was no improvement in density in the stabilized sections at the time of construction. The testing results indicated an observable strength gain between the time of construction and the first spring. The gain in resilient modulus was approximately 20 per cent which was similar to previous reports which noted a 30 per cent strength gain.

I would be pleased to hear from you as regards the pros and cons of a CRM-RAP combination for Ontario roadway applications, and the opportunities with calcium chloride in road base stabilization applications. Please connect with me at: Doubra.Ambaiowei@orba.org

Lastly, if you did not know, please be advised that AASHTO T 164-22 has replaced AASHTO T 164-14 (2018), “Standard Method of Test for Quantitative Extraction of Asphalt Binder from Asphalt Mixtures” (ASTM Designation: D2172/D2172M-11). Also, ASTM has finally published a standard for aramid used in asphalt paving mixes - ASTM D8395-23 “Standard Specification for Aramid Fiber for Asphalt Mixtures”. A process to get aramid fiber recognized in the OPS is in the works. The Good Roads/OAPC Municipal HMA Liaison Committee, and OAPC-HMA Technical Working Group are in consultation with the OPS Pavement Committee to provide recommendations for revisions to OPSS MUNI 1101 and 310.

ENVIRONMENTAL ESSENTIALS

Doubra C. Ambaiowei Director, Technical Services

Quantifying greenhouse gas emissions in asphalt plants

In 2020, the transportation sector was responsible for approximately 25 per cent of Canada’s total greenhouse gas (GHG) emissions with 159 megatonnes of carbon dioxide equivalent. Between 1990 and 2020, GHG emissions from the transportation sector grew by 32 per cent. Under the Paris Agreement, Canada has committed to reducing its GHG emissions by 30 per cent below 2005 levels by 2030, and Canada is dedicated to carrying out its expanded climate plan to reach net zero emissions by 2050.

With the above-mentioned facts in mind, one of the strategic priorities of OAPC is focused on sustainability aimed at promoting asphalt strategies, initiatives and processes that will benefit the environment, improve society, and provide an overall economic benefit.

In pursuit of these objectives, the OAPC Environment Subcommittee is mandated to develop an action plan to meet government’s commitment to net zero by 2050. There is no doubt this is an important focus for the transportation sector, but the road-building industry and specifically the asphalt paving industry must take this very seriously if it intends to stay competitive with other markets.

To meet these environmentally-focused demands, OAPC aims to partner with Carleton University’s Advanced Road & Transportation Engineering Lab (ARTEL) and the National Research Council (NRC) in a Natural Sciences and Engineering

Research Council of Canada (NSERC)-sponsored study aimed at quantifying greenhouse gas emissions from asphalt plants. The council’s interests and expectations from this study include:

- Quantifying the GHG emissions, the energy sources, and their corresponding emissions from different types of asphalt plants;

- Preparing a recommendation for sustainable asphalt mixing technologies and processes considering environmental conservation and the economy; and

- Integrating the findings of the study into MTO’s GreenPave Rating System.

Our focus on quantifying GHG emissions in asphalt plants is to ensure that we can move the needle further toward targeting the best ways to minimize such emissions while achieving the maximum mix production rates. Within the cradle-togate framework, the important focus in asphalt production comprises of raw material extraction, transportation, and production stages.

Material extraction is the stage where natural resources such as aggregates (gravel, sand, crushed stone), asphalt cement, and raw materials for Portland cement are extracted from their natural sources, including quarries, mines, and natural deposits. This stage involves the extraction of materials that will be used in the pavement construction process, including aggregates and binder materials. The environmental impact

of the extraction process must be considered, including potential disturbance to ecosystems and habitats, soil erosion, and dust and noise pollution.

The transport stage involves moving the extracted materials and other materials such as equipment, fuel, and personnel to the construction and/or production site. This stage requires transportation infrastructure such as roads, railways, and waterways, as well as vehicles and vessels. The distance and route of transportation contribute significantly to environmental impacts, including fuel consumption, emissions, and traffic congestion.

The production stage involves the manufacturing of pavement materials such as asphalt and concrete, etc. The materials are produced at specialized facilities using a mix of raw materials, additives, and energy sources. Energy consumption and emissions are prominent during the production stage which must be minimized using efficient production methods, alternative energy sources, and emission control technologies.

Asphalt is an environmentally friendly and sustainable option, and this is corroborated by the potential for emission reduction in strategies comprising of the use of recycled materials, use of natural gas as burner fuel, aggregate moisture content reduction, use of warm mix asphalt (WMA) technologies, reduction in electricity consumption intensity, and an overall fuel consumption reduction in the production processes

If we are successful with the stated objectives of this NSERCCarleton University partnership, the gains could be further translated into the MTO GreenPave Rating System. GreenPave incentivizes the reduction of GHG emissions from asphalt production, encouraging asphalt producers to achieve higher ratings and reduce their environmental impact, and these are achievable within the specific rating areas of “ Materials & Resources, and Energy & Atmosphere.” In the current GreenPave guidelines, the energy used to produce concrete

is substantially lower than asphalt due to liquid bitumen assumed to be a form of energy itself known as feedstock energy. Consequently, the asphalt industry is tasked to provide more support and project level GHG/energy savings We also need to investigate new technologies in hot mix asphalt, and how it will impact the GreenPave rating.

Quantifying GHG emissions in asphalt plants is a crucial step towards understanding the impact of asphalt production on the environment and sustainability. This study will explore the activity inventory and emission factor approaches which are commonly used methods for estimating GHG emissions associated with asphalt production. Depending on findings, it will be possible to recommend changes to the existing emission factors that are usually obtained from Environment and Climate Change Canada’s National Inventory Report, and specific to each province. The use of sustainable practices such as warm mix asphalt and reclaimed asphalt pavement can significantly reduce GHG emissions. Reducing GHG emissions in the asphalt industry can lead to direct benefits such as cost savings, increased efficiency, improved public perception, and meeting regulatory requirements.

It is said that in poor weather conditions, a good pilot will always trust his instruments to navigate. Drawing from that analogy, the asphalt industry will need to trust the data it generates to improve its outlook in conversations involving the environment, production, performance, and economics. The quality of the data we can generate is dependent on the sort of production input and sources we are able to evaluate through the expected 3-year study duration. The output will enhance the industry’s competitiveness and access to government funding and incentives.

OAPC will come calling for participation from Ontario’s asphalt producers when this NSERC partnership study eventually takes flight – please stay tuned!

BREAKFAST SPONSORS

Thank you

to our sponsors of the Spring Operations Seminar –March 23, 2023

2023 OAPC AWARDS NOMINATIONS DEADLINES

Do you know someone who stands out in the industry? Nominate them for an OAPC award today.

Nomination submission due OCTOBER 27, 2023:

• The “Bleeds Black” Award

• Dr. Norman McLeod Award for Innovation

Nomination submission due NOVEMBER 30, 2023:

• Joe Bunting Mentorship Award

• King Beamish Excellence Award

• Earl Kee Volunteer Award

• Honorary Life Membership Award

INDIVIDUAL SESSION SPONSOR

5th ANNUAL ASPHALT TECHNICAL SYMPOSIUM

OAPC’s fifth annual Asphalt Technical Symposium held on June 13, 2023, was a fantastic success! In collaboration with MTO and industry partners, we had a day filled with engaging conversations on asphalt binder challenges, mix performance testing, and some eye-opening findings from the Ontario-Mix Asphalt Program (O-MAP) Round 2 study. Add in an exclusive tour of MTO’s impressive new lab and it was a day to remember. A big thank you to everyone who joined us and made it such a valuable and insightful event! Click here to access presentations from the event.

THANK YOU TO OUR 2023 SPONSORS

HAVE YOUR SAY ON THE FUTURE OF OAPC’S TRILLIUM AWARD PROGRAM

OAPC is running a survey to gather feedback on how we can further enhance the Trillium Award Program for our members and the communities they serve. So don’t be shy – share your thoughts and ideas with us through the survey. Take the survey here.

2023 Trillium Program applications are now open. Learn more and apply.

Thank you

to our sponsors of the Partners in Quality Road Tour – April 4 to 13, 2023

GOOD ROADS CONFERENCE

Doubra Ambaiowei, Technical Services Director, represented ORBA/OAPC at the Good Roads conference in Toronto on April 18. With more than 1,500 attendees, the annual conference featured over 80 sessions, a variety of speakers, study tours and a sold-out exhibitor hall.

ORBA WEBINARS

• NRC’S PLATFORM TO DE-CARBONIZE THE CONSTRUCTION INDUSTRY

July 19, 2023

• CURRENT AND FUTURE APPLICATIONS OF 3D MILLING TECHNOLOGY

July 26, 2023

• STAYING UP-TO-DATE ON CROSSFALL/ CROSS SLOPE TOLERANCE WITH MTO

September 13, 2023

For more information, visit https://orba.org/webinars/ Make sure you don’t miss any details and subscribe to our email list!

OAPC

NOVEMBER 30

ORBA CONVENTION

FEBRUARY 4 to 6, 2024 Scan

THE LAST WORD

Bridget Mills

The Last Word

Having just retired from over 30 years in environmental consulting primarily serving Ontario’s aggregate, and, in particular, asphalt industry, this is indeed my “last word” (no sighs of relief please!). I thought it would, therefore, be most appropriate to take this opportunity to highlight a few of the industry’s many environmental accomplishments over the last three decades.

One of the key achievements has been in environmental permitting. Almost 100 per cent of Ontario’s asphalt plants have their up-to-date environmental compliance approvals (air and noise). This is no mean feat. Over the years, the scope of approvals has changed enormously from permitting a single piece of equipment (remember those one page approvals with no conditions) to the entire site; from assessing just a few air contaminants to many contaminants; from using a simple air dispersion model to a complex model (AERMOD and no, it doesn’t help to look up the acronym!); from a single set of half hour standards to multiple time averaged standards; and lastly, to the introduction of alternative permitting regimes for certain contaminants. For the latter, the development of the Asphalt Mix Industry Standard was a very significant achievement in itself. It highlighted OAPC’s foresight into future legislation potentially impacting its members. It also showcased the unique co-operation and dedication of OAPC’s producers and suppliers (seven long and patient years).

Another key achievement is how the industry has and continues to manage encroachment. Historically, asphalt plants and AC terminals were generally situated far from residential areas. For many facilities, this is no longer the case due to new residential development around existing plants. The industry, however, has responded admirably to this challenge. From preparing fact sheets to educate the facilities and their neighbours; to meeting openly with ministry representatives and neighbours at their facilities; to commissioning studies to investigate concerns; to modifying asphalt mixes; and to implementing physical and operating controls both retroactively and proactively, industry has taken a responsible approach.

Finally, in my last few years I have seen how the asphalt industry is actively responding to climate change and sustainability from creating a dedicated environmental sub-committee; to calculating carbon footprints; to developing Environmental Product Declarations; to updating best practices; and even to including specific articles in ASPHALTopics and forward thinking seminars in their conferences.

As new roads (literally and figuratively) open up for me in my retirement, I am proud to have been an active OAPC director and I am confident that the industry will continue to be innovative, dedicated and the very best that it can be.

Bridget Mills was president of BCX Environmental Consulting.