Concrete Contractor February/March 2021

How to Repair Cracks in Stamped Concrete

28 February/March 2021

THE LEADING TRADE MAGAZINE IN THE CONCRETE INDUSTRY

Lakeside

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When a $35K project grows to $160,000

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GREEN CONCRETE

TAKES A LEAP FORWARD

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WHAT’S INSIDE

FEBRUARY/MARCH 2021 | Issue 2, Volume 21

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COVER STORY 14 The Latest in Lighter Concrete The accidental discovery of reducing the weight of a precast concrete while keeping the strength at the same time.

DEPARTMENTS 6

Editor’s Letter

8

New Products

C p

S

26 Product Focus Concrete Repair Products

44 Advertiser Index 45 The Last Placement

A

Cover Photo Credit:Green Global Concrete Technologies

FEATURES 10 The Impact of

28 Repairing Stamped Concrete Fixing some of the common problems and a few techniques you can try the next time you are faced with a challenge.

Admixtures on Sustainability

Two examples that illustrate how admixtures can be used to reduce the CO2 footprint of concrete.

32 Lakeside Magic Alchemy Concrete’s under 5,000 sq.-ft. award-winning work.

18 How to Evaluate &

Troubleshoot Concrete Cracks

They’re either the total extent of damage or the first signs of serious trouble. Here are some recommendations for troubleshooting cracks prior to designing or performing repairs.

24 Concrete Repair

Training & Online Certification

Build up skilled employees with continued education and online training options.

38 Specification Guide: Power Trowels Technical data to help you choose your next power trowel.

40 World of Concrete Idea Files

WHAT’S ONLINE Enhance Grading Efficiency & Cut Costs by 10% Listen to this podcast on TraceAir’s construction site development platform ForConstructionPros.com/21271005

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FEBRUARY/MARCH 2021

34 The First Step in Choosing the Right Abrasive In surface preparation, there are a number of things to consider when selecting a metal-bond diamond abrasive. First, start at the concrete floor and figure out what you’re working on.

7 Ways Construction Can Leverage the Power of Big Data Mining large data repositories and the game-changing benefits from keeping all project decision makers on the same page.

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BUILDING TRUST ON EVERY JOB.™ 2/15/21 12:14 PM

EDITOR’S LETTER

Is it Polite Behavior, or Just Good Business?

I

spoke with Judah Haas of Alchemy Concrete for this issue to talk about their award winning decorative concrete work. If you haven’t already, flip ahead. The work done is a great example of a lakeside home set in the woods of the north half of the Midwest (in this case Wisconsin). What stood out to me JONATHAN KOZLOWSKI, while speaking with the team was their ability to not EDITOR only adapt to the unforeseen issues that came up, but JKOZLOWSKI@ ACBUSINESSMEDIA.COM their willingness to work with the client and graduate what would have been a standard job to a custom work of (dare I say) art. I don’t want to tell the entire story here, but I will say that it seemed like it was one of those projects that the client kept adding.

One of the owners even joined the contractor in the office to get hands-on in the creation of a table they designed.

I’m sure you’ve experienced something like this once or twice and I bet these requests often sounded almost impossible to do. Handling these situations with professionalism, compassion (and passion), as well as a handful of patience and understanding can help projects to grow and can be an important part of keeping your client happy. Although some good communication and educating the customer on what is and is not possible can go a long way too. It’s this sense of accommodation and willingness to adapt to the evolving project that allowed the award-winning work to be exactly that.

While the team at Alchemy went above and beyond, I have to believe that any contractor out there would do the same. Of the few contractors I’ve spoken with so far in my few months with Concrete Contractor each and every conversation left me with the feeling that they valued good work done well and that includes working with the customer. In an article from 2007, Linda Hanson writes about how happy customers come back and discusses the value of good customer service. Two of the six suggestions include making customer service a focus from the top down and to know your customer. (You can find Hanson’s piece at ForConstructionPros.com/10297917.)

Judging by the project by Alchemy Concrete Inc. as an example of what can be done by good communication with the customer, Hanson’s advice still rings true. In the end, is it just being polite, or it is good business?

Pretty sure it’s both.

Stay safe out there.

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Advisory Board

James Baty II Concrete Foundations Association Mt. Vernon, Iowa

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Jim Cuviello Cuviello Concrete Polished|Stained|Crafted Stevensville, Md.

Kim Basham KB Engineering Cheyenne, Wyo.

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Chris Klemaske T.B. Penick & Sons, Inc. San Diego, Calif.

FEBRUARY/MARCH 2021

Dennis Purinton Purinton Builders, Inc. East Granby, Conn.

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NEW PRODUCTS

7

PRODUCTS FOR THE CONCRETE INDUSTRY

J-CAP Safety Cover

The EXO-O1 wearable exoskeleton from Hilti North America will help commercial contractors, tradesman and management alike, tackle repetitive-stress health and safety as well as labor-shortage challenges. Wearable human augmentation devices such as exoskeletons will reduce strain and fatigue for both experienced and novice users, making the most of the available workforce at a time when the industry is struggling to fill open construction positions. The exoskeleton development is initially focused on shoulder-height and above applications because this type of motion is so physically intensive and fatiguing.

To create the EXO-O1, Hilti Group partnered with Ottobock, provider of prosthetics, orthotics and exoskeletons that help people increase and retain their physical independence.

The J-CAP Safety Cover is made of strong glass reinforced recyclable polyethylene material. The universally-designed product covers most column base brackets and post bases, along with metal flat nail forming stakes. The product covers most column and post bases along with metal forming stakes. The J-CAP OSHA Approved Safety Cover protects against lacerations while taking away the risk of impalement from at grade level falls up to 10 ft. (3.04 m). It also protects employers from any OSHA fines related to column base brackets or metal forming stakes.

• Above-grade OSHA approved • UV Protection • Brightly colored for easy visibility • Simpson Strong Tie and Mitek covers most post brackets • Fits all 3/8-in. metal flat nail concrete forming stakes

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The Hilti EXO-01 Wearable Exoskeleton

Ameripolish SmartFloor Pad System

The SmartFloor concept is engineered to provide the end user with a highly aesthetic floor and an easy and economical way to maintain a polished concrete floor utilizing standard janitorial equipment and existing personnel.

• Easy-to-use pad system, Daily Maintenance (blue) and Restoration (orange) • Designed for use under auto-scrubbers and floor machines • Innovative and patented composite resin abrasive technology • Sizes 13, 14, 15, 16, 17, 20 and 24 in.

PoreShield Bridge Sealant

PoreShield is ideal for bridge construction, major highway projects and other large-scale roadway infrastructure applications. Unlike any other existing method, it protects concrete from the inside out with a flexible, hydrophobic barrier that is absorbed deep into the pores.

With preventive and self-healing properties, this barrier stops any existing damage and deterioration from getting worse. This barrier makes PoreShield the most durable solution available to protect concrete against water, salt and freeze/thaw damage. In fact, it is proven to significantly reduce diffusion of chloride ions, which are commonly found in deicers, the number one culprit of concrete damage.

PoreShield is derived from soybeans, it is low in VOC and reduces application time. PoreShield requires no personal protective equipment and eliminates the need for hazardous waste cleanup.

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Euclid Chemical's Solvent-free Dural 50 LM FS Solvent-Free Epoxy Coating

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The reusable Form-A-Tube allows contractors to instantly construct forms for shoring up pilings with cement. The system builds forms of any size on site, making it easy to use even in remote locations.

“This stuff is so modular you can take it down into 6 1/2-in. strips, and put it together on site,” says Harvey Sharp, whose company BCG Services is handling a water pumping station in Houma, He found Form-A-Tube to be effective, economical, and fast.

To combat water-related damage and ensure optimal concrete protection and repair, The Euclid Chemical Company adds the Dural 50 LM FS Coating to its line of epoxy-based products.

Dural 50 LM FS is a low-modulus, solvent-free, fastcuring epoxy sealer designed to penetrate concrete and protect it from the damaging effects of chlorides and water. It is designed to repair and seal cracks in concrete substrates, while also significantly reducing chloride intrusion. Its ultra-low viscosity ensures superior substrate wetting and easy penetration into static cracks of concrete surfaces.

It can also be used as a fast-setting primer for epoxy polymer overlay systems.

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FLATWORK/SLABS

»

BY DIEGO GRANELL

The Impact of Admixtures on

SUSTAINA

Adobe Stock Images | By Nuttapon

10 CONCRETE CONTRACTOR

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FEBRUARY/MARCH 2021

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NABILITY Two examples that illustrate how admixtures can be used to reduce the CO2 footprint of concrete.

C

oncrete admixtures can be used to reduce cement content, permit greater use of supplementary cementitious materials (SCMs), and even increase resistance to the environment to extend the lifespan of structures. Admixtures also have the potential to affect a reduction in the CO2 emissions associated with concrete production. However, the impact of admixtures on sustainability can be complex and involve many variables.

EXAMPLE #1

SUPERPLASTICIZERS Superplasticizers can be used to reduce water in a mix which allows for a reduction in cement content while maintaining the same w/c ratio and equivalent strengths. For example, a reference concrete with 350 kg/m3 (590 lbs./yd.3) of cement and 200 kg/m3 (337 lbs./yd.3) of water (0.57 w/c ratio) proportioned to produce a 150-mm slump (5 in.) can be treated with a superplasticizer. Using a moderate dosage of superplasticizer the water content of the concrete can be reduced

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FLATWORK/SLABS CONTINUED

yd.3) of cement and 20 kg/m3 (34 lbs./yd.3) of water. Some sand can be added to the mix to maintain an equivalent yield.

The sum of these changes results in concrete with about a 9% reduction in CO2 emissions. It is clear that higher sustainability can be achieved with higher water reduction, and that there is room for improvement in this direction.

EXAMPLE #2 GCP Applied Technologies

to 180 kg/m3 (303 lbs./yd.3) and the cement content can then be reduced to 316 kg/m3 (533 lbs./yd.3) while maintaining slump, w/c ratio, and strength.

The use of the superplasticizer allowed us to remove 34 kg/m3 (57 lbs./

12 CONCRETE CONTRACTOR

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FEBRUARY/MARCH 2021

SUPERPLASTICIZERS & ACCELERATORS IN SCM MIXES In this example, we will follow similar methods as in Example 1 to illustrate how the combined use of superplasticizers and set accelerators can enable more aggressive 50% cement replacements in a concrete mix.

Starting with a mix that has 356 kg/ m3 (600 lbs./yd.3) of cement and 180 kg/m3 (303 lbs./yd.3) of water, (0.51 w/c ratio), proportioned to produce a 150 mm (6 in.) slump.

Using a similar dose of superplasticizer to Example 1, we reduce the water content of the mix to 160 kg/m3 (270 lbs./yd.3) and the cement content to 178 kg/m3 (300 lbs./yd.3). The cement removed is replaced with 178 kg/m3 (300 lbs./ yd.3) of fly ash, resulting in a water-tocementitious ratio of 0.45.

We are going to use the lower w/c and a set accelerator to overcome the extended set times and the lower early strengths associated with this high cement replacement level. The dosage of the set accelerator will depend on the ambient conditions at the time of placement. Later-age strength is typically not an issue for fly ash mixes.

The sum of these changes results in concrete with a very significant 43% reduction in CO2 emissions.

If allowance for slower strength development were possible, thus

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“Creative use of concrete admixtures, alone or in combinations, can be used to make significant reductions in CO2 emissions associated with concrete production.”

AdobeStock/Aisyaqilumar

allowing less accelerator use, the CO2 emissions would be further reduced.

While these examples are similar to mixtures that have been used in construction, testing with local materials must be conducted to determine the dosages of admixtures and the final performance of the concrete.

Creative use of concrete admixtures, alone or in combinations, can be used to make significant reductions in CO2 emissions associated with concrete production.

Editor's note: Environmental assessment comparisons of the concrete were used to determine the CO2 emission reduction.

Diego Granell is a Director of Product Management and Marketing at GCP Applied Technologies in Cambridge, MA. He is globally responsible for the development and introduction of new cement additive and concrete admixture products and systems with a strategic research focus on technologies reducing embodied carbon in concrete mix designs.

Diego received an M.S and B.S. in Civil Engineering from the Technical University of Valencia, and an MBA from Dartmouth College’s Tuck School of Business.

For more on sustainabilty, visit ForConstructionPros.com/ sustainability.

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COVER STORY

»

BY JONATHAN KOZLOWSKI

GREEN CONCRETE

TAKES A LEAP FORWARD

The accidental discovery of reducing the weight of a precast concrete while keeping the strength.

I

t’s a simple concept with a not so simple answer: reduce the weight of concrete without compromising strength. Let’s complicate things one more factor and address environmental issues as well; not just a reduction of carbon in the production process but the trash you put out at the curb.

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FEBRUARY/MARCH 2021

This story begins as many discoveries do—as an accident in someone’s garage.

“This is all an accident,” says Bart Rockett, owner of Philadelphia Polished Concrete and Rockett’s Glass Overlay.

He was originally attempting to further develop his polished concrete overlay system, a flooring which utilizes 100% recycled post-consumer glass chips to create a terrazzo effect. It’s reported to be 30% cheaper along with a 20-year long warranty. The system was designed to be highly polished and at $8 less per foot than traditional terrazzo, had the potential to save the polishing contractor a

Compared to a panel of concrete with steel rebar the same size, Space Age Concrete will reportedly be 50% lighter using fiberglass reinforced rebar.

Green Global Concrete Technologies

substantial amount of money while producing a high-quality floor.

Rockett started his concrete experience with 25 years of architectural concrete prior to polishing, the “green” recycled glass aspect drew him to the polished concrete industry and then a glass overlay. After these decades of

www.ForConstructionPros.com/Concrete

2/15/21 12:54 PM

experience, numerous awards on his polished concrete work (in 2016 he won the “Reader’s Choice Award” at the World of Concrete and 22 other awards throughout the years—so far), he had his sights on retiring. So much for welllaid plans.

While stopping for gas, Archie Filshill saw Rockett’s truck and that he was working with recycled glass. As far as Filshill knew, he was the only one doing anything with the material.

Filshill is the CEO and co-founder of AeroAggregates, a manufacturer of ultra-lightweight closed cell foamed glass aggregates (FGA). The company’s kilns also use 100% post-consumer recycled glass much like Rockett’s Glass Overlay flooring but to produce a building aggregate that is lightweight, noncombustible, insulating, free-draining, non-absorbent and resistant to chemicals, rot and acid. This makes FGA a great alternative option for construction, lightweight embankments, load distribution platforms and insulating subgrade, as well as lateral load reduction behind retaining walls and structures.

In October 2020, “He approached me and wanted to know what I was doing,” says Rockett. “He says, ‘If you could get these rocks [his aggregate] in concrete you’ll have something special.’”

AeroAggregates have been available in Europe for roughly 30 years, and eight here in the U.S. Marrying the lightweight qualities of a glass-based foam aggregate with cement, according to Rockett, has been a problem without a solution.

Meanwhile, Rockett was already utilizing a white csa cement in his flooring to ensure he gets the aesthetic and performance quality he wants in his flooring. Curious to see what would happen, he mixed this cement and the lightweight aggregate. “Once I put the cement in there, [the aggregate] floated right to the top,” says Rockett. Not exactly the effect you want to happen if one was trying to mix a batch of concrete. Never the less, his curiosity urged him to continue.

GGCT is setting up at the AeroAggregate’s Complex in Eddy stone, Penn.

Green Global Concrete Technologies

White csa cement was originated by a company named Caltra, located in The Netherlands. One of the distributors Rockett uses is Delta Performance, who specialized in admixtures, coloring, and cement special effects. While typical concrete are gray, explains Shawn Hays, owner and president of Delta Performance, the white quality in the cement allows contractors to color it virtually any color—a unique ability that would lend itself to creative design in the special applications when color is of importance.

“I look forward to working with Joe Ginsberg [a well-known designer out of New York also working with Rockett] to coming up with some things that are pretty darn unique,” says Hays.

Another benefit of utilizing a csa is to take advantage of an already reduced carbon footprint. “Basically, csa cement is a rapid setting type cement and an alternative to Portland cement,” says Hays. “The csa cement in the manufacturing process is similar to Portland, but it’s actually fired at a lower temperature so it’s considered to be—or marketed to be a greener cement.”

The kilm for the AeroAggregate glass rock Green Global Concrete Technologies

www.ForConstructionPros.com/Concrete

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IGNITION Through a now patented process, he and a small network of industry experts prototyped a block where the fibers created a gabion effect to hold the aggregate in suspension within the concrete—not floating to the top. “This is the holy grail that all of us in the industry have been trying to find for 30 years,” he says.

Dubbed Space Age Concrete, it is being made into precast products.

Strengthened by a glass-reinforced rebar which is greatly lighter than its steel counterpart (not to mention reportedly five times stronger), the concrete panel is reportedly 50% lighter than traditional concrete and impressive strength data.

“When we were all done mixing our special cocktail, we were at 90 lbs. per cubic ft. vs 150 of regular concrete,” explains Rockett. “Not only does the concrete weigh less, but now your whole structure is going to weigh astronomically less. We weren’t trying to develop this. It was just luck on a Saturday night sitting in my garage. I had some extra cement and didn’t want to waste it. That’s how it all began.

If I didn’t get involved with polished concrete 12 years ago, it would have never evolved into the flooring system which would have never evolved the lightweight cement.”

A month later Green Global Concrete Technology Company (GGCT) was formed, a partnership which included several particular partners who saw the potential of Rockett’s new precast product.

FEBRUARY/MARCH 2021

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COVER STORY CONTINUED TAKE OFF He’s created two different versions of Space Age Concrete: an infrastructure mix in standard concrete gray and an architectural mix in white for coloring and design. Plans on “proof of concept” projects are already on the horizon.

Initial work includes building of a three-story demo structure featuring a basement and rooftop, pedestrian footbridges, sound barrier walls, homeless homes/shelters, culverts and more.

Heading GGCT’s design is Joe Ginsberg. Recognized as #39 by Inspriation magazine’s Top 100 Designers in the world and Covet House magazine’s Best 25 Interior Designers in New York, Ginsberg connected with Rockett for his glass overlay flooring while restoring a lobby.

At current, the plan is to have all future project designs to have Ginsberg’s eye at their core. At least initially, he and the team plan to oversee and lead on projects featuring the precast Space Age Concrete product to ensure installation is done correct and to a standard.

Work in using Space Age Concrete has already begun. Looking to break ground by August, Ginsberg is designing a 2,000 sq.-ft. office building: three stories, with a basement and a rooftop. Each floor consists of about 500 sq.-ft. Everything will be done architecturally, every detail will be built out of the GGCT architectural mix, with the Rockett Glass Overlay, and Ginsberg’s designs.

“This is the holy grail that all of

us in the industry have been trying to find for 30 years.”

-Bart Rockett

BUILDING HOMES Dave Montoya of ClifRock and Lurncrete is working with GGCT for the design and construction of a quickbuild housing project for the homeless.

During his 25+ years in the concrete business, he developed a system best described as a “formless wall.” In an oversimplified way, one would add a water-reducing admixture to grout allowing the contractor to stand up without a form. The contractor would then be able to build up a 6-ft. wall and then “carve in” decorative designs.

He’s also experienced in utilizing fiberglass reinforced rebar within a panel for his decorative and residential concrete work. Rockett soon approached him to push Space Age Concrete one step further.

A sketch of a homeless shelter/ home built with the lightweight precast concrete panels.

Green Global Concrete Technologies

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You can see the glass and foam mixed within the concrete in this block of Space Age Concrete Green Global Concrete Technologies

With Montoya on board with GGCT, the team quickly found a new direction and use for their lightweight precast panels: shelters and mobile homes for the homeless. Often more traditional shelters are damaged due to criminal activity like stripping out the copper or arson.

“When I make it out of concrete,” says Montoya, “the thing is, they can’t break it. They can’t mess with it. They can’t hurt it.” The panels are mold resistant, fire-resistant, as well as provide a natural R-value (or insulation) for additional protection from the environment.

Reportedly, a single shelter can be set up in a single day with solar panels installed for electricity. Utilities like wiring and plumping would be integrated within the concrete panels providing protection from damage.

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Finally, the mobile structures were designed to be portable and modular which could potentially save municipalities a substantial amount of money vs unsustainable construction. While modular, the current design for a shelter is to have an 8 by 10-ft. (or about an 84 sq.-ft.) footprint. GGCT is in communication with some state and local governments on developing special areas for the buildings. Las Vegas and Louisiana have already shown interest.

Montoya has already worked with the military with another one of his companies, Equip-Core, for some tactical training structures utilizing the same panel-based system. The concrete is durable, strong, and patching holes from live-fire rounds can be handled by hand by a mix of the same concrete. Repaired patches are cured in 15 to 20 minutes.

Taking advantage of the Space Age Concrete potential via its lighter weight and strength, GGCT have their sights on applying the precast concrete to the construction of more than just homes and shelters. Potential products include

TEST RESULTS • After Two Days: 1,370 psi (Architectural mix) • After Seven Days: 2,370 psi (Infrastructure mix) • Weight: 2,400 lbs. per one yard of Space Age Concrete (regular concrete would weight about 4,050 lbs. per yard) PSI testing took place in January 2021. Based on preliminary data, the Infrastructure mix of Space Age Concrete should reach 6,500 psi and the Architectural mix should reach 5,000 psi. The company is still working to modify it for the better— but it’s a pretty good place to start.

According to Rockett, Space Age Concrete didn’t crack as one would expect in the compressive strength test. Instead, due to the amount of fibers used in the concrete, it had expanded instead of sheared like a traditional concrete.

a lightweight traffic sound barrier wall, steps, as well as a pedestrian bridge.

They’ve created a 4 ft. by 8 ft. mock panel of the sound barrier wall designed to look like a stone wall. Plans are to have five different designs available.

ENVIRONMENTAL IMPACT At the end of the day, the GGCT team’s goal is to empower contractors themselves through a licensing program.

In a way, to give it out to the world and to create jobs. “We want people to come on board to buy our licenses,” SECOND BIG BLUE says Rockett. “Our job is to develop Apart from aiding the restoration of this stuff so we can use it right away… our infrastructure, Rockett has also we’re going to the best guys in the world set out affect sustainability through and we’re doing it—now. a recycling initiative.

People who want to start Pulling out recycled glass building their factories, is a costly challenge for who want to get their municipalities and recycling design teams involved… centers. His vision, called we want to build green “Second Big Blue,” is to infrastructure, we have purchase the collected glass AeroAggregate as it from municipalities and the green infrastructure.

We now need the people to comes out of the kiln. townships. The concept comes Green Global build the green infrastructure. Concrete Technologies from providing a clear purpose We’re going to develop it, to recycling—for people to we’re going to show them how to build better understand the end-result of their it with our materials and they’re going area’s recycling efforts. The initiative to take it. looks to create a separate large storage “Right now there’s a major issue bin (a second blue container) for collected in sinking infrastructure across the glass at the municipality level, not the bin country,” says Rockett. “Bad spills, you put at the curb. stuff that’s 50 to 60 years old, sinking, “Right now, all the garbage is cracking, heavy weights and the way contaminated,” he says. “If we could you can achieve buildings that way get that glass separated, that would and saving billions of dollars is with save consumers millions of dollars in a lightweight material that doesn’t infrastructure for the country because need to be overengineered when you the savings could be passed back to the have 20,000 cars a day running on it municipalities. We have a product that [referring to the potential of Space Age takes the glass that you throw in your Concrete’s use in bridge construction]. garbage and you can put into something I didn’t really realize all that until like a road, a school floor, a bridge, or I started with AeroAggregates and a rock underneath I-95…at least you listened to all they are doing with all know that when you threw something their infrastructure and how light it is. away it’s going to a purpose. That’s the It’s really about going forward. To build initiative. with it.”

“We can actually start building with There’s also a reduction of carbon green products—recycled material— once you consider the factors in the right now.” makeup of Space Age Concrete together.

At the time of this writing, the The csa cement has a smaller carbon development of the Second Big Blue footprint requiring a lower temperature initiative is still on-going.

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in the kiln, utilizing a foam and recycled glass aggregate, as well as the fiberglass reinforced rebar—each plays a part in the “green” part of GGCT. For instance, due to AeroAggregate’s lighter weight, a contractor can ship 100 yards of the material at once vs 20 yards on a typical tri-axle truck. Putting this into perspective, a recent project using AeroAggregate for an airport as an aggregate saved the contractor about 6,000 trips.

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FOUNDATIONS & WALLS

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BY KIM BASHAM, PHD PE FACI

How to Evaluate & Troubleshoot

CONCRE T CRACKS

They’re either the total extent of damage or the first signs of serious trouble. Here are some recommendations for troubleshooting cracks prior to designing or performing repairs.

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racking is a natural, expected, and accepted behavior of concrete. However, cracks may affect the appearance, function, durability, service life, or more seriously, the structural integrity of the concrete. For these reasons, designers, concrete producers, and contractors are always trying to control or minimize the amount and

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severity of concrete cracking. However, crack-free concrete is seldom achievable, especially for standard unreinforced or reinforced concrete. Basically, concrete cracks. That’s a fact.

For some projects, the specifications require cracks in concrete to be repaired and may specify a crack repair procedure or may simply require cracks to be repaired as directed by the engineer. Regardless of what is required by the specifications, cracks should be investigated before designing or performing repairs, especially for elevated structures. Otherwise, repairs may not address the root cause and result in a poor repair that fails prematurely or a repair that may not restore the as-designed condition of the structure. More importantly, a proper investigation can determine if a crack is the first sign of serious trouble

indicating the load-carrying capacity of the structure may be jeopardized by either a design, detailing, or construction error.

Here are some recommendations for troubleshooting concrete cracks prior to designing or performing repairs.

THE FUNDAMENTAL CAUSE OF CRACKING There are many types of cracks related to different causes but the shared cracking mechanism for all common cracks is tension. The tensile capacity of concrete is limited for both plastic or hardened concrete. Concrete is not a ductile material; it will not stretch when subjected to tensile stresses.

When the tensile stresses exceed the tensile capacity of the concrete (about 10% of the compressive strength), concrete cracks. Of course, the tensile

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Adobe Stock Images |

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capacity increases as freshly placed concrete hardens but while plastic and at early ages, concrete has little tensile capacity so it is very vulnerable to cracking.

A crack investigation should determine the root cause of the tension.

The cause can be considered when designing or performing crack repairs.

Once the cause of the tension has been identified, the type of crack or a crack label can be assigned. Common types include plastic settlement, plastic shrinkage, early-thermal contraction, restrained drying shrinkage.

Typically, cracks are categorized as “before hardening” while the concrete is still plastic and “after hardening” or after the concrete has hardened.

Because tensile capacity increases as concrete hardens and gains strength, a third category called “early age” exists. This category refers to the time period after hardening but prior to the concrete gaining full strength. Many cracks occur when early-age concrete is subjected to tensile stresses, especially concrete volume changes associated with restrained thermal contraction (cooling) or concrete drying shrinkage.

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For slabs-on-ground, restraints include the base material and reinforcing if installed, and adjacent foundations and walls if not isolated from the slab with isolation joints. For walls and elevated slabs, connecting concrete elements act as restraints that prevent volume changes of the concrete from occurring. Restraints lock the concrete in place so that volume changes of the concrete (i.e., thermal and drying shrinkage) cannot occur resulting in tensile stresses within the concrete.

CRACK INVESTIGATIONS Ideally, a crack investigation should always start with a site visit and a detailed visual inspection.

At a minimum, do the following during the site visit: Figure 2. Example of a crack map showing crack widths in mils.

Highlighted cracks (yellow and orange) indicate two levels of crack edge spalling. Not show is the crack inventory that summarized crack widths, lengths and amount of crack edge spalling per gird squares for the floor.

Photo Credit: Kim Basham

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FOUNDATIONS & WALLS CONTINUED • Create a crack map showing the locations and characteristics of the cracks. Also, show other important elements such as joints, openings, penetrations, and restraints such as foundations, walls, columns, etc.

• Measure and record crack widths and lengths. For slabs-on-ground, measure contraction joint spacings and sawcut depths.

• Take lots of photographs.

If possible, obtain and review the construction drawings and specifications including the reinforcement details and concrete cover to assist with the visual inspection and to better understand the possible causes of the cracks and the designed crack control provisions. Obtain and review the concrete mix design, batch tickets, and any placing and concrete reports that are available. For slabs-ongrade, try to obtain the sawcut timing for the contraction joints. Also, obtain concrete curing information and review the site conditions including weather during and after concrete placement.

Obtain the time when cracks first appeared. Documentation should include sufficient information so others can fully understand the nature and severity of the cracking without visiting the project.

Photo 1. To use a crack comparator card, place it on the crack and algin line that matches the crack width, and read line width.

Photo Credit: Kim Basham

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Crack Maps Sketch the cracks and record the measured crack widths and lengths directly on printed copies of the construction drawings. Try to sketch the cracks to scale and close as possible to their actual locations. Note any crack patterns that may exist and if possible, the depth of cracks. Be neat and organized so either the actual crack map created onsite can be easily used to quantify the cracking or used to create an electronic version.

Mark locations of photographs so photographs can be used to enhance the value of the crack map.

Crack maps should contain sufficient information so a detailed crack inventory can be created for the purpose of designing and estimating the cost of repairs. For example, a crack inventory can categorize and list cracks

Figure 3. Be sure to measure crack widths and not spall widths unless measuring both.

Photo Credit: Kim Basham

according to widths, depths, locations, cracks with and without edge spalling, or other characteristics for the purpose of assigning different repair materials and procedures for each category of crack. Be sure the crack map inventory has sufficient information to accurately estimate repair costs or for repair contractors to bid on the work. Figure 2 shows an example of a crack map for a structural slab supported by beams/ girders and piles.

Crack Widths Measure crack widths using a crack comparator card or an optical crack width measurer. As shown in photo 1, use a crack comparator card by aligning the proper line thickness over the crack and noting the width of the line.

Be sure to measure the actual crack width and not the surface width formed by any crack edge spalling that may have occurred. If needed, measure the surface width where edge spalling has occurred and the actual crack width just below the surface (figure 3). Crack widths are needed to help select the most appropriate repair material and procedure. Also, it is easier to record and manage crack widths using mils

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FOUNDATIONS & WALLS CONTINUED

Photo 2. Using either screws or epoxy, mount the two-piece calibrated crack monitor on the concrete over the crack. The red crosshairs on the clear piece move relative to the grid on the white piece graphically showing the direction and amount of movement.

Photo Credit: Kim Basham

than using inches (one mil is equal to 0.001 inches, 0.004 in. equals 4 mils).

Active or Dormant?

Determining whether cracks are active or dormant is critical for designing a crack repair or more specifically, selecting an appropriate repair material and procedure. Active or "live" cracks are likely to grow in width and perhaps length or open/close with changing concrete temperatures. Dormant or "stable" cracks are unlikely to grow in width or open/close with changing concrete temperatures. Active cracks should be repaired or sealed with flexible repair materials to accommodate future crack movements. Whereas, dormant cracks can be repaired with either flexible or rigid repair materials.

Specially designed crack gauges attached to the concrete as shown in

photo 2 can help to determine if cracks are active or dormant. Of course, other factors should be considered including the age of the concrete and the amount of concrete shrinkage yet to occur, exposure conditions or more specifically, concrete’s exposure to solar heating/cooling, and daily/seasonal temperature changes that cause thermal expansion and contraction of the concrete. Also, consider the effects of loads on cracks. If in doubt about future crack movements, assume the crack is active.

Reinforced?

Depending on type and amount, typical concrete reinforcing including steel rebars, steel fibers, and macro-synthetic fibers can control crack width movements so cracks can be considered as dormant with regards to designing a crack repair procedure. It is important to determine the type and amount of reinforcing crossing through cracks during the investigation. If needed, a rebar locator can be used to verify the presence and location of steel reinforcing.

Type of Cracks There are two basic types of concrete cracks: intrinsic or non-structural, or structural. Intrinsic are natural occurring cracks that are related to concrete as a material such as plastic settlement and shrinkage, freezing of freshly placed concrete, crazing, thermal and drying shrinkage, seasonal temperature changes, corrosion of reinforcement, and alkaliaggregate reactions. Whereas, structural cracks are typically associated with overloads from either construction or service loads. These cracks typically

require an engineer’s involvement to determine if the load-carrying capacity of the structure has been jeopardized and to determine what type of repair or strengthening is required to ensure the structural integrity and safety of the structure.

The most common types of intrinsic cracking that are commonly repaired are plastic shrinkage, early-thermal contraction, and especially, drying shrinkage cracks. Restrained dryingshrinkage cracks in both slabs and walls are the most common type of cracks requiring repairs to improve the overall appearance, to provide crack edge support to prevent edge spalling, to seal cracks to keep water and dirt out, and to seal cracks in environmental structures.

Of course, the decision to repair cracks depends on the severity of the cracking, exposure conditions, and the design function of the concrete. For more information about types of concrete cracks and causes, see references 2 and 3.

Repairing Cracks After determining the root and possibly, secondary causes of cracks, an appropriate crack repair material and procedure can be selected and/or performed. Part 2 will address crack repairs and how to design or select the proper materials and procedures. Procedures addressed include: clean and fill, rout and seal/ fill, epoxy and polyurethane injections, autogenous healing, and no repair. Yes, that’s correct—no repair.

Look for Part 2 in the next edition of Concrete Contractor.

References

1. ACI 201.1R-08 Guide for Conducting a Visual Inspection of Concrete in Service, American Concrete Institute, www.concrete.org 2. ACI 224.1-07 Causes, Evaluation, and Repair of Cracks in Concrete Structures, American Concrete Institute, www.concrete.org 3. Technical Report No.22, Non-structural Cracks in Concrete, 4th Edition (2010) Report of a Concrete Society Working Party, Concrete Society, www.concrete.org.uk

For more information on repair, visit ForConstructionPros.com/ concrete/equipment-products/ repair-rehabilitation-products.

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PRODUCT FOCUS

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BY CLAIRE HILTZ

Concrete Repair Training & Online Certification Build up skilled employees with continued education and online training options.

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oncrete construction business owners have been challenged for years to put together a skilled team in the face of an ongoing workforce shortage. Resources available through ACI University can help companies develop their team’s abilities.

Not only does having a skilled team enhance a company’s marketability, but investing in employees—including helping them with their training needs and career advancement—is one of the best ways for a company to build a relationship with its workers and improve employee retention.

The American Concrete Institute (ACI) is widely known for its certification programs; the institute offers nearly 30 programs designed to form a minimum qualification for personnel employed within the concrete construction industry. For these programs, certification examinations and optional training courses are conducted through an international network of over 120 sponsoring groups. But ACI offers

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another educational path: ACI University, a global, online-learning resource with on-demand access. ACI University features ACI Certificate Programs, which offer defined courses of study in concrete materials, design, repair, and construction. Students completing a program receive a certificate from ACI as well as a digital badge demonstrating their credentials that can be shared on social networks, job search sites, portfolio pages, email signature lines, and more.

HELPING EMPLOYEES BUILD SKILLS It’s one thing to know that trained employees are beneficial to the company—it’s another to decide on a detailed action plan for achieving employee education. Following the programming laid out by ACI University ensures that training is complete, giving workers the knowledge they need to achieve quality outcomes, and it also makes the training process easier on all involved by offering systematic guidance. For example, the

Maryland's Conococheague Aqueduct was restored using a combination of historic and modern materials and methods.

Images by the American Concrete Institute

Repair Application Procedures (RAP) program is one of four certificate programs ACI University currently offers. It is easy to see how companies and their employees can approach and complete a program. The other three certificate programs currently on offer are Fundamentals of Concrete Construction, Anchorage Design, and Fundamentals of Concrete and Materials.

The RAP program covers basic concrete repair techniques, including the purpose of the repair, applications for which each method is appropriate, surface preparation, safety considerations, and repair procedures. It consists of ten courses and focuses on: Crack Repair: Courses covering crack repair include “Structural Crack Repair by Epoxy Injection,” which

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outlines the types of cracks that epoxy injection can effectively address and lists the appropriate injection equipment to use. Post-repair test procedures, which confirm a successful epoxy injection, are reviewed. The course also discusses the purpose of and who participates in preconstruction meetings.

The course “Crack Repair by Gravity Feed with Resin” identifies the types of cracks for which the gravity feed with resin method is applicable and recommends how to prepare the cracked surface for application. The course discusses the importance of concrete moisture conditions on bonding. Participants will also learn to recognize resin viscosity selection criteria, which permit the materials to penetrate fine cracks by gravity alone.

Spall Repair: The course “Spall Repair by Low-Pressure Spraying” identifies the types of repairs for which lowpressure spraying is applicable and lists the equipment necessary for the application, including safety issues related to the use of the equipment. Participants will learn to recognize the types and physical properties of repair materials.

The course also discusses the placement thickness of repair materials and the use of multiple lifts if needed.

“Spall Repair by the Preplaced Aggregate Method” describes the types of repairs that can benefit from this method of repair and explains pumping techniques and procedures. The course discusses the overall benefits of using preplaced aggregate concrete. Participants will learn to determine the proper surface moisture conditions of substrate concrete.

“Spall Repair of Horizontal Concrete Structures” gives guidelines for sawcutting size and depth for flatwork or other horizontal concrete surface repair. The course covers curing and protection considerations for spall repairs and provides repair examples.

Participants will learn to recognize the undercutting recommendations for concrete with corroded reinforcing steel.

The course “Vertical and Overhead Spall Repair by Hand Application” discusses the proper treatment of exposed reinforcement, as well as undercutting recommendations, for repairing concrete with the corroded reinforcing steel.

The course emphasizes the importance of reviewing the root cause of damage prior to the selection of a repair material and application method. Repair examples are provided.

Protecting Reinforcement: “Installation of Embedded Galvanic Anodes” explains the process by which galvanic technology protects the reinforcement in concrete. The course discusses suitable repair materials that can be used and describes proper anode placement. Participants will learn to recognize the impact of steel density on the spacing of anodes.

Surface Repair: “Surface Repair Using Form-and-Pour Techniques” identifies the types of repairs for which these techniques are useful. The course outlines the recommended maximum aggregate size and explains the necessity of moisture conditioning the repair surface substrate. Participants will learn to recognize the importance of proper preparation and curing considerations.

ACI University features ACI Certificate Programs, which offer defined courses of study in concrete materials, design, repair, and construction.

The course “Surface Repair Using Form-and-Pump Techniques” identifies the types of repairs for which form-andpump techniques are useful. It discusses pumpability requirements for repair materials and formwork pressure considerations. It also summarizes the proper sequencing of repair material placements.

“Leveling and Reprofiling of Vertical and Overhead Surfaces” assists participants in recognizing when leveling and reprofiling is an appropriate repair

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application for a concrete surface. The course discusses the selection of the correct material to use for a leveling/ reprofiling repair, application procedures for the material(s), and the surface preparation necessary before completing a leveling/reprofiling repair.

To participate in the ACI Repair Applications Procedures program, individuals must purchase the course package or be ACI members, who have free access to the program. Accounts are not sharable and courses must be completed by a single individual using the same username. Completion of each course requires an 80% passing score on the course exam and all courses must be completed within two years from the date of purchase.

Each course completed earns 0.1 continuing education unit, equivalent to 1.0 professional development hour.

Courses that are updated will still count toward the certificate program as long as they have been completed within the 2-year timeframe. Once an individual has completed a course of study, the individual can request a program certificate through ACI University.

All documents available through the RAP certificate program are also available through the ACI University allaccess digital subscription and the ACI Concrete Repair subscription.

Construction companies can set themselves apart from the competition, improve quality outcomes on the jobsite and build a more stable team by guiding employees through training. Beyond ACI’s standard certification procedures, ACI University’s certificate programs offer a convenient resource.

Claire A. Hiltz is the director of professional development at the American Concrete Institute. With more than 20 years of experience as an instructional designer and course developer working with learning management systems and eLearning authoring tools. Her team collaborates with subject matter experts to design and develop educational documents and online courses as well as coordinate the delivery of live webinars and classroom-based seminars.

For more from the ACI, visit ForConstructionPros. com/10071932.

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PRODUCT FOCUS

CONCRETE REPAIR PRODUCTS

CustomTech TechLevel WSF Fiber Reinforced Self-Leveling Underlayment for Wood Subfloors

Sakrete’s Pro-Mix line of industrial-strength, fast-setting concrete mixes allows most projects to be traffic-ready in less than an hour, perfect for repairs to utility cuts, parking lots, roads, bridges and overpasses and more. In addition to incredible speed, Pro-Mix is engineered to deliver extended working time, solving the major challenge with other fast-setting repaid mixes. All Sakrete Pro-Mix products meet or exceed ASTM C387, and require only 15-minutes to set with a high-strength finish, allowing pros to complete more work in less time.

Ideal for repairs and construction of concrete over 2-in. thick, Sakrete’s Pro-Mix Accelerated Concrete Mix is one of the ultimate pre-blended concrete solutions for indoor and outdoor applications where rapid return to service is crucial. Full-depth repairs and DOT applications can achieve a drivable surface with a compressive strength greater than 3,000 psi in one hour, with a final strength of over 7,000 psi.

For challenging concrete repairs from 1/4 in. to 6 in. thick, Sakrete’s Pro-Mix Concrete Repair was designed for horizontal, vertical and even overhead repairs. The high-strength, fast-setting mix offers strength of more than 3,000 psi in one hour and more than 7,000 psi at 28 days.

Sakrete’s Pro-Mix All Purpose Cement was designed for surface repairs that require a feather edge or larger repairs down to 4-in. deep, Pro-Mix All-Purpose Cement was formulated for an exceptional feather-edge finish. The cement features a shrink compensating mix and enhanced crack resistance for long-lasting horizontal, vertical and overhead repairs. The mix develops strength greater than 3,000 psi at one hour and 9,000 psi after 28 days.

TechLevel WSF Fiber Reinforced Self-Leveling Underlayment from CustomTech is ideal for preparing challenging concrete surfaces for the installation of floor coverings.

TechLevel WSF is a high flow formula that prevents slow drying, bond failure, crumbling and staining. Appropriate for use on concrete and other substrates as well as plywood and OSB, this SLU cures quickly and develops high early strength in pours up to 1.5-inches deep. TechLevel WSF exceeds industry requirements for substrate flatness to accommodate a wide variety of popular large format floor covering installations.

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Sakrete Pro-Mix Family

Simpson Strong-Tie FX-70-6FS Fast-Set Epoxy Bottom Seal

Simpson Strong-Tie’s FX-70-6FS fast-set epoxy bottom seal is a three-component, moisturetolerant epoxy grout designed as part of the FX-70 structural repair and protection system to facilitate same-day filling of underwater fiberglass pile jackets. By eliminating the need to build cofferdams or otherwise eliminate water from project areas, the FX-70 system drastically reduces costs while enabling piers, docks, and other harbor structures to remain in service as the pile repair is executed.

• Fast-setting epoxy formulation allowing same-day jacket filling • Water insensitivity to eliminate need for costly and time-consuming dewatering of project areas • Freeze-thaw resistant for enhanced protection from temperature fluctuations ForConstructionPros.com/21195880

The Updated CRACKBOND Concrete Repair & Restoration Product Line

Adhesives Technology Corp. updated its CRACKBOND concrete repair and restoration product line. Bonding agents for concrete repairs, coating and sealing interior and exterior slabs, and crack injection applications, CRACKBOND products were engineered with industry-leading formulations that provide fast and simple solutions to the end user.

“Concrete repair and resoration materials have been an area of increasing focus for ATC over the last 8-10 years, both in terms of launching innovative new formulations and adding new approvals and certifications to the existing product range,” said T. J. Bland, Professional Civil Engineer and President of ATC. “The product range marketed under the CRACKBOND name gives contractors, engineers and distributors the benefits of world-class products and approvals, coupled with personalized expert service levels that have long been the trademark of ATC.” ForConstructionPros.com/21199074

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SpecChem Duo Patch

A two-component, polymer modified concrete repair mortar with integral corrosion inhibitor for use in horizontal, form and pour and when mixed to a stiffer consistency, vertical and overhead applications.

For use in industrial warehouses, parking decks, roadway applications subjected to heavy loads and abrasion, decorative overlays, resurfacing worn concrete walkways, horizontal and vertical repairs and resurfacing slabs that have been rained on.

• Contains integral corrosion inhibitor • Suitable for repairs from featheredge to 2 in.

• Interior/exterior overlayment applications • Excellent durability and adhesion • Excellent freeze-thaw durability • Easy to trowel, high slump consistency • Dries to natural concrete gray color • Ability to change consistency to loose or stiff to match application ForConstructionPros.com/21195504

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Euclid Chemical EUCOWELD 2.0

EUCOWELD 2.0 is a liquid latex bonding agent for cementbased repair mortars and concrete.

EUCOWELD 2.0 has a long open time, and repair materials can be placed either after it has dried, or while it is still wet. This bonding agent represents a new generation of easy-to-use latex, which exhibits drastically improved performance and stability in comparison to the typical re-wettable ethylene vinyl acetate (EVA) bonding agents currently available. EUCOWELD 2.0 is a unique, non-EVA based latex that utilizes reactive chemistry for bonding, rather than depending on the moisture content of the repair material.

• Excellent bond strengths • Repair materials can be applied wet-on-wet, or after it has dried • Applied to surface straight from container • Long open time

Textured Concrete Sealant from DAP Offers Textured Finish for Seamless Concrete Blend

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VanguardOnline.com FEBRUARY/MARCH 2021

CONCRETE CONTRACTOR 27

2/13/21 9:35 AM

DECORATIVE CONCRETE

»

BY JEFF HERSHBERGER

Repairing Stamped Fixing some of the common problems and a few techniques you can try the next time you are faced with a challenge.

I

n the time that I’ve been involved with decorative concrete, we have experienced tremendous growth in the industry. The consumer demand, as well as the skill and craftsmanship of those who install it, are leaps and bounds ahead of where they were just 15 years ago. As a former installer and now trainer I’ve seen a lot of stamped concrete both good and bad. In my opinion, one of

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the biggest things that separate high-end decorative contractors from the rest of the pack is the ability to know what can be repaired and how to go about it.

FIXING PROBLEMS While we all prefer things to just go as planned during the pouring and stamping process, we do still live in the real world and we all know how unpredictable a concrete project can be.

Things like temperature, sun and shade lines, or getting caught in the rain, as well as a number of other issues, can come up. There might not be anything you can do to control the weather, but you can learn how to fix some things after the fact.

Repairing stamped concrete requires knowing what can be repaired and how to go about it. Case in point, there might be times that you will need the buffer and muriatic acid to handle color repair.

Images courtesy of Deco-Crete Supply

Surface Cracks Surface cracks have always been a battle for the stamped concrete contractor.

Especially in the spring and fall when days are warm, and the nights are cool.

Knowing how to control the surface from crusting over can certainly go a long way in avoiding this, but some days it just doesn’t seem to matter how

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2/13/21 9:38 AM

Take a small amount of the same color hardener (if you used one) for your base color and run it through a bucket sifter.

This should remove the large sand. Mix the fine powder with water until you have a puddy.

One thing to remember is that the ball-peen hammer technique requires less time and effort than the slurry technique. Fix as many cracks as you can the next day with the hammer and only resort to the slurry when you have to.

Blowouts or Chips

A 17-in. low speed floor buffer with a scrubbing pad works great for pulling off more release. If you don't have access to a buffer machine, a light muriatic acid wash with some hand scrubbing can also be effective.

hard you try; you still end up with a few cracks on the surface of your concrete.

Here are two things you can try next time this happens to you.

After you’ve washed the release off your concrete grab a ball-peen hammer.

Using the ball end of the hammer, start to tap on and around the cracks in a motion that would close up the crack. If you have never tried this before, you will be pleasantly surprised at how many of those annoying little cracks you can get rid of using just this method alone. This always works best the day after pouring, and keep in mind that after the concrete cures out for a few days this will no longer work.

Sometimes even the ball-peen hammer can’t fix everything or maybe you missed a few the day after the pour. There is one more thing you can

do to solve this problem. If you used a color hardener for your base color, then simply take a small amount of that same color hardener and run it through a bucket sifter to get rid of the large sand. Then mix the fine powder with some water until you have a puddy like consistency. Use this mixture to fill in the cracks. Make sure to have a damp rag with you to clean up any excess slurry in unwanted areas.

Let the slurry completely dry before antiquing or sealing. If you had used integral color for your base, it will be hard to find a color hardener that will match your integral color exactly. The best thing to do is to get the closest one you can find and have a second or even third color to lighten or darken things up as needed. you will need to experiment with the dosage to get the best color match.

It may seem counter-intuitive to the process, but using a ball-peen hammer to get rid of those annoying little cracks.

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This problem could come from the surface drying out too fast or maybe you ended up dragging a stamp or two when you were picking them up. Either way, if you stamp enough concrete this is bound to happen, and they will need to be repaired.

Using something cementitious to patch these little guys up is the only real way to fix them. The challenge is getting the patch to look as close as possible to the color of the concrete. With color hardener, this is really easy. Just take a hand full of the same color hardener you used for the pour and follow the sifting and mixing instructions we went over in fixing surface cracks.

Though, you will need to treat things differently

FEBRUARY/MARCH 2021

CONCRETE CONTRACTOR 29

2/13/21 9:38 AM

DECORATIVE CONCRETE CONTINUED After applying an antiquing agent to a clean slab, let dry for 24 hours and continue with resealing.

When preparing the patch material for issues like a popout, look for a puddy feel with the consistency of a peanut butter.

Remember to apply a bonding agent to the your concrete first.

when it comes to finishing off the patch.

We will be dealing with a larger area to repair and just wiping the excess off with a rag is not going to look very good. For smaller blowouts and chips, smoothing the patch out with your fingers or a small trowel should solve the problem. Texturing the patch may be required for larger repairs.

In the case of integral color follow the tips for color matching described in the crack repair section.

Color Variations Color variations can be caused by a multitude of different things and, once again, some of them are out of your control. The first thing we need to do is decide if the problem is in the concrete itself or just on the surface.

Color variation on the surface generally comes from inconsistent washing of powder release. Sometimes the release sticks harder in certain spots than others.

Top: With blowouts or chips around the edges of grout lines, smooth out your patch with your fingers or a small trowel. A rag is not recommended.

Bottom: With small patches, using your hand or a small trowel will smooth out the spot. The challenge here is in the color. Be sure to get the patch to look as close to the concrete as possible.

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FEBRUARY/MARCH 2021

This will make the concrete look darker or lighter in those areas. This can also happen when you make mutual pours on the same project. Even if the two slabs were poured the same day, one might still look different than the other. These problems can easily be solved by washing more release off the slab. If you have already gotten as much off as possible with your power washer then it's time to get another tool or some muriatic acid involved. A 17-in. low-speed floor buffer with a scrubbing pad works great for pulling off more release. If you don't have access to a buffer machine a light muriatic acid wash with some hand scrubbing can also be effective. It is important to dilute your muriatic acid with water so

that you avoid damaging the surface of the concrete—ten parts water to one part muriatic is a good place to start. You can always add more as you go if needed.

There might even be times that you will need the buffer and acid to get rid of the variations in the color.

If the color variations are in the concrete itself, more drastic measures will need to be taken. These variations can be caused by not applying enough color hardener, improper dosing or mixing of integral color, or sometimes inconstant curing. No matter what the cause, the repair will involve some sort of re-coloring. For minor variations, you might be able to hide it with some antiquing agent. More drastic variations will probably require a stain or overlay. The products best for the job will depend on what part of the country you live in. A stain that works great in southern California might not hold up long-term in Minnesota. Make sure to work with your local supplier for the best longterm solution for your area.

Texture Of all the things that can be repaired on a stamped concrete slab, the texture is not one of them. You only have one shot at this, and you need to nail it the first time. One of my favorite lines by Jason Geiser, decorative concrete contradctor, educator and owner of Deco-Crete Supply, is “Never sacrifice texture.” On hot and sunny days this might mean letting some of the details go until after you’re done stamping or even the next day.

RESTORING STAMPED CONCRETE Stamped concrete, like all concrete, will need to be maintained and mother nature will take its toll over the years.

While simple cleaning and maybe even resealing may be done by the end-user, there is still a lot of work out there in the field of stamped concrete restoration.

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2/13/21 9:38 AM

n

A job well done.

Stone Popouts One thing you will frequently notice especially in freeze-thaw conditions is stone popouts. Although there’s not a whole lot you can do to avoid this, they can easily be repaired. Follow the same process described in the blowouts and chips section.

Resealing Resealing is the most common form of stamped concrete maintenance. In most cases, this needs to be done every three or four years. Resealing stamped concrete can be a tricky business so make sure you know what you are getting into.

Proper cleaning and prep work, using the right sealer, and application techniques are all essential for long-term success when resealing stamped concrete.

before sealing. The other benefit of sandblasting is that it opens up the pores on the surface of the concrete just enough to let the new coat of sealer bond even better.

With the stamped concrete industry still growing every year, the repair techniques for installers are also still evolving.

The tips in this article are a great place to start but are certainly not the end of the road.

Jeff Hershberger is a training and store expansion lead for Deco-Crete Supply.

For more information on stamped repair, visit ForConstructionPros.com/21220835.

Reapplying an antiquing agent is an easy fix should the end-user let the sealer completely wear away.

Antiquing There might be times that the end-user has let the sealer completely wear off and some or all the antiquing is gone.

This is really an easy fix and it's a better problem to deal with than if the slab was oversealed. Apply some antiquing agent after the slab has been cleaned, let it dry for 24 hours, and continue on with resealing.

Sandblasting If things have gotten to a point where there is a heavy buildup of sealer from over-applying.

Or if the wrong type of sealer was used, just cleaning and resealing will actually add to the problem. The only way to permanently fix this is to remove all the old sealer and start over. The best way we have found to accomplish this is by sandblasting. This does a great job of Should you find a removing the existing sealer in a fairly buildup of sealer from short amount of time without damoverapplication or the wrong aging the texture. Sandblasting will sealer was used, pull out remove most or all of the antiquing your sandblaster and start however and will need to be reapplied over. Remember PPE.

www.ForConstructionPros.com/Concrete

CONC0221_28-31_Dec.indd 31

FEBRUARY/MARCH 2021

CONCRETE CONTRACTOR 31

2/13/21 9:38 AM

DECORATIVE CONCRETE

»

All photos: Alchemy Concrete Inc.

BY JONATHAN KOZLOWSKI

LAKESIDE

MAGIC

Alchemy Concrete’s under 5,000 sq.-ft. award-winning work.

C

hange is inevitable. This could be an unwelcome happening or exactly the push needed.

In the small town of Nelsonville, Wisc., you’ll find a decorative concrete contractor harnessing every skill they have to take concrete and make it beautiful. The town is a small market (population 155 according to the 2010 census) but the area hosts lake homes and vacation houses—opportunity for a decorative concrete contractor.

While in college Judah Haas, president of Alchemy Concrete Inc., started out like many contractors had—working for local concrete contractor. In 2001, he started a small flatwork business and ended up buying out the contractor three years later in 2004. “He got into more foundations and we were growing,” says Haas. “So, we formed a new company: Alchemy—the power and process of change.” It’s this ability to accept change as it comes, adapt, and to create beauty just may be the secret to their magic.

According to the company, they pour

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colored concrete every day; 70% of their business from specialty or decorative concrete or “high-end backyards” with supplementing the business with foundations, regular driveways, and patios.

One of these high-end backyards earned them 1st place in the 2020 American Society of Concrete Contractor’s (ASCC) Decorative Concrete Council’s (DCC) Decorative Concrete Awards competition in the “Cast-in-Place Stamped” award for a project under 5,000 sq.-ft. The project ended up exemplifying Alchemy’s ability to handle change.

According to Chris Sullivan, a decorative concrete specialist from the ASCC, Alchemy’s team earned its recognition through the project’s overall size, scope, and producing a wide range of stamped decorative finishes on one project is a significant challenge with fantastic quality. Judges recognized the skill and work done in the project through the realistic use of color and texture. One commenting, “this is as much art as it is science and process.”

“Overall this project impressed the judges as a great example of what high

quality stamped concrete should look like,” says Sullivan. “It was an example of the best of all aspects of decorative concrete work.”

The DCC Awards have become one of the largest and most prestigious award programs highlighting the best of decorative concrete worldwide. There were over 120 entries in the 2020 program in 11 categories.

According to Sullivan, the program’s purpose is to highlight the industry and the beauty that can come from concrete. “We also highlight the installers and showcase their award winning work across multiple media formats. The goal is to continue to grow the program, encouraging more companies to enter projects for consideration.”

Submitted projects are reviewed by aesthetics, craftsmanship, functionality, creativity, and safety. The program is open to ASCC and non-ASCC members. The 2021 award program entry deadline is March 31. Awards are planned to be presented at the ASCC Annual Conference in an in-person in St. Louis, Mo. late Sept. 2021.

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2/13/21 9:42 AM

A WORK OF ART Starting the lake home project, Tom Dunbar, Alchemy Concrete Inc.’s director of design and landscape architect met with the client in December 2018.

“Originally it was just extending their driveway doing decorative with borders and decorative colored panels,” he says. It grew from there.

It went from that to adding a walkway in the back, adding a patio, adding a walkway and stairs to the lake, adding steppingstones around the back of the house, adding new steps, to working on a new driveway along the road. “From the time we started this to the time that we finished it, it went from the road…right down to the lake,” says Dunbar.

“These guys are really good at designing on site and helping customers,” he adds, referring to Haas and Alchemy’s director of operations, Charlie Wanty. “They help ‘see’ what it could be. It’s that interactive process and on [this] project it never stopped.”

What started at a $35,000 project, blossomed to about $160,000—including all unplanned issues along with. With a few hold ups along the way, it ended up being a three to four month long process completing in the spring of 2019.

Among the many unique features in the project, the client wanted to get hands-on. Poured and cast in the Alchemy shop with the owner, she designed a table featuring a dragonfly made of colored glass (see inset photo pg. 30).

Besides the structural wall going down to the lake, almost every part of the project included a type of stamping. They used a slate texture from an Oxford slate stamp by Butterfield Color. “We had different colors going up with different pieces of it, but it had the same texture through the whole thing so it was kind of seamless there,” says Haas. They take the stamp into the consideration regarding saw cuts and design, says Dunbar. Placing them at just the right spots to allow the cuts to act as part of the pattern itself.

They used a 4,000 exterior blended mix of Ready-Mix with a small fiber

for shrinkage control and cracking and BASF colors.

Additionally, the project included stepstones hand-carved from concrete creating a sidewalk on one side of the house.

CHALLENGES One challenge came from the lake’s high water. At the time of construction, it was up two to three feet above normal levels. “There’s a lot of zoning and ordinances,” explains Wanty.

“We had to meet with the county and set backs and water high marks. The water [had] been as high as it’s ever been.

We had to have a water shed plan and then there was township. We actually didn’t do a small portion of the project because of some township ordinances, so there was a lot of navigating square footages and pervious area.”

Having been working in Wisconsin for over a decade now, Alchemy’s no stranger to these situations, handling permits, zoning, as well as understanding how to deal with the site, the environment, the typography, the soils, and rocks are all part of the process.

A part of the project did require some shoreline restoration at the lake. Overcoming this challenge, Alchemy used envirobags (70% sand and 30% black dirt) to build a living retaining wall so it could “grow” into the shoreline over time. Unfortunately the high water did not allow the use of heavy machinery so much of the work was done by hand.

Here, they had to act as landscapers, shoreline restoration experts, as well as concrete guys. “We had to [build] that retaining wall underwater,” says Wanty.

“Because this project quadrupled… the shore line wasn’t part of the original [plans]—if we wanted it done, the Alchemy team was going to do it. With subcontractors being so busy, 3, 4, 5, 6 months out—getting a shoreline guy out there wasn’t happening.”

Stormwater management had to be a special consideration. Alchemy worked with the county to control where stormwater went. Because the work was so near the lake, they had to be sensitive that the water did not run into the lake

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CONC0221_32-33_DecProfile.indd 33

and special grading was done at the front of the house to divert the water.

The total flatwork was 4,350 sq.-ft.

Pumping was subcontracted to local contractor Potratz Concrete Pumping.

Due to the decorative need, placements were done in smaller pours instead. To get more control over the design and accomplish the required finished product, Haas explains that they typically pour their borders first and dowel those slabs together. “For instance, we’ll put all the borders around…we’ll do four pours every hour and a half—three yards vs 12 yards at once,” he says.

The original plan featured solar lights at the entrance. A feature that proved troublesome due to the location’s surrounding trees. Solar wasn’t going to work and needed to be switched with wired lighting. “That held us up for a week or two. We were done with work and ready

to pour. Iit got all tore back up again for lights. But it was worth it,” says Wanty.

“That’s part of what we do, we respond to the situation, to the client,” says Dunbar. Maybe there lay the magic ingredient to Alchemy Concrete Inc.’s success—having the skill to not only change concrete into something beautiful but the willingness to change to meet the needs of the project as well as the client. “That’s what we’re good at,” he says.

Haas agrees. “You have to learn to say, ‘you can do this and you can’t do this.’ We have the patience. You can create some incredible things with good people. That’s the key to success in business. That’s what were’ trying to do. You do that first and everything else comes.”

More on decorative concrete can be found at ForConstructionPros. com/concrete/decorative.

FEBRUARY/MARCH 2021

CONCRETE CONTRACTOR 33

2/13/21 9:42 AM

BY JONATHAN KOZLOWSKI All photos are courtesy of WerkMaster

THE FIRST STEP IN CHOOSING THE RIGHT

ABRASIVE

In surface preparation, there are a number of things to consider when selecting a metal-bond diamond abrasive. First, start at the concrete floor and figure out what you’re working on.

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O

ne of the most common mistakes a contractor can do with a new concrete grinder is not take any training for it. There’s a lot you can learn with videos online, but in order to really understand polishing or concrete grinding it’s recommended to get training from the manufacturer of the product you own. Each type of grinder has its own features, its own benefits, its own performance. If you don’t know exactly what your machine can do, you might not get the intended result—which can cost you time and money.

FEBRUARY/MARCH 2021

On top of that, making sure you choose the right abrasive tooling for the job can greatly affect how effective you will be. Use the wrong bond on the wrong slab and you’re back to grinding into your deadlines and eating away at your profits. “There’s two sides to it, it either is going to cost you more time, or it’s going to cost you money in tooling,” says Brian Wilson, President of WerkMaster, a manufacturer of concrete surface preparation equipment. WerkMaster conducts regular training sessions for customers and non-customer contractors.

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2/13/21 9:45 AM

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CONC0221_34-37_PC.indd 35

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commercial retail or industrial site, is to take a piece of paper and lay out a pencil drawing of what the floor plan looks like,” says Wilson. “Cut it into quadrants. If it's 5,000 sq. ft., cut it into four. You want to scratch at least two places in each of those quadrants.”

TIPS • Ask your manufacturer about training.

• Know the hardness of your concrete.

• Do a sample.

• Re-check the hardness of your concrete as you work.

• If you call for help, take photos.

“For example,” he says, “let’s say 1,000 ft. takes an hour to grind.

As [the concrete] gets harder, when they get into the seven, eight and nine concrete—that time can change from one hour to two, three, and even up to four hours. Same machine. Same tooling. Wrong bond.” This also applies to using a mismatched tooling on softer concrete.

Before rolling out the machine onto the floor, Wilson strongly advises in understanding the concrete floor you’ll be working on first. One such way in doing so is with a Mohs harness test kit. Knowing how hard your concrete is pivotal to choosing the right abrasive for the job at hand.

The Mohs Hardness Scale rates concrete on a scale nine to one and it’s at the high and low extremes where complications arise. Hard concrete (nine, eight, or seven) produces a fine dust. WerkMaster explains, “This dust is not abrasive and does not wear the metal matrix of the diamond segment sufficiently.

The result is that the diamond grit soon becomes exposed. The segment stops grinding and the segments can get hot and glaze over. A tool with a soft bond is required in order to stay dressed and expose diamonds in order to keep cutting.

“Grinding soft concrete [rated at three, two, or one] requires ‘hard bond’ tool that resist the metal matrix being eroded to quickly from

36 CONCRETE CONTRACTOR

THE MAKE-UP OF A TOOLING

the abrasiveness of the cement dust.

The sandy and abrasive dust will erode tools quickly. Grinding soft concrete is when contractors fail be aware of the signs of rapid grinding and fast wear to their tooling.”

Concretes at a six, five, or four hardness are considered medium.

Location matters. Hardness can vary depending on geographic locations although one should only use it as a guideline.

For example, Arizona concrete is known to be harder due to the volcanic rock in the concrete.

Meanwhile, due to the shells commonly used, the concrete in Florida is typically much softer.

Regardless of where you’re working since you don’t know exactly what was done at the batch plant, Wilson stresses the value in continuously scratching your concrete. “It’ll give you an indication of what you’re up against,” he says.

Note the project you’re working on. While residential pours may have been done in one, larger commercial placements might have been done in different times of the day with different temperatures, sitting in a mix-truck longer, a slightly different formulation, etc.

“What we recommend is in any

FEBRUARY/MARCH 2021

The rule of thumb: use a hard bond on soft concrete; use a soft bond on hard concrete; and a medium bond on a medium hardness.

“A metal bond diamond abrasive is a formulation of different types of metals,” explains Wilson. It is here where the difference comes in between soft-, medium-, or hard-bond tooling. The metal and diamond mix is then formed into various molds, shapes are specially designed for different uses.

The size of the diamonds suspended in the metal will direct how aggressive the tooling will be. This should be depicted by the tooling’s grit number. “The lower the number, the bigger the diamond,” says Wilson. The higher the grit, the smaller the diamond’s size in the diamond-to-metal bond make-up of the tool.

While there are some natural diamonds used in tooling, they are typically man-made. The quality of these man-made diamonds can greatly effect price. Lower quality diamonds may wear quicker and may not cut the same.

While surface preparation can be going swimmingly at 1,000 sq. ft. an hour, this efficiency can significantly drop if you’ve mismatched the bond level. You’ll be burning through tooling quicker than necessary. Not to mention the increased labor-hour cost at the end of the day.

www.ForConstructionPros.com/Concrete

© 2021 Grac

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2/13/21 9:45 AM

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2/15/21 8:37 AM

SPECIFICATION GUIDE: POWER TROWEL

9 TROWELS FOR THE RIGHT FINISH Technical data to help you choose your next power trowel.

7.

2, 3.

1.

9.

4.

5, 6.

8.

Model

Walk Behind or Ride-On

Weight (lbs)

Troweling Diameter

Rotor RPM

# of Blades

Steering: Mechanical/ Hydraulic

Handle Options (Walk Behind Only)

Engine HP

Fuel Type

More Information

1. Toro PT-46PP Power Trowel ProPitch

Walk Behind

239 lbs.

46 in.

N/A

4

Manual

Adjustable

N/A

Gasoline

ForConstructionPros.com/ 10879819

2. HoverTrowel High Torque Air

Walk Behind

42 lbs.

25 in. or 34 in.

0-60

3

Mechanical

Telescoping

I-R .76 hp

Pneumatic

ForConstructionPros.com/ 12039894

3. HoverTrowel Low Torque Air

Walk Behind

38 lbs.

25 in. or 34 in.

0-60

3

Mechanical

Telescoping

I-R .41 hp

Pneumatic

ForConstructionPros.com/ 12039894

4. MBW F36

Walk Behind

183209 lbs.

37.5 in.

70-135

4

Mechanical

Stanard, LowVibe, and EZ Pitch

GX160 or GX270

Gasoline

ForConstructionPros.com/ 12169700

5. MBW F46 High Torque

Walk Behind

267 lbs.

47.6 in.

35-180

4

Mechanical

EZ Pitch

GX390 High Torque

Gasoline

ForConstructionPros.com/ 12169700

6. MBW F46

Walk Behind

246260 lbs.

47.6 in.

70-135

4

Mechanical

Stanard, LowVibe, and EZ Pitch

GX270 or GX390

Gasoline

ForConstructionPros.com/ 12169700

7. Superabrasive Lavina LP36

Ride-On

1,422 lbs.

2 x 36 in.

0-185

4 per rotor

Mechanical

n/a

35 hp (999 cc, 61 cu.in.)

Propane

ForConstructionPros.com/ 21113442

8. Kipper Crete KPR-11.5-CP Pan

Handheld

16 lbs.

11.5 in.

0-700

6

Mechanical

n/a

n/a

n/a

ForConstructionPros.com/ 21244759

9. Multiquip LD6SL

Ride-On

865 lbs. (opp. weight)

75 in.

0-140

4 per rotor

Hydraulic

n/a

23 hp

Gasoline

ForConstructionPros.com/ 21112985

38 CONCRETE CONTRACTOR

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FEBRUARY/MARCH 2021

www.ForConstructionPros.com/Concrete

2/13/21 9:52 AM

Titen Turbo You’ve got to drive it to believe it. ™

Reliable installation. Less torque. Superior holding power. Meet the Titen Turbo, Turbo™, the next-generation concrete and masonry screw anchor from Simpson Strong-Tie. Its revolutionary Torque Reduction Channel traps dust where it can’t obstruct the thread action, drastically reducing binding, stripping or snapping.

For a fast, easy and high-strength fastening solution, try our new Titen Turbo screw anchor. Visit go.strongtie.com/titenturbo or call us at (800) 999-5099 to learn more. ©2021

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Simpson Strong-Tie Company Inc. TNT20

2/15/21 8:42 AM

Idea File

SUPRASHINE

THE NEW GENERATION OF FLOOR MAINTENANCE PADS

ALL-TEX SUPPLY

EQUIPMENT & SUPPLY

40 CONCRETE CONTRACTOR

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Idea File INTRODUCING SAKRETE PRO-MIX: the highest-strength, fastest-setting, most workable repair mixes available on the market. Engineered for the most demanding applications, Pro-Mix products feature set times of under one hour, 7000+ psi final strength and extended working time to give you the best possible finish. finish Now available at Lowe’s nation-wide. Learn more at SakreteProMix.com

Let Tekla Structures Help You Avoid Hidden Dangers Sometimes the scariest hazards for a concrete contractor are the unseen dangers to your bottom line like inaccurate estimates. A lack of confidence in your estimates can lead to non-competitive bids or worst, a winning bid that doesn’t result in achieving your target margin.

Visit www.tek.la/ hiddendangers to learn how Tekla Structures can help.

www.ForConstructionPros.com/Concrete

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Idea File

Go Green With The Rockett’s

THE NEW GREEN TERRAZZO FLOORING Made From 100% Curbside Recyclables Quality Assurance By Patented Specs First Team Of World-Class Factory Installers Clean-Up Made Easy; Just Use Soap And Water!

WWW.ROCKETTGLASSOVERLAY.COM INFO@ROCKETTGLASSOVERLAY.COM CALL US TODAY: 844-7ROCK-00

TITEN TURBO™ CONCRETE AND MASONRY SCREW ANCHOR The new time-saving Titen Turbo from Simpson Strong-Tie features a pointed tip and serrated leading threads that provide easier, faster installation when anchoring through wood into concrete.

Its innovative torque-reduction channel drastically reduces installation issues like binding or snapping — without compromising strength.

WWW.STRONGTIE.COM

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Idea File

Verify ACI Certification The American Concrete Institute’s Certification Verify app allows users to quickly and easily verify the status of ACI-certified individuals through three search options: (1) verify an individual’s certification ID number, (2) search by an individual’s name, and (3) find the total number of ACI-certified individuals in an area.

Accessible through a phone or tablet, the app is the perfect tool to use on the jobsite to verify the status of people working on a project. Using the same functionality of the popular concrete.org/verify webbased verification tool, the ACI Certification Verify app helps the entire verification process become more seamless so jobs can keep moving forward.

Download now in the App Store and Google Play.

Learn more about ACI Certification at whyACIcertification.org.

MINNICH’S LEADING-EDGE TECHNOLOGY OFFERS HIGH-QUALITY SOLUTIONS FOR CONCRETE CONTRACTORS Minnich Manufacturing, the leading manufacturer of concrete dowel pin drills, concrete vibrators and vibrator monitoring systems, is dedicated to helping concrete contractors maximize efficiency.

Minnich’s Stinger and Controlled Speed Vibrator (CSV) are just two examples of how the company’s concrete innovations serve customers.

The light yet rugged Stinger electric flex shaft concrete vibrator is a 14.5-pound double-insulated universal motor that can drive the full line of Minnich vibrator shafts and heads from ¾ inch to 2 ½ inches.

The CSV enables contractors to communicate using their cell phone’s Bluetooth to select set speeds of vibrations per minute (VPM) in coordination with the concrete slump being poured.

Minnich will continue to bring products to the industry that support the findings of concrete research facilities across the country.

For more information, visit www.minnich-mfg.com

www.ForConstructionPros.com/Concrete

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Idea File INDEX ADVERTISER ................................................PAGE American Concrete Institute ....................................................... 7, 43 Brokk ........................................................................................... 13, 44 Graco Inc. ......................................................................................... 37 Minnich Mfg. .............................................................................. 43, 48 Rocketts Glass & Concrete Overlay ...............................2-3, 2, 46-47 SafeBasements Inc. ......................................................................... 31 Sakrete of North America ........................................................... 9, 41

NEED TO GET A CONCRETE REPAIR PROJECT DONE FAST?

Salsco Inc. ......................................................................................... 44

A Hydrodemolition robot can complete the job 25x faster than jackhammers.

Superabrasive Inc. ..................................................................... 35, 40

Simpson Strong-Tie Co. Inc. ..................................................... 39, 42

Tekla Structures .......................................................................... 21, 41 Vanguard ADA Systems .................................................................. 27

Distributed by:

Brokk Inc. | 1-360-794-1277 info@brokkinc.com | www.brokk.com

White Cap Supply Holdings LLC ................................................ 5, 40 Wirtgen America Inc........................................................................ 23

Introducing for 2021, The TPC Guidance Controlled Slipform Concrete Paver The TPC is operated via a Radio Controlled Belly Pack instrument box. In auto mode, the machine will follow the guidance string and adjust tracking and screed elevation automatically.

The screed comes in different widths from 48” to 96”. The TPC eliminates the need for forms. Just grade and set the string line!

Standard Features • The conveyor can be moved to feed the machine from either side.

• The hopper has an auger inside to be sure the material fills both sides of the hopper.

• The hopper has two hydraulic cylinders which raise the hopper and screed for transport and easy loading on the trailer.

• The 74 HP Hatz German engine is EPA compliant in all 50 states and delivers plenty of power.

• This engine, coupled with a proclaim pump, will give the hydraulic power needed year after year.

• This is a machine designed with only the basics needed to slipform the walk or pad with no forms required. By designing the TPC this way, we were able to cut the cost and make it affordable for everyone, not just the big guys.

MADE IN THE U.S.A.

44 CONCRETE CONTRACTOR

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105 School House Road Cheshire, CT 06410, 800-872-5726, 203-271-1682

www.salsco.com

www.ForConstructionPros.com/Concrete

2/13/21 9:55 AM

BY BRAD HUMPHREY Pexels

W ➊

THE OWNER DOESN’T PLAY IT SAFE! This might surprise you but I have not found one successful contractor who played things safe and overly conservative. These owners are not foolish but they often attempt new services or challenge tough markets when some of their leaders are suggesting the opposite. Consistency at being a “Top Contractor” is reinventing the company to better adapt to what the market needs ... This "Top Contractor" owner is simply motivated by situations that are full of obstacles and “No” signs spread across the path.

➋

A CLEAR VISION EXIST AND IS KNOWN BY LEADERS The most successful contractors I’ve been exposed to are normally very clear about their path, the direction, and what they are trying to achieve. Sure they make up a little along the way—these owners are not focused on the minute details—but they see where they want to go and work hard to get their leadership on board and moving in the same direction.

CONTRACTORS HIRE SMART PEOPLE AND LEVERAGE THEIR STRENGTHS I’ve watched very successful owners display the greatest patience with one of their leaders who was, in my opinion, just a “nut.” The individual was either brilliant but couldn’t communicate their intentions or expectations or the individual was

a royal “pain the @$$.” In some cases I talked with the contractor about getting rid of the "nut" leader or worker only to be informed by the owner that the individual I was recommending to be fired was perhaps the smartest worker on the team.

The “Top Contractor” knows more about reading the real profile of a contributor to the team than most psychologist and, at times, this humble consultant!

➍

THE “TOP CONTRACTOR” UNDERSTANDS HOW TO SELL THEIR COMPANY Simply put, the successful and “Top Contractor” knows best about what their company can really do and knows how to sell what they do to obtain more work. I’ve witnessed such owners pick up the phone to call a customer—who just yesterday told one of their estimators that they were going with another contractor’s bid—and influence the customer to rethink their decision and to allow the “Top Contractor” to adjust their bid to get the work. Unbelievable…but I’ve seen it done on multiple occasions.

➎

THE “TOP CONTRACTOR” IS NOT TIMID OR INTIMIDATED There’s just not very much that this "Top Contractor" is timid about or too intimidated to do. It is not arrogance but instead such tremendous confidence in their company’s abilities and capabilities that these owners almost feel untouchable.

I have heard comments like the following: “Brad, with the team I have put together, I think we can do anything!”

A spirit of personal confidence and confidence in their staff is very common among the “Top Contractor.” And why shouldn’t the Contractor feel such confidence? Because they probably assembled their “A-Team.”

www.ForConstructionPros.com/Concrete

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THE LAST PLACEMENT

Traits of Top Contractors

hat traits do “Top” contractors possess? What do they do that other contractors either cannot seem to achieve or have little clue as to where to begin? Let’s take a look at five traits that appear to be present in successful contractors.

➌

«

One final observation that I’ve made over the past 25 years of consulting is that the more successful a contractor becomes the greater their effort to build strong work processes and communication links. Why? Because as you grow your business you will begin to hire more people who may need more methodical processes and procedures to accomplish their work.

Hopefully you will see in your company three or four of these "Top Contractor" traits. Some readers might even relate to all five traits. However, if you find that you really cannot relate to more than one or two traits then you need to do some serious analysis and determine what you need to embrace.

And if you, the owner cannot relate to most of the five traits presented, then you may want to find those individuals who do possess the traits and empower them to execute their trait.

Shoot to be a “Top Contractor” wherever you are and in whatever service specialty you practice. Being “Top” status gives you a great public relations advantage as well as boosting your workers’ confidence and motivation!

Be in that class of "Top Contractors!"

Brad Humphrey is President of Pinnacle Development Group, a consultant to the construction industry. For more information about Brad’s company please visit www.pinnacledg.com or go to your App Store, type in Pinnacle Development Group and download the best educational and development App to the construction industry.

For articles, podcasts and more insight from Brad Humphrey, visit ForConstructionPros. com/10116722.

FEBRUARY/MARCH 2021

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GGCT GREEN GLOBAL CONCRETE TECHNOLOGY

GGCT, Green Global Concrete Technology is a group of Concrete/ Infrastructure Professionals who are creating and building infrastructures with curbside recyclables

HERE AND NOW!

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2.1

MEET OUR PARTNERS:

Send us your ideas and blueprints and we will bring them to life for you

TODAY!

WWW.GREENGLOBALCONCRETETECHNOLOGIES.COM WWW.ROCKETTGLASSOVERLAY.COM • INFO@ROCKETTGLASSOVERLAY.COM CALL US TODAY: 844-7ROCK-00

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THE STINGER The Stinger electric flex shaft vibrator is rugged, lightweight, and powerful. The 115v electric motor has been designed to run cool with the power and torque to handle todays concrete loads.

The stinger attaches to competitor core and casing with quick disconnect adapters.

www.minnich-mfg.com

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