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CATERPILLAR Cold Planers
SECTIONPaving Pages 29-43
For more information on paving, compaction and milling equipment, as well as comparison charts, visit CEG's Web site at www.constructionequipmentguide.com.
Branscome Finishes Tunnel Paving Project in Record Time
By Chuck MacDonald
CEG CORRESPONDENT
Virginia’s Hampton Roads metro area consists of Newport News, Chesapeake, Virginia Beach and surrounding areas, with a metro population of 1.6 million people.
The region embraces significant water access to the Atlantic Ocean and straddles the James, Nansemond and Elizabeth rivers. The Hampton Roads area is home to the largest U.S. Naval Base, a regional Coast Guard command and the Port of Virginia.
All these activities and the area’s multiple shipyards generate a large and diverse volume of maritime traffic. These waters carry aircraft carriers to kayakers and just about everything in between.
Vehicle traffic between these cities, bases and beaches is complex. It requires bridges, trestles, man-made islands and tunnels underneath the water to make it all work. The tunnels enable the large Navy vessels access to the ocean without being impeded by bridges.
The Monitor-Merrimac Memorial Bridge-Tunnel (MMMBT), the Hampton Roads Bridge-Tunnel (HRBT) and the James River Bridge provide a critical transportation link for the region. If trouble occurs on any of the three links, the other two strain to sustain the traffic flow to avoid gridlock from happening. The local infrastructure also includes the Downtown Tunnel in Norfolk, Midtown Tunnel in Portsmouth and Chesapeake Bay BridgeTunnel which goes from Virginia Beach to Maryland’s Eastern Shore.
Virginia Department of Transportation (VDOT) planners took steps to keep this vital transportation artery active by working with Branscome, a construction firm located in Williamsburg, to repave the MMMBT for the first time since it opened 28 years ago. VDOT contracted with Branscome to shut down traffic first in the southbound twolane tunnel for paving. Workers then paved the northbound tube. VDOT allowed Branscome four weekends in October 2020 to complete the job. Branscome did it in just two.
Because of the traffic requirements, including an average of at least 3,500 trucks per day, Branscome was required to work between 9 p.m., Friday and reopen to traffic by 5 a.m., Monday. VDOT also inserted an emergency provision requiring the tunnel to open up a lane with just 30 minutes’ notice, if needed.
On Sunday night around 11 p.m. during the first weekend of paving, the emergency provision became necessary.
“Branscome was finishing the southbound tunnel entrance when we received a call about a multi-vehicle crash and at least one of the vehicles was on fire in the HRBT,” said John Jacobs, district construction engineer, Hampton Roads District. “Our regional operations director requested that the MMBT be opened immediately because we now had two of the three Peninsula to Southside river crossings blocked. Branscome quickly demobilized and got a lane opened to the traveling public.”
Branscome immediately rerouted its empty dump trucks onto the opposite lane of the tunnel, exiting the lane on a ramp before the barrier closing the road to the public. This contingency plan enabled the paving operation to continue, although at a reduced rate, until the accidents in the other tunnel were cleared.
The completed project, approximately 1 mi. in each direction, required milling the top 2 in. of deteriorated asphalt and replacing it with fresh asphalt produced at Branscome’s asphalt plant located just over one mile from the project.
VDOT paid Branscome $1.5 million for the completed job.
The mix design allowed 15 percent of the road to be recycled materials. Workers used approximately 4,000 tons of asphalt for the project.
The job required workers to contend with numerous obstacles. In addition to working in the tight confines of a tunnel, which restricted the flow of the construction, Branscome workers had to work around manholes, curbs and iron stormwater drains without causing damage.
The tunnel’s road surface was 100 ft. below the water at its deepest point, allowing massive ships to pass overhead. Being that far underwater meant that stormwater drains were critical and could not be damaged.
These challenges were different from a typical interstate paving project.
“The contractor covered the stormwater drains with steel plates during asphalt milling removal and asphalt placement operations,” said Lance Eller, VDOT’s construction manager of Hampton Roads District. “A vacuum truck was available to clean all storm drains after asphalt placement and to ensure debris removal. During removal operations, the contractor utilized jackhammers, skid steers with milling head attachments and pickaxes to ensure the asphalt was removed as needed. During placement operations, asphalt was feathered down with shovels and rakes to ensure proper drainage in all areas.”
Despite the painstaking manual labor, Branscome workers completed paving on the first weekend seven hours early and the second weekend 18 hours early. This enabled VDOT to shut down early the extensive detour some drivers had to take over the James River Bridge or through the Hampton Bridge-Tunnel. The Branscome team also balanced their work amid COVID restrictions. Workers had little problem maintaining social distancing for much of the work. But crucial meetings usually held onsite transferred to virtual meetings to minimize exposure. This was especially important since an outbreak could have imperiled the team’s tight deadlines to finish paving and return the tunnel to normal traffic. Masks, sanitizing stations and wipes were used as needed during the project operations. Naturally, projects of this complexity require cooperation between trucking, asphalt plant operations and subcontractors, which included Richmond Traffic Control, McGowan Group and Commercial Power Sweeping.
“I believe the planning process and teamwork were key reasons the project was so successful,” said Sidney Hazelwood, project manager of Branscome. “We had buy-in from all team members and subcontractors. We had a solid plan that everyone understood, and we were able to execute that plan flawlessly both weekends.”
With traffic now back to normal in the tunnel, the VDOT and Branscome team saw the teamwork pay off.
“Frankly, I was surprised that the project could be completed in only two weekends,” said Eller. “I was also impressed by the quality of the work achieved by Branscome and the great communication between the two teams. It was a once in a career project.” CEG
The first lane of the night paving project in the Monitor-Merrimac Memorial Bridge-Tunnel is completed.
Page 30 • June 6, 2021 • www.constructionequipmentguide.com •Paving Section • Construction Equipment Guide Updates to Cat Cold Planers Ease Operation, Lower Costs
New product updates to the versatile and productive Cat PM620, PM622, PM820, PM822 and PM825 half-lane cold planers include numerous improvements based on customer feedback to ease operation and lower owning and operating costs.
Five years ago, Caterpillar brought a fresh line-up of cold planers to the market and have been continuously working on improvements to the product line ever since. The 2021 product release marks the third update to these models since they were first introduced.
The 630 hp (470 kW) PM620 and PM622 are powered by the well-known Cat C18 engine. The heavier and more powerful PM820, PM822 and PM825 are powered by the same C18 engine with a twin-turbo setup to deliver 800.6 hp (597 kW), up to 27 percent more power than the PM620 and PM622.
The five models meet U.S. EPA Tier IV Final, EU Stage V and Korea Tier 4 Final emissions standards and are optimized to reduce fuel burn with a highcapacity cooling system that keeps the engine at ideal temperatures for optimal fuel efficiency and lower emissions.
Redesigned Lighting Options Illuminate Job Sites
New expanded LED lighting enhances nighttime and low-light operation. The new wide-dispersion LED work lights come standard and provide an improved, well-lit work area for ground crew. LED perimeter lights also can be added to further illuminate the rotor chamber, cutting path and work areas around the machine for increased visibility.
New entry/exit lighting provides illumination to the ladder and operator platform when the machine is off. The forward-folding canopy option now features dimmable LED strip lights mounted to the underside of the canopy to further improve visibility on the operator platform. When the canopy is lowered, the lights continue to illuminate the intuitive, operator-friendly controls.
Integrated Technology, Efficient Performance
The integrated Cat GRADE with Grade and Slope system takes the guesswork out of producing accurate and repeatable cutting results and includes automated features like obstacle jump and programmable cut transitions to aid in milling precision. Cat cold planers also can be enhanced with full 3D milling operation.
The robust cutting system is designed to withstand the toughest applications and built to last with heavy steel construction and reinforced alloys to resist abrasion. Available in a wide variety of spacings, Cat System K rotors are durable and deliver high-performance with efficient material flow and an excellent cutting pattern. Kicker paddles are reversible for extended life, and the tapered dual retention toolholder design eliminates the need for retaining bolts, pins, or setscrews, reducing replacement time by up to 50, according to the manufacturer.
A reliable track undercarriage system with well-engineered track geometry provides high tractive effort and better load distribu-
tion when milling deep cuts or through hard materials. High-capacity conveyors provide efficient removal of milled material with outstanding discharge control. The belt also reverses for faster clean-up, while magnetic vinyl covers provide quick access to inspect the rollers for wear. Optional dust ventilation and spray bar systems maximize dust removal.
Improved Serviceability
Longer lasting conveyor flashing, improved rotor drive access, corded pendant for the rotor turning device and an added wear shoe for the inboard ski are just a handful of the many improvements included in this product update. Cat milling machines are designed with long maintenance intervals, large service doors, and power hood for walk-in access to critical components and systems. Track pads are easy to replace, while track chains and other undercarriage components are maintenance-free up to 4,000 hours. When time to replace high wear components, Cat dealers provide specialized support with repair kits, convenient parts availability, and service options for both the machine and the engine.
For more information, visit www.cat.com.
