Signature Stone LLC

Scope Of Work

When it snows in Vail, Colorado, it’s a skier’s dream – but for drivers, especially trucks maneuvering steep mountain roads, it can be treacherous. To make things safer, the Colorado Department of Transportation (CDOT) wanted to widen I-70 at both sides of mountain pass locations to allow trucks to pull off and safely chain-up their wheels.

To widen the road, they needed a retaining wall separating the main road and the adjacent frontage road. However, there wasn’t enough space between the two to install a small block retaining wall due to the required length of geogrid.

Aesthetics were also very important to the scenic town of Vail. Specifically, they did not want the light poles set in front of, or behind the wall, so they had to find a way to make them a part of the wall.

“A unique design challenge was integrating the long arm light pole columns with the wall alignment in limited space,” noted Sean Chiang, Ph.D., PE of Ground Engineering Consultants. “The wall had to be interrupted at every light pole base.”

Finally, it was critical to complete the project before the winter ski season.

The Solution

HDR, Inc. was the overall design engineer of the project. They were able to come up with a design using Redi-Rock that was able to support heavy loads and incorporate the light pole bases into the wall.

Chiang explained the solution like this: “The retaining wall was required to support heavy truck loads, resist potential guardrail impact, and accommodate pavement sections and a curb/gutter behind the wall,” he said. “The Redi-Rock PC System with freestanding blocks at the top course was the best option for all these requirements.”

The Redi-Rock PC System for Mechanically Stabilized Earth (MSE) walls combines strength and beauty, making it the perfect solution for this project. The geogrid reinforcement strips wrap through each block, eliminating the chance of connection failures.

“The Redi-Rock Positive Connection (PC) was chosen because the system doesn’t require long lengths of grid due to the weight of the blocks. That allowed it to fit within the area between I-70 and the frontage road,” explained Seth Clark, Business Development/Partner of local Redi-Rock manufacturer Signature Stone. “The PC System also met the stringent Load and Resistance Factor Design (LRFD) and American  of State Highway and Transportation Officials (AASHTO) requirements.”