PITTSBURGH, PA – Nicholson Construction recently completed emergency repair work to an unstable pier supporting a bridge on INDOT’s Interstate 65. These repairs enabled a 37-mile section of the highway’s northbound lanes to be reopened after a four-week closure.
The highway was in the process of being rehabilitated and widened when the pier was damaged by steel piles driven into the water tight ground below it. The pier began to settle and eventually rotated ten inches.
Nicholson developed a design-build solution that used micropiles to transfer the loads to more stable soils and low-mobility grouting to fill voids and densify the upper subsurface layer.
“The natural artesian groundwater conditions were instrumental in causing the problem and posed the biggest challenge in developing the fix,” said Rick Deschamps, Vice President of Engineering. “The design-build approach developed was geared towards minimizing the risk of additional damage to the pier, while providing a safe and timely solution.”
Because of the emergency nature of the job, the Nicholson team had to mobilize to the site quickly, install test piles and install the piles within three days to fix the settlement issues. In addition, the coring of the footing and low mobility grouting below the pier foundation were also completed.
“The use of micropiles allowed a deep foundation to be installed within the artesian conditions of the site and overhead constraints of the existing bridge,” said Aaron Evans, Area Manager for Nicholson’s Chicago Office. “The closure of I-65 was obviously a major issue, and we are pleased to have been a part of developing the solution to reopen the interstate.”
Work for this phase of the I-65 project is scheduled to be completed in Spring 2016.
About Nicholson Construction Company
Nicholson is a versatile geotechnical contractor specializing in deep foundations, earth retention and ground treatment. As the North American subsidiary of Soletanche Bachy, one of the world’s leading geotechnical contractors, we are part of a global network of geotechnical resources and expertise. We work in a wide range of industries and environments, from power plants and dams, to bridges and skyscrapers. Headquartered in Pittsburgh, Nicholson has offices around the country to address each region’s unique geotechnical construction needs.