An aging culvert in Durham, North Carolina was in dire need of structural repair, and URETEK MA’s High-Density Polyurethane Resin, and patented Deep Injection process was utilized as the method of stabilization. The City of Durham estimated the culvert was originally built in the early 1930s, but there are no records from original construction. The culvert suffered from issues associated with original construction and age, as well as from the impact of a large tree growing into the side of the structure. The walls and floor of the culvert were washing away, and wing walls were needed. URETEK MA worked with the city as a Design-Build contractor, as well as with subcontractors, NBEs, and WNBEs to create an affordable and minimally disruptive long-term solution.
By injecting HDPR around, and underneath the culvert, URETEK MA was able to densify and stabilize the surrounding soils. This immediate improvement to the quality of surrounding soil made further repair possible. Throughout this process both a bypass pump and cofferdam were utilized to control the water levels of the creek. While URETEK MA’s HDPR is hydroinsensitive, general repair did call for a dry work environment. URETEK MA worked with a restoration team to install rebar and epoxy, as well as seal cracks throughout the culvert. A cast in place concrete floor was constructed, and shotcrete was used to make both upstream, and downstream wing walls.
The combined repairs ran several weeks, and saved the city millions. The repair was environmentally friendly, and was not inconvenient to the surrounding residents. The alternative, which involved replacing the culvert, would have taken months of construction- and would have run the city several million dollars. Utilizing HDPR to stabilize the original structure, allowed for a full repair and restoration of the culvert. This repair minimized the impact on the environment, the residents, and the city as a whole.