The Maryland State Highway Administration (SHA) was forced to detour traffic after a pipe running under the roadway collapsed after heavy rains. Given the unforeseen circumstances, the Maryland SHA required an emergency replacement of the collapsed culvert running under the off ramp from State Highway 50 onto Garden City Drive as quickly as possible.
During the excavation of the existing culvert, the contractor, Covington Machine & Welding, Inc., discovered an electrical duct bank encased in concrete that was lower than previously thought. Due to the location of this conduit, they could not utilize the structural plate culvert that was originally specified as the replacement structure. As the location was directly under an extremely busy roadway, they needed to find an alternate solution that would work structurally, hydraulically and obtain the material quickly.
Contech Engineered Solutions was able to provide a DuroMaxx® steel reinforced polyethylene (SRPE) drainage solution that met the project requirements – both structurally and hydraulically. The unique DuroMaxx profile with steel reinforced ribs would provide the necessary structural strength while the smooth interior wall would meet the hydraulic requirements. Two runs of 156 LF were installed including both 120-inch and 48-inch diameter DuroMaxx pipe.
Considering that the emergency repair necessitated a quick turnaround to avoid further traffic delays and frustrations, the Contech manufacturing team worked quickly and started delivering pipe within three business days from receipt of order. Contech was also able to supply their field welding services for installing the HDPE coupler to the joints. Utilizing the field welding option for the welded coupler (WC) joints for the 120-inch diameter DuroMaxx pipe not only provided a 30 PSI, watertight connection but allowed the contractor to backfill the pipe prior to welding.
It took approximately one week to install the pipe and another week for field welding services. The overall project was a success as the contractor was able to install the DuroMaxx pipe in a timely manner and re-open the roadway.
Robert Dailey from Covington & Welding Inc. commented, "The ability to get 120" pipe so quickly was a tremendous help in getting the road back opened. The ability to install a product of that diameter in longer lengths contributed greatly to our production schedule."