LOAD TEST OF GRS BRIDGE PIER AND ABUTMENT IN DENVER, COLORADO

A geosynthetic reinforced soil (GRS) bridge abutment and two GRS bridge piers were constructed inside a 3.5-m deep pit in Denver, Colorado. The structures were constructed with a road base backfill and reinforced with layers of a woven geotextile. Dry-stacked hollow-cored concrete blocks were used as facing. One of the piers and the abutment, both 7.6 m in height, were load tested. The load was applied using concrete barriers stacked in seven layers over three steel bridge girders. A total load of 2,340 kN, corresponding to 232 kPa vertical pressure, was applied. The pier and the abutment were instrumented with metal pipes and elastic springs to monitor the vertical and lateral movement of the facing, and strain gages to monitor deformation of the reinforcement. This report describes the configuration of the structures, the material properties of the backfill and the geotextile reinforcement, the construction procedure, the loading schemes, and the instrumentation. The report also presents measured results and discussions of the measured results.