Effects of geotextiles on lateral pressure and deformation in highway embankments

Abstract

A procedure to lower the lateral loading acting on the back of a highway abutment wall utilizing geotextiles is described. A gap is formed between the wall and the geotextile reinforced backfill using either corrugated cardboard (which is wetted after construction) or removable plywood forms. This allows the backfill to deform and go into the active state. The fabric sustains the resulting tensile forces, essentially forming a free-standing fabric wall behind the abutment. Laboratory testing indicates that less than 25 mm lateral movement is required to reduce lateral loads by 90 percent. Four reinforcement schemes were compared on two Interstate bridges. The fills were instrumented with inclinometers, Sondex tubing and pressure cells. The results indicate that an initial gap reduces the lateral load to essentially zero and settlements were no greater with the voided system than that experienced by a nonvoided fill