Two full-scale loading experiments of geosynthetic-reinforced soil (GRS) abutment wall

Abstract

Two full-scale segmental facing Geosynthetic-Reinforced Soil (GRS) abutment walls, referred to as "the NCHRP test abutments", were constructed and load-tested at the Turner-Fairbank Highway Research Center in McLean, Virginia. The two experiments were conducted to (1) examine the behavior of segmental facing GRS abutment walls under increasing vertical loads on a bridge sill, and (2) furnish a set of well-defined data for verification of analytical models. This paper describes the two experiments and the measured and observed behavior due to the load applications. The behavior of the test walls were discussed and compared with existing performance criteria that were developed based on experience with real bridges. The comparisons were made in terms of maximum sill settlement, maximum angular distortion, and maximum lateral wall movement. In addition, the safety factors and failure loads of the test walls were evaluated by the prevailing design method. The predicted failure loads obtained from the prevailing design method, even with all safety factors and strength reduction factors being set equal to one, were found to be much lower than the measured values, suggesting that the prevailing design method is likely to be overly conservative.