Evaluation of prediction methods for lateral deformation of GRS walls and abutments

Geosynthetic reinforced soil (GRS) walls and abutments are increasingly used to support transportation infrastructure. A pressing question in their response is the amount of horizontal deflection expected under service loads. This paper presents an evaluation of six methods for predicting the lateral deformation of GRS walls and abutments, namely the FHWA, Geoservice, CTI, Jewell-Milligan, Wu, and Adams methods. Field and laboratory performances of 17 GRS walls and abutments are compared with the predicted results from the six methods. A statistical analysis is then used to evaluate the conservativeness, accuracy, and reliability of these methods in predicting the maximum lateral deformation of GRS walls. The Adams method is the most accurate method for predicting the maximum lateral deformation if the amount of vertical deformation is reasonably known. Among the Geoservice, Jewell-Milligan, and Wu methods, which have the ability to predict the lateral deformation of GRS walls at various elevations where reinforcements are located, the Wu method is the most accurate and reliable method for predicting the lateral deformation of GRS walls.