Investigation of global stress-strain and interaction behavior of geogrid reinforced soil with biaxial compression tests

Abstract

After decades of application of the modern composite material geogrid reinforced soil, its design can still beimproved. With the development of increasingly strong techniques of numerical modeling (finite element or finite difference methods), attention is refocusing on correct modeling of the complex interaction behavior between the two materials as its description with common interface models has been unsatisfactory so far. A sophisticated large-scale biaxial compression test device at RWTH Aachen University with a transparent side wall has been developed, allowing the quantitative investigation of the soil-geogrid interaction mechanisms. In this study, a special test series of specimens, reinforced with geogrid samples with different numbers of longitudinal and transverse tensile members, is used to quantify the effects of the load transfer mechanisms on the global stress-strain behavior. Additionally, an interaction model, recently developed for pullout situations that explicitly takes into account the separate load transfer mechanisms, is transferred to the plane strain conditions of biaxial compression tests. First results, presented in this paper, are promising and show that the model is capable of describing the complex interaction between geogrid and soil.