Abstract
The large displacement shear box (LDSB) allows testing of interfaces as large as 711 by 406 mm (28 by 16 in.) with maximum interface displacements of 305 mm (12 in.). This device has been used to investigate the response of a variety of interfaces, including clay-geomembrane interfaces for which large displacements are important. The most recent application of the LDSB was to study the response of several sand-to-concrete interfaces under complex loading paths. In this application, the relevant characteristics of the LDSB are its geometry, which reduces the significance of end effects, its ability to apply monotonic and cyclic loading, and its ability to apply simultaneous changes in shear and normal stresses so that complex loading paths can be followed. This paper describes the main features of the LDSB, as well as the testing procedures and results of the sand-to-concrete interface tests that were performed. A procedure for normalizing the interface shear test data is also presented. This procedure facilitates comparative evaluations of interface response to different types of loading. The test results formed the basis for development of an extended hyperbolic model for interfaces that has been implemented in finite element analyses of soil-structure interaction problems.