Membrane Effects in Biaxial Compression Tests

Abstract

The effects of the confining membrane in laboratory tests on soil specimens have been the subject of numerous experimental, analytical, and numerical studies over the past half-century. This technical note expands the existing knowledge base by presenting a methodology and the associated results from an experimental study that has quantified the effect of the confining membrane in biaxial shear tests conducted on medium sand. The applicability of the method of biaxial tests on clay specimens is also presented. The results show that for both tests on sands and clays, the effect of the membrane on the shear stress on the failure plane are significant and should be accounted for in the interpretation of biaxial shear test results where localization occurs.