Study of Mechanical Properties of Soil-Cement Mixture for a Cutoff Wall

Abstract

A series of triaxial compression tests on soil-cement mixture samples has been made in order to investigate its mechanical properties. The test results show that as the confining pressure increases, the strength and the strain at peak stress of this soil-cement mixture increase drastically and the initial modulus changes very little. The failure mode is a plastic-shearing one imposed by the confining pressure. These results are different from the previous ones for a soil-cement mixture being brittle and of low strength obtained based on unconfined compression tests, where the condition does not satisfy the actual in situ stress condition for the cutoff wall. The study suggested an important idea of using a soil-cement mixture instead of common concrete to construct a deep cutoff wall under high earth-rockfill dams. This has been proved by the stress-displacement analysis by FEM for a high earth-rockfill dam with a cutoff wall in deep alluvium.