Design and Application of Simple Shear Liquefaction Box

A cyclic simple shear liquefaction box (CSSLB) was designed and manufactured to allow laboratory testing of saturated sands under cyclic or transient strain-controlled conditions. The box accommodates pore water pressure transducers, linear variable displacement transducers, and bender elements and bending disks. To induce shear strains, the box has two rotating walls connected to two translating rigid walls with a flexible sealant. When the tops of the rotating walls are fixed against translation and the base of the CSSLB, which rests on a shaking table, is excited with a displacement time history, shear strains are induced in a soil specimen. Two-dimensional numerical analyses of plan and elevation sections of the CSSLB were performed, demonstrating that the design of the box and the mechanism for shearing can induce controlled shear strains in sand specimens with minimal boundary effects. Example test results from sand specimens subjected to cyclic and earthquake shear strain time histories are presented and illustrate how well the CSSLB with its instrumentation is suited for conducting tests on relatively large soil specimens.