Undrained Behavior of Clay Under Cyclic Shear Stresses

Abstract

The cyclic behavior of normally consolidated clays is investigated by conducting a series of cyclic simple shear tests on one-dimensionally and isotropically consolidated kaolinite samples. The response of two types of specimens are evaluated and compared based on tests performed with different cyclic shear stress amplitudes and frequencies. The cyclic stress-strain-pore pressure and cyclic shear strength properties of the clay samples are studied and a simple procedure is suggested to define cyclic yield strength. The results also indicate that there is a threshold cyclic shear stress level below which no excess pore pressure will develop. An attempt is made to develop an empirical procedure to estimate the response of a soil element subjected to cyclic shear stresses for a given number of cycles.