Energy dissipation and dynamic behaviour of clay under cyclic loading

Abstract

A laboratory study has been conducted to investigate the dynamic behaviour of Champlain Sea clay from two locations in the Ottawa River valley region. The test program includes cyclic triaxial tests and resonant-column tests. The soil samples were consolidated at a range of pressures before the dynamic shear in order to cover the dynamic behaviour under both the overconsolidated and the normally consolidated states. An energy concept is introduced to interpret the test results. Mathematical relationships have been established for describing the various aspects of dynamic behaviour. These aspects include excess pore pressure, dynamic strength, dynamic shear modulus, and plastic strain. The study shows that the energy concept provides a promising way to analyze dynamic soil behaviour. Key words : energy, dynamic behaviour, clay, cyclic test, earthquake, excess pore pressure, shear modulus, strength.