SHPB tests and dynamic constitutive model of artificial frozen sandy clay under confining pressure and temperature state

摘要

The dynamic stress-strain curves of frozen sandy clay are obtained with the spilt Hopldnson pressure bar (SHPB) under different confining pressures (i.e., 0.5,1.0 and 1.5 MPa) at the freezing temperature of -5 degrees C and -15 degrees C with the strain rate from 160 s(-1) to 265 s(-1). The experimental results show that the frozen sandy clay is a rate dependent and temperature sensitive and confining pressure sensitive material and its dynamic peak stress increases with the increase of the strain rate and the confining pressure and the decrease of the freezing temperature. A dynamic constitutive model is proposed based on the test results. The theoretical and the experimental results are very close and the given dynamic constitutive model is feasible. The effect of confining pressure, strain rate and freezing temperature on the dynamic mechanical behavior of frozen sandy clay are well considered in the model. (C) 2017 Elsevier B.V. All rights reserved.