Effect of Strain Rate on Compressive Behavior and Modeling of Cement and Asphalt Mortar

Abstract

The compressive behavior of cement and asphalt mortar (CA mortar, including Types I and II CA mortar, namely CAI and CAII) under strain rates ranging from 1−5/s to 1−2/s was experimentally investigated using an electrohydraulic servo tester. The strain rate effects on the failure pattern, compressive strength, elastic modulus, and peak strain were studied. The results showed that the compressive strength and elastic modulus of CA mortar increased with increasing strain rate. The peak strain of CAI increased with the strain rate, whereas the peak strain of CAII showed a reverse tendency. At the same strain rate, the compressive strength, elastic modulus, and peak strain of CAI were smaller than those of CAII, but the strain rate sensitivity of the compressive behavior of CAI was stronger than that of CAII. A constitutive model involving the strain rate for CA mortar is proposed based on the theory of thermodynamics and damage mechanics.