Experimental study on biaxial dynamical compressive test and PFC2D numerical simulation of artificial rock sample with single joint

Abstract

Dynamic biaxial compression tests and Particle Flow Code numerical simulations of the cement mortar specimens with a single joint were carried out to study the mechanical properties and crack evolution of artificial rock samples with a single joint. The effects of lateral stress 𝜎 2 , loading rate 𝑉 , the dip angle 𝛽 (between the vertical loading direction and the joint) on the biaxial compressive strength 𝜎 𝑏 , and the evolution law of crack were investigated. Test results showed that; (1) when both the dip angle 𝛽 and the loading rate 𝑉 remained unchanged, the biaxial compressive strength 𝜎 𝑏 increased with the increase in the lateral stress 𝜎 2 , while 𝜎 2 had no obvious effect on the crack evolution law;(2) when both the dip angle 𝛽 and the lateral stress 𝜎 2 were kept unchanged, the loading rate 𝑉 had an insignificant effect on the biaxial compressive strength 𝜎 𝑏 and the crack evolution law; (3) when both the lateral stress 𝜎 2 and the loading rate 𝑉 were constant, the biaxial compressive strength 𝜎 𝑏 decreased first and then increased with the increase in the dip angle 𝛽; however, the dip angle 𝛽 did not significantly affect the crack evolution law. The conclusions obtained in this paper are presented for the first time.