Experimental Investigation of the Static and Dynamic Compression Characteristics of Limestone Based on Its Initial Damage

Abstract

In the current work a new equation for initial damage assessment of limestone based on plane strain theory is proposed. Detailed investigations of the static and dynamic characteristics of limestone with different initial damage degree, using longitudinal wave speed, and static-dynamic compression tests are performed. This study investigated the static and dynamic characteristics of limestone with different initial damage degree, using longitudinal wave speed, and static-dynamic compression tests. Experimental results show that the degree of initial damage decreases with increasing longitudinal wave speed, which reaches the minimum when the longitudinal wave speed is approximately 6000 m/s, and the smaller the longitudinal wave velocity, the greater the degree of initial damage. The static and dynamic compressive strengths of limestone increase with the longitudinal wave velocity and strain rate, but the elastic modulus and Poisson’s ratio do not change significantly. Finally, based on the experimental results, the definitions of damage threshold value and strain softening are proposed, which further verify the influence of strain rate and initial damage on rock compression characteristics. The present study sheds light on the importance of initial damage for the mechanical state of rock in underground engineering.

Numerical simulation of size effect of defective rock under compression condition

“…They found that the initial damage has a significant effect on the creep behavior of rock and proposed a new nonlinear creep damage model to predict the creep behavior of sandstone under different initial damage states. Wang Yongqian et al 29 studied the static and dynamic characteristics of limestone with different initial damage degrees by using longitudinal wave velocity and static-dynamic compression test. They found that strain rate and initial damage have obvious influence on rock compression characteristics.…”