Damage Time-Dependent Characteristics and Failure Mechanism of Limestone with Different Mineral Compositions Under Acid Hydro-Chemical Solution Erosion

Abstract

Taking two types of limestone with different mineral compositions as research objects, we conducted experiments on the mass, longitudinal wave velocity, ion concentration of solution, fracture morphology, and micromorphology of two types of limestone specimens eroded by acidic hydro-chemical solution. We investigated specimens’ damage time-dependent physical properties, dissolution, structure, discussing mineral composition effects and destruction. Results show that the mass loss rate of two types of limestone specimens eroded by acidic hydro-chemical solution increases with the increase of immersion time in a power function, and the longitudinal wave velocity decreases and then fluctuates in a small range. The specimen fracture degree increases with the increase of the immersion time, and the rock micro-structure changes from dense and uniform into loose and porous. The mass, the longitudinal wave velocity, the fracturing morphology, and damage to microscopic morphology of specimens increase with the increase of solution ion concentration. The acid rock reaction rate of limestone A is lower than that of limestone B, while the hydrolysis reaction rate is higher. The mass loss rate, the longitudinal wave velocity loss rate, the ion concentration, and the damage degree of the macro-and micro-structure of limestone A are higher than that of limestone B.