Influence of Chemical Corrosion on Dynamic Fracturing Mechanical Behavior of Marbles

Abstract

To investigate the influences of the chemical corrosion on the dynamic fracture mechanical properties and failure characteristics of marble, the dynamic fracture test for the notched semicircular bend (NSCB) marble specimens with different degrees of corrosion damage was conducted using a split Hopkinson pressure bar. The results show that both the porosity and corrosion damage variable Dc characterized by porosity increase as corrosion time T increases. The dynamic fracture toughness decreases linearly from 5.22 to 2.15 MPa m1/2 as Dc increases from 0 to 4.42%. This is because the corrosion damage done to interior structure leads to a reduction of cohesion and internal friction angle inside the specimen. In the Dc range of 0–4.42%, the fractal dimension of the main crack propagation path increases from 1.47 to 1.59, by an increase rate of 8.16%. Both the joint roughness coefficient and the actual area of the fracture surface increase as Dc increases. Due to the degradation of the connected force between the rock particles inside the specimen, there is an obvious decrease in the fracture energy per unit fracture surface from 0.94 to 0.38 J cm−2, with a decrease rate of 59.39%. With T increases, the contents of CaO, MgO, and Al2O3 in specimen increase, indicating that the degree of corrosion damage increases.