Damage in granite under heating/cooling cycles and water freeze–thaw condition

Abstract

In most engineering structures with rock materials, temperature variation, water content and fluid permeability are primarily responsible for rock deterioration. They affect the microstructural properties of the rock by inducing new microcracks and mineralogical changes in the material. In addition, microstructural changes, especially microcracks development in the rock, affect its physical and mechanical properties. The physicomechanical properties of the rocks are essential when assessing their suitability for use as dimension stone, as well as their durability. In crystalline rocks, such as granite, even a small temperature variation causes thermal cracking. This is because high thermal stresses arising from differential thermal expansion between mineral grains produce new microcracks or open cracks that are already in existence [1,2]. These new micro-discontinuities, together with those already exist, constitute the main fluid permeation pathway in this type of rocks because the matrix porosity is poorly developed [3]. The fluid reacts with the rock at the rock–water interface, producing mineral dissolution and/ or precipitation reactions [4]. In silicate rocks, water reacts with silicate to break the bond, inducing profound chemical effects on the physical properties and the microstructure of the rock [5]. Any mineralogical change implies a modification of the geometry of the porous network, which enhances or reduces fluid flow in the rock. For example, the deposition of secondary minerals within a fracture or a crack wall can completely or partially seal this