High-Temperature Influence on Mechanical Properties of Diorite

Excerpt

Knowledge on rock mechanical behaviors under/after high-temperature conditions is extremely important for projects such as deep geological disposal of nuclear waste (Sellin and Leupin 2013; Verma et al. 2015), hot dry rock (HDR) geothermal energy extraction (Brown et al. 2012; Gelet et al. 2012), and underground coal gasification (Burton et al. 2006; Otto and Kempka 2015), for it can provide a basis for deformation, stability, and safety analyses of the projects. High temperatures can cause thermal expansion of rock-forming minerals, thermal stresses, and chemical reactions in a rock body and thus produces micro-cracks and damages rock microstructures. As a result, rock behaviors exposed to high temperatures may be quite different from those under normal temperature conditions. It has been known that rock strength and deformation modulus generally decrease with increasing temperature, especially beyond a certain temperature (e.g., Dwivedi et al. 2008; Chen et al. 2012; Singh et al. 2015; Tian et al. 2016; Peng et al. 2016; Ding et al. 2016). Therefore, research on high-temperature rock mechanics is important and essential in both theory and practice. …