Physical Properties of Sandstones After High Temperature Treatment

Excerpt

Under the influence of high temperatures below the rock melting point, rock micro-structures change significantly (Dwivedi et al. 2008), new micro-cracks are developed, and pre-existing ones extended/widened (Den’gina et al. 1994). Meanwhile, various physical and mineralogical changes take place in the rock matrix. After cooling down to room temperature, thermal-induced changes are irreversible to some extent. Hence, rock physical properties from a macroscopic point of view are temperature-history dependent as they rely on the maximum temperature experienced. Knowledge on this issue is a key factor for successful implementation of modern geotechnical engineering projects, such as nuclear waste storage (Sundberg et al. 2009), underground coal gasification (Roddy and Younger 2010), geological CO₂ storage (Rutqvist et al. 2002), geothermal heat extraction (Zhao 2000) and stability analysis of constructions in rocks after exposure to fire (Zhan and Cai 2007). …