Tensile Strength of Rock Under Elevated Temperatures

摘要

Rock strength affects the behaviour of rocks differently under different conditions such as temperature, time, pressure, presence of fluids, rock mass characteristics and stress history of rock in a natural environment. It is not always easy to replicate such conditions of undisturbed rock in a laboratory scale. Hence, it is imperative to study the rock behaviour with respect to every such condition which the rock experiences since its time of formation. Temperature is one of the key parameters which influence the rock throughout its history, ranging from the conditions of formation, experience of depth (loading/unloading) or deformational and metamor-phic history. Also, increase in rock temperature; say due to the thermal stress changes like disposal of spent nuclear fuels affects the strength of the surrounding rock. In this work, the effects of temperature on the tensile strength of rock have been studied. The results obtained were interesting as the strength of rock is found to increase considerably up to a particular temperature after which it starts falling by as much as 70% around 250°C.