Rock Properties and Their Effect on Thermally Induced Displacements and Stresses

Abstract

A discussion is given of the importance of material properties in the finite-element calculations for thermally induced displacements and stresses resulting from a heating experiment in an in-situ granitic rock, at Stripa, Sweden. Comparisons are made between field measurements and finite element method calculations using (i) temperature independent, (ii) temperature dependent thermal and thermomechanical properties, and (iii) in-situ and laboratory measurements for Young’s modulus. The calculations of rock displacements are influenced predominantly by the temperature dependence of the thermal expansion coefficient, whereas the dominant factor affecting predictions or rock stresses is the in-situ modulus.