Thermally Induced Behavior of the Openings in Rock Mass Affected by High Temperatures

The temporary storage of hot water in openings excavated in rock may be worthwhile for multiple land-use applications, environmental safeguards, and energy conservation. When used for hot water storage, the rock mass around the openings will respond by coupled thermomechanical effects induced by the hot water. In this study, a submergence test of granite and sandstone at 20 and 95 degrees C was used to examine the thermal behavior of the rock mass around the openings to obtain the mechanical properties of uniaxial compressive strength and elastic modulus. A uniaxial compression creep test of the rock at high temperatures was also performed and calculations with various constants for the creep were examined. With the results obtained in this work, the temperature and stress distribution around the openings when hot water is stored was analyzed by considering the creep properties. The thermal behavior and stability of the openings were also examined. The displacement of the openings was predicted to be approximately 2% of the diameter after 1,000 days. (C) 2011 American Society of Civil Engineers.