Comparative studies on heat and stress build up in jointed and intact granites at depth of 220 m, Bhima Basin, India

Two-dimensional simulation of heat transfer through a granite rock mass forming part of Proterozoic granites in Bhima Basin (BB) and associated groundwater flow and bulk stress distribution is carried out using structural geological features joints, fractures, etc. measured in field and laboratory evaluated mechanical, thermal and hydraulic parameters of 56 rock samples coupled with prevailing in situ stress field. The modelled rock mass (20 m x 10 m) consists of D-shaped opening at 220 m depth containing cylindrical heat source (500 Watt) and clay buffer with two sets of joints dipping at 90° and 45°. The intact rock mass under combined thermal and overburden stresses registers a maximum 19.77 MPa stress while it is 23.34 MPa in jointed rock mass due to additional stresses imposed by groundwater in the joints resulting in maximum displacement, groundwater flow and temperature of 4.46 mm, 1.93 x 10^–8 m/s and 78.21°C respectively. The present study produces database on response of BB granites to applied thermal in situ-groundwater stresses.