EFFECT OF TUNNEL DEPTH ON MODULUS OF DEFORMATION OF ROCK MASS

Deformability of rock mass significantly influences its behaviour and is, therefore, an important consideration for the design of undergroun d openings. The modulus of deformation of rock mass is, however, norma lly obtained from expensive and time-consuming uniaxial jacking tests, whose results often have a large scatter. An empirical correlation ha s, therefore, been proposed for a quick and inexpensive preliminary es timation of the modulus of deformation of rock mass on the basis of fi eld instrumentation carried out in tunnels in India.