ABSTRACT
This chapter describes the role of numerical modelling in understanding the rock mechanics problems through back analysis and in the prediction of the rock mass response during construction. Numerical modelling has emerged as a powerful tool for stress analysis in the design of underground excavations. Several numerical techniques are available to model the rock mass as “equivalent” continuum or as discontinuum with explicit representation of the structural features. Three major ongoing projects in India are: the Sardar Sarovar Project in the state of Gujarat, the Srisailam Left Bank Hydro-Power in Andhra Pradesh and the Nathpa Jhakri Power Project in Himachal Pradesh. Rock mechanics problems were encountered during the construction of the underground power house because of the major discontinuities crossing the power house. The power house is located at a shallow depth below a sloping ground surface. The rock cover varies between 40 and 60 m along the length of the power house.
