Three-Dimensional Finite Element Analysis of Underground Caverns

Detailed performance monitoring studies have been carried out for determining the deformations and stress distribution around underground powerhouse caverns in nonhomogeneous rock mass, using three-dimensional finite element method. The behavior of rock mass has been analyzed by elasto-plastic model. The effect of weak zones and creation of multiple caverns in the rock mass has been investigated. The deformations predicted in the surrounding area of the caverns are compared with those obtained by multi-point borehole extensometers (MPBX) measurements. It is observed that the computed deformations compare reasonably well with the MPBX measurements.