절리 암반터널의 불연속체해석과 연속체해석에 관한 고찰

Numerical methods to estimate behaviors of jointed rock mass can be roughly divided into two methods : continuous and discontinuous model. Generally, distinct element method(DEM) is applied in discontinuous model, and finite element method(FEM) or finite difference method(FDM) is utilized in continuum model. To predict a behavior of discontinuous model by DEM, it is essential to understand characteristics of joints developed in rock mass through field tests. However, results of field tests can not provide full information about rock mass because field tests are conducted in limited area. In this paper, discontinuous analysis by UDEC and continuous analysis by FLAC are utilized to estimate a behavior of a tunnel in jointed rock mass. For including discontinuous analysis in continuous analysis, joints in rock mass is considered by reducing rock mass properties obtained by RMR and decreasing shear strength of rock mass. By comparing and revising two analysis results, analysis results similar with practical behavior of a tunnel can be induced and appropriate support system is decided.