The high geostress has important influence on deep-buried tunnels during the phases of design and construction. As the natural test project of western route of South to North water transfer project in China

the deep-buried water transfer tunnel of Yindajihuang Project faces the problems of rockburst in hard rock and plastic deformation in soft rock under high geostress. Representative physico-mechanical properties are studied out according to the survey data. ANSYS finite element analysis procedure is applied to the stability analysis of tunnel rock. The distribution characteristics of deformation

the maximum tensile the maximum

stress

possible rockburst area

plastic deformation zone and shear failure zone are studied under different conditions

gravity geostress field

full geostress field

and calculated according to linear elastic method and elastoplastic method. Analysis result is applied to Yindajihuang Project

and the importance of checking in time in the course of construction is pointed out.