Macroscopic effects of rock slopes before and after grouting of joint planes

摘要

Studies on slope reinforcement methods are important for geotechnical engineering. All ofthe reinforcement methods can be divided into two groups,the passive reinforcement methods and the activereinforcement method. Grouting is an active reinforcement method. It is to inject a cement grout mixture intothe rock mass to reduce the permeability of the rock mass and improve the mechanical properties of the rockmass itself. In order to find differences of parameters between the rock mass before and after grouting,thecomparative experiments of direct shear were done that indicates that the shear strength and shear stiffness ofrock samples are improved greatly after grouting. However,no the whole slope must be grouted. The effectivegrouting areas (EGA) can be defined by relative calculations. The three dimensional explicit finite differencecode,FLAC3D,was adopted to study the differences of mechanical properties of the rock mass before and aftergrouting. Comparative analysis shows that stress field and displacement field of the rock mass become moresymmetrical and continuous after grouting. The tensile stress area reduces and the displacement bifurcation nearjoint planes vanishes,both are good to the stability of slope.