Effective grouting area of jointed slope and stress deformation responses by numerical analysis with FLAC^(3D)

摘要

To study the grouting reinforcement mechanism in jointed rock slope, first, thetheoretical deduction was done to calculate the critical length of slipping if the slope angleis larger than that of joint inclination; Second, the numerical calculation model wasfounded by FLAC^3D, so as to find the stress and deformation responses of rock mass inthe state before and after grouting, the analysis results show that the range between theboundary of critical slipping block and the joint plane that passes the slope toe is the effective grouting area (EGA). After excavation, large deformation occurs along the joint plane.After grouting, the displacements of rock particles become uniform and continuous, andlarge deformations along the joint plane are controlled; the dynamic displacement can reflect the deformation response of slope during excavation in the state before and aftergrouting, as well as the shear location of potential slip plane. After grouting, the dynamicdisplacement of each monitoring point reaches the peak value with very few time steps,which indicate that the parameters of the joint plane, such as strength and stiffness, areimproved; the stress field becomes uniform. Tensile area reduces gradually; whole stabilityof the slope and its ability to resist tensile and shear stress are improved greatly.