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

To study the grouting reinforcement mechanism in jointed rock slope, first, the theoretical deduction was done to calculate the critical length of slipping if the slope angle is larger than that of joint inclination; Second, the numerical calculation model was founded by FLAG^3D, so as to find the stress and deformation responses of rock mass in the state before and after grouting, the analysis results show that the range between the boundary 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, and large deformations along the joint plane are controlled; the dynamic displacement can re- flect the deformation response of slope during excavation in the state before and after grouting, as well as the shear location of potential slip plane. After grouting, the dynamic displacement 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, are improved; the stress field becomes uniform. Tensile area reduces gradually; whole stability of the slope and its ability to resist tensile and shear stress are improved greatly.

充填水泥浆岩石节理峰值剪切强度模型

通过理论分析和室内直剪试验,对充填水泥浆岩石节理的峰值剪切强度模型进行研究。首先,建立考虑三维形貌特征的充填水泥浆岩石节理峰值剪切强度模型;其次,采用建立的强度模型计算充填水泥浆节理的峰值剪切强度并与直剪试验结果进行对比;最后,对模型计算值和试验值之间的误差进行分析。研究结果表明,建立的充填水泥浆节理峰值剪切强度模型描述了三维形貌、充填度、节理岩壁与水泥结石强度比对充填节理峰值剪切强度的影响;模型计算的充填水泥浆节理峰值剪切强度与试验结果吻合较好,验证了模型的合理性;模型预测的峰值剪切强度与试验值之间存在一定误差,造成误差的主要原因包括模型本身缺陷和试件制备导致的节理黏结缺陷。充填水泥浆岩石节理峰值剪切强度模型的建立具有一定的理论意义,为进一步建立充填水泥浆节理本构理论奠定了基础。