基于施工监测和三维模拟的临危边坡锚固方案研究

Anchorage scheme against imminent failure of slope based on on-site monitoring and 3D numerical modeling

依据实际工程边坡案例,研究利用施工监测资料联合边坡稳定分析三维数值模拟确定临危边坡锚固方案的方法。研究表明,根据连续的监测资料可确定边坡内部剪切位移带的位置、发生区间和开始时间,据此可推测边坡潜在滑移面的位置和形状;边坡稳定分析有限元法三维模拟可以考虑坡体断面形态变化对坡体稳定和变形的影响,计算结果更具有合理性;以三维数值计算得到的坡体外部变形拟合实测变形和滑动面,依据临危边坡所处的极限平衡条件,可以确定坡体当前状态的等效力学参数;根据等效力学参数,通过三维模拟可以确定坡体最终形态下的潜在滑动面形状和位置,从而合理地确定加固锚索的长度和密度;工程运行情况表明,由此确定的加固方案是可靠的。

In this paper, an anchorage scheme against the imminent failure of slope in practice has been proposed by considering on-site monitoring data and 3D numerical modeling. From the results, the position, time interval and initial time of internal shear slip plane are observed, according to the continuous monitoring data of the slope. Therefore, the position and shape of a potential slide plane can be predicted. Since the influence of the section morphology on slope stability and deformation is considered in this study, the results obtained by 3D numerical modeling are more reasonable. By fitting the external deformation and sliding surface with the numerical modeling and the measured data, the equivalent mechanical parameters of slope in any state are determined, according to the limit equilibrium condition of the imminent failure slope. From the equivalent mechanical parameters, the ultimate shape and position of the potential sliding surface are obtained by 3D simulation. The length and density of the reinforcement anchor cable can be further decided properly. The performance of this case study demonstrates that the proposed reinforcement scheme is reliable.