基于极限平衡理论的滑坡抗剪强度参数反演数据表法研究

Back Analysis on Shear Strength Parameters of Landslide by Datasheet Method Based on Limit Equilibrium Theory

滑裂面抗剪强度参数c和φ值的合理选取,是滑坡安全评价和防治工程设计的关键。传统的确定性滑坡参数反演方法未能考虑岩土参数随机性和不确定性的影响,基于极限平衡理论和可靠度理论,将数据表法和传递系数法相结合,提出了一种简单实用的滑坡强度参数反演方法;该法只需一个平衡方程获得优化的抗剪强度参数反演值,可解决单一滑面强度参数的反演问题;以鲜家沟滑坡为分析模型,开展了滑裂面抗剪强度参数反演实例分析。研究结果表明,反演结果与勘测试验值符合较好,证明了方法的有效性。

How to select shear strength parameters c and φ of slip surface is the key to the stability evaluation of landslide and the prevention design. Since the traditional back analysis method for deterministic landslide parameters fails to consider the randomness and uncertainty of geotechnical parameters,this paper,on the basis of limit equilibrium theory and reliability theorem,combined datasheet method and transfer coefficient method has put forward a simple and practical back analysis method for landslide＇s strength parameters. This method only requires an equilibrium equation to get the optimized inversion values of shear strength parameters,and may solve the inversion value of strength parameters on single slip surface. Taking Xianjiagou Landslide as the model,the back analysis of shear strength parameters on slip surface was carried out. The result shows that the values of back analysis agrees with the ones from investigation and test well,and has demonstrated that this method is effective.