顺层高边坡开挖松动区的数值模拟研究

Study on the Disturbed Zone of A Cut Bedding High Rock Slope by Numerical Simulation

开挖顺层岩石高边坡,往往需要进行预加固,因而合理确定坡体开挖松动区范围就成为核心问题。根据坡体开挖后的应力和位移状态,给出开挖松动区的明确定义,即变形已经超出弹性变形的范围,出现塑性破坏的区域。介绍确定高边坡开挖松动区的数值分析方法。采用合理的计算模型,利用三维显式有限差分数值分析软件FLAC3D,对重庆万梁高速公路沿线某顺层高边坡分级开挖进行数值模拟,根据开挖后坡体塑性区的分布和变化对开挖松动区进行了分析。通过对该顺层高边坡失稳实例的分析,表明该分析坡体开挖松动区的方法是可行和合理的。

To cut a bedding high rock slope, usually it is necessary to take some strengthening measures in advance. How to determine the range of the disturbed zone properly becomes a core problem. Following the stress condition and displacement condition of a cut slope, the disturbed zone is defined exactly as the Zone which deforms beyond the regime of elastic deformation and is subjected to plastic yield. A method for analyzing the disturbed zone by numerical simulation is provided. Adopting the proper constitutive calculation model, the program FLAC3D based on the explicit finite difference method is used to simulate the excavation process by the simplified geological model of High Slope K46 on the Wanzhou-Liangping Expressway, then the disurbed zone is studied according to the development and variation of the plastic zone. It shows that the results of simulation analysis agree well with the fact and the analysis method of the disturbed zone is feasible and reasonable .