基于不稳定块体失效概率的开挖面稳定性分析

Stability Analysis of Excavation Surface Based on Failure Probability of Unstable Block

基于团队开发的空间网络模型,利用一般块体理论进行块体分析,可以得到开挖面上不稳定块体的安全系数、体积及其棱长.利用棱长和迹长推出块体生成概率,并与安全系数一起求出块体失效概率.然后将失效概率大于失效标准的块体定为失效块体,并提出将开挖面上失效块体体积占所有不稳定块体体积的比例作为评价开挖面稳定性的指标,从而提出基于不稳定块体失效概率的开挖面稳定性分析方法.基于一个实际边坡工程,利用上述方法对其进行开挖面稳定性分析.

Based on the spatial network model developed by our team,the general theory of block was used for block analysis,the safety factor,the volume and the edge length of unstable blocks in the excavation surface were obtained. The block generation probability can be first determined by the edge length and the trace length,then the block failure probability was calculated by the block generation probability and the safety factor. The failure block was identified when the failure probability of block is greater than the standard value. The ratio of the failure volume of rock blocks to the unstable volume of rock blocks was used as an evaluation index on the excavation surface stability,and a stability analysis method of the excavation surface was proposed on the basis of the unstable blocks failure probability. An example was given to evaluate the stability of the excavation surface based on this method.