基于力传递的关键块体理论在地下洞室围岩支护中的应用研究

Application of key block theory based on force transfer algorithm in underground cavern rock support

地下洞室的稳定性与洞室围岩中的关键块体的稳定性密切相关,未揭露前,关键块体具有随机分布的特点。搜索并计算随机块体的安全系数对洞室围岩整体稳定性评价及围岩支护方案的选择至关重要。为准确计算关键块体的安全系数,本文将关键块体理论与力传递算法相结合,拓展了传统关键块体理论,考虑内部块体间的力传递作用,应用基于力传递算法的改进的关键块体理论分析方法对块体稳定向进行分析评价。包括典型块体的空间状态分类、不同类别块体的识别、块体间力传递过程等。以泰山抽水蓄能电站岩体地下洞室为例,对比分析了力传递前后临空面处关键块体安全性能的变化,分析评价了洞室锚杆支护系统的支护效果。

The stability of underground caverns is closely related to the stability of key blocks in the surrounding rock of the caverns.Before uncovering,the key blocks have the characteristics of random distribution.Searching and calculating the safety factor of random block is very important for the overall stability evaluation of surrounding rock and the selection of surrounding rock support scheme.In order to accurately calculate the safety factor of key blocks,this paper combines the theory of key blocks with the force transfer algorithm,expanding the traditional theory of key blocks.The force transfer between internal blocks is considered.The improved critical block theory analysis method based on force transfer algorithm is applied to analyze and evaluate the stability direction of blocks.It includes the spatial state classification of typical blocks,the identification of blocks with different levels and the process of force transfer between blocks.Taking the underground rock cavern of Taishan Pumped Storage Power Station as an example,the changes of the safety performance of key blocks in the face before and after force transfer are compared and analyzed,and the supporting effect of the bolt support system for the cavern is evaluated.