大跨度岩体隧道工程块体滑落的概率分析

Probabilistic Analysis on Blocks Sliding of Large-Span Tunnel

介绍了块体理论,在沈阳至大连高速公路韩家岭隧道工程岩体结构面的观测和调研的基础上,引入概率理论对被节理切割的岩体中关键块进行了分析,推导了概率分析模型,从而使原来的一些关键块体转化为稳定块体,使滑落块体的数量更接近实际工程,并应用于韩家岭隧道工程稳定性分析中·初步结果表明,块体理论适用于像韩家岭大跨度隧道工程等局部围岩稳定性分析问题,大跨度岩体工程的稳定性主要取决于结构面的产状和物理力学性质,以及临空面的几何形态,提出的概率分析理论符合工程实际·

The block theory is discussed. Based on in situ examination and analysis about t he Han Jialing tunnel which is part of the key project of the highway to be exte nded from Shenyang to Dalian, both the geological survey and the rock mass chara cteristics in this region are presented. Using probabilistic theory to analyze t he keyblock of the rock mass by point, the model of probalistic analysis was bui lt. It is shown that some keyblocks are transit stability blocks to ensure the n umbers of sliding blocks. It is found that the block theory is suit to analyze s tability of large-span tunnel and the stability of large-span tunnel is relyed on the shape of structure plan, the mechanical parameters and the shape of work space. This theory is proved suitable for the practice of fieldwork.