摘要
松散软岩巷道的开挖与支护问题一直是理论与工程难题,围岩破坏机理则是围岩变形控制的关键。结合具体工程,针对一种典型的松散软岩,根据其地质条件和物理力学特性,采用颗粒离散元软件对软岩中巷道的开挖过程进行了数值模拟。文章还再现了软岩从开挖到破坏的整个力学演变过程,以及围岩在一定范围内从裂隙产生到贯通的整个渐进式破坏过程,详细分析了围岩各个关键部位的应力特征,得到巷道围岩应力分布特征图。在等围压的情况下,岩体还表现出较好的成拱效应,能够较好地自稳,得到巷道围岩成拱示意图。分析结果与巷道弹塑解能很好地吻合。以上结果表明,颗粒离散元对类似的岩土工程力学过程和机制的分析有很好的运用前景。
The loose soft roadway excavation and maintenance has been one of the major theoretical and engineering concerns, the fracture mechanism has been the key of deformation control for the rock. Based on the specific geological feature, physical and mechanical properties of rock, the particle flow code is used to simulate the process of tunnel excavation and failure of surrounding rocks. When without support, the whole stress development process of the soft rock from excavation to failure is shown, as well as the progressive failure of surrounding rock in a certain range of crack from its generation to cut through. By analyzing the stress distribution of different part in surrounding rock in detail, the figure of the stress distribution＇ s characteristics of surrounding rock has been gained. When the lateral pressure coefficient is 1.0, the surrounding rock will form arch easily, and to be stabilized, then the figm＇e of pressure arch in the surrounding rock is obtained. The results meet those of the elastic-plastic analysis well. The relevant results by particle flow code may provide reference to similar geotechnical or underground engineering problems.
出处
《地下空间与工程学报》
CSCD
北大核心
2010年第2期318-322,共5页
Chinese Journal of Underground Space and Engineering
基金
973项目(2007CB714203)
北京市自然科学基金
北京市教育委员会科技计划重点项目(KZ200910005009)
国家自然科技基金项目(40972187)
关键词
松散软岩
颗粒离散元
破坏机理
loose soft rock
particle discrete element
failure mechanism
