基于能量法的地下隧洞动静力稳定性分析
Dynamic and Static Stability Analysis of the Underground Tunnel Based on Energy Method
作者：白琦(武汉大学 水资源与水电工程科学国家重点实验室, 湖北 武汉 430072;武汉大学 水工岩石力学教育部重点实验室, 湖北 武汉 430072)；肖明(武汉大学 水资源与水电工程科学国家重点实验室, 湖北 武汉 430072;武汉大学 水工岩石力学教育部重点实验室, 湖北 武汉 430072)
Author：BAI Qi(State Key Lab. of Water Resources and Hydropower Eng. Sci., Wuhan Univ., Wuhan 430072, China;Key Lab. of Rock Mechanics in Hydraulic Structural Eng. of Ministry of Education, Wuhan Univ., Wuhan 430072, China)；XIAO Ming(State Key Lab. of Water Resources and Hydropower Eng. Sci., Wuhan Univ., Wuhan 430072, China;Key Lab. of Rock Mechanics in Hydraulic Structural Eng. of Ministry of Education, Wuhan Univ., Wuhan 430072, China)
收稿日期：2018-02-25 年卷（期）页码：2018,50(3):247-255
期刊名称：工程科学与技术
Journal Name：Advanced Engineering Sciences
关键字：能量;岩体单元;整体破坏;地下隧洞;稳定性;地震
Key words：energy;rock mass element;global failure;underground tunnel;stability;earthquake
基金项目：国家重点基础研究发展计划资助项目（2015CB057904）；国家自然科学基金资助项目（51579191）
中文摘要
通过分析前人研究岩体单元变形破坏过程中能量演化的试验数据，表明岩体单元的可释放弹性能储能极限与岩体单元所受应力状态和岩性有关；基于岩体单元整体破坏失稳的定义，推导了不同应力状态下岩体单元的整体破坏失稳准则；基于热力学第二定律和最小能量原理，提出地下洞室动静力失稳判别准则；运用有限差分数值分析软件FLAC3D，以完建期有无地震动作用的某地下隧洞工程为例，分别进行有无支护工况下地下隧洞的动静力稳定性分析。研究表明：该地下隧洞在所有静力工况和地震工况3下只会发生应力型局部失稳，在地震工况1和2下极有可能发生应力型整体失稳。无支护工况、施加喷锚支护工况和施加喷锚与二衬支护工况下的地下隧洞受地震动作用后洞周发生整体破坏的岩体单元体积分别增加了1 553.15、1 091.79、223.07 m3，可知施加衬砌支护后发生整体破坏的岩体单元体积的减少幅度大于施加喷锚支护后发生整体破坏的岩体单元体积的减少幅度，表明衬砌支护的抗震效果好于喷锚支护。本文提出的地下洞室动静力失稳判别准则可作为采用数值模拟手段研究地下洞室动静力稳定性的有效判据，研究成果能为地下洞室的设计和施工提供有益参考。
英文摘要
The experimental data of previous researches on the energy evolution during the rock mass element's deformation and failure process was analyzed,and the conclusion shows that the releasable elastic strain energy limit of the rock mass element is related to the stress state and lithology.Then,the global failure and instability criterion for the rock mass element under different stress states was derived secondly based on the definition of global failure and instability.Moreover,the criterion for assessing dynamic and static instability of the underground cavern was proposed based on the second law of thermodynamics and the principle of minimum energy.Finally,the dynamic and static stability analysis of an underground tunnel with/without support was brought out based on the example of an underground tunnel under the action of earthquake motion in the construction period,by means of FLAC3D.The results show that the stress-type local instability failure occurred in the underground tunnel in all of static conditions and also the third condition with earthquake occurring,and the stress-type global instability failure most probably occurred in the underground tunnel in the first and second earthquake conditions.After the action of an earthquake,the volume of global failure and instability's rock mass element was increased by 1553.15 m3、1091.79 m3and 223.07 m3,in the no-support condition,the shotcrete-bolt support condition and the shotcrete-bolt and lining support condition,,respectively,indicating that the earthquake-resistant effect of the lining support is better than that of the shotcrete-bolt support.The discriminant criterion for dynamic and static instability of the underground cavern proposed in this paper is a useful for the numerical simulations of dynamic and static stability of underground caverns,and the calculation results can provide useful references for the design and construction of underground caverns.
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