大型分岔隧道围岩稳定与支护 三维地质力学模型试验研究

 分岔式隧道是一种新型隧道结构型式，目前尚无相应的设计、施工技术规范和标准可循，为了解这种新型隧道结构的应力和变形状况，采用三维地质力学模型试验方法对目前在建的沪蓉西高速公路大型分岔隧道进行研究。试验成果有效地揭示分岔隧道洞周的应力、位移变化规律和分岔隧道围岩的破坏机制，获得分岔隧道的设计和极限承载安全度，为分岔隧道的优化设计和施工提供了有工程指导意义的建议和结论。

3D GEOMECHANICAL MODEL TEST RESEARCH ON STABILITY AND SUPPORTING FOR SURROUNDING ROCK MASS OF A LARGE-SCALE DIVERSION TUNNEL

Diversion tunnel is a new type tunnel structure. There is not any technical standard of design and construction for the diversion tunnel at present. A large-scale diversion tunnel of highway under construction is studied through the 3D geomechanical model test method in order to understand stress and deformation situations of surrounding rock mass of the diversion tunnel under excavation state. The changing laws of stress and displacement around the tunnel and the failure mechanism for the surrounding rock mass of tunnel have been effectively revealed after test. The design and limit load-bearing safety reliability for the diversion tunnel have also been achieved. According to results of the model test，some useful suggestions and conclusions for the optimization design and construction of the diversion tunnel have been proposed.