爆破开挖条件下隧道穿越富水溶洞的安全厚度研究  

Study on the Safe Thickness of Tunnel Passing through Water-rich Karst Cave under Blasting Excavation

作　　者：高军 阎锡东 祝凤金 GAO Jun;YAN Xidong;ZHU Fengjing(China Highway Engineering Consulting Group,Beijing 100089;Zhejiang University,Hangzhou 310027)

机构地区：[1]中国公路工程咨询集团有限公司,北京100089 [2]浙江大学,杭州310027

出　　处：《现代隧道技术》2024年第S01期88-98,共11页Modern Tunnelling Technology

摘　　要：在岩溶地区修建公路隧道会面临岩爆、塌方、突水涌泥等大型地质灾害的威胁,其中岩溶隧道突水对生命财产安全的威胁最大、产生的后果最为严重。为减少隧道施工过程中穿越富水溶腔造成的突涌水危害,采用断裂力学、弹塑性力学模型及爆破理论分析影响隧道与溶腔之间安全厚度的因素,考虑爆破扰动与水压之间的相互作用关系,在总结以往隧道安全厚度计算方法的基础上,建立了基于D-P屈服准则并考虑爆破扰动及溶腔水压力的隧道防突涌水的最小安全厚度弹塑性计算方法,并分析相关因素对最小安全厚度的影响规律。分析结果表明,安全厚度与黏聚力及溶洞水压力存在负相关关系,与原岩应力存在正相关关系;采用云雾山隧道的力学参数进行验证,云雾山隧道施工控制的最小安全厚度为3.5~4.5 m,而理论计算结果为4.44 m,计算值与实际施工中确定的控制厚度较为接近。Highway tunnel construction in karst area will face the threat of large-scale geological disasters such as rock burst,collapse,water inrush and mud gushing,among which the water inrush in karst tunnel is the most serious threat to life and property safety.In order to reduce the water gushing hazard caused by passing through the water-rich karst cavity during tunnel construction,factors affecting the safety thickness between the tunnel and the cavity are analyzed using fracture mechanics,elastic-plastic mechanics models and blasting theory,and the interaction between blasting disturbance and water pressure is considered.On the basis of summarizing the previous calculation methods of tunnel safety thickness,Based on D-P yield criterion and considering blasting disturbance and cavity water pressure,an elastic-plastic calculation method for the minimum safety thickness of tunnel against water inrush is established.The analysis shows that the safety thickness is negatively correlated with the cohesion force and the water pressure of the cave,and positively correlated with the in-situ stress of the rock.The mechanical parameters of Yunwushan tunnel are used to verify that the minimum safe thickness controlled by Yunwushan tunnel construction is3.5-4.5 m,while the theoretical calculation result is 4.44 m.The calculated value is close to the control thickness determined in the actual construction.

关 键 词：岩溶隧道 安全厚度 保护厚度 爆破扰动区 渗透破坏区 动水压力 

分 类 号：U455.6[建筑科学—桥梁与隧道工程]