【摘要】 研究目的:针对G316江西段改建工程佛头岭隧道施工至软岩区段时发生涌水塌方的工程事故,在深入调查和理论分析的基础上,本文对致灾诱因进行探析并提出处治措施,以此为依据,建立数值计算的对比工况,分析研究隧道涌水塌方的影响机制。研究结论:(1)软弱围岩体、地下水、降雨、地应力等自然因素是本次涌水塌方的内在原因(相对于Ⅴ级围岩,Ⅲ、Ⅳ级围岩拱顶变形分别下降81.7%和50.8%,无渗流作用拱顶沉降下降44.6%);(2)支护不及时和过大开挖步等人为因素是导致本次事故的重要原因(分别致使洞周最大变形处增幅达160%和29%);(3)围岩等级差异是涌水量大小的关键原因(Ⅲ、Ⅳ级围岩的最大日涌水量分别下降92%和78%);(4)监测数据表明,处治措施效果较好,围岩变形得到控制;(5)本研究结果对类似条件下的工程施工和加固处治具有参考价值。更多还原

【Abstract】 Research purposes: The water gushing with collapse in process of reconstruction project tunnel in Jiangxi section of G316 crossing soft rock section is introduced. Based on further investigation and theoretical analysis,the reasons of water gushing with collapse were investigated and treatment measures were proposed. On this basis,the failure mechanism was studied systematically by numerical analysis.Research conclusions:(1) The natural factors such as weak surrounding rock mass,groundwater,rainfall and in-situ stress were the internal causes of this water gushing with collapse,which Ⅲ,Ⅳ grade wall rock dome deformation decreased by 81. 7% and 50. 8% respectively compared to the situation of Ⅴ grade rock and vault settlement reduced by44. 6% under no seepage effect.(2) Human factors such as support is not timely and too much excavation is the main cause of this accident,which caused additional deformation of 160% and 29% respectively.(3) Surrounding rock level difference is the key reason for the amount of water inflow,with the maximum amount of gushing water daily of the Ⅲ,Ⅳ grade wall rock decreased by 92% and 78% respectively.(4) The monitoring data showed that treatment measures were better,controlling the deformation of the surrounding rock.(5) This research result could provide reference value for tunnel construction and treatment measures under similar conditions.更多还原