压力隧洞渗透稳定的参数敏感性分析

为了研究压力隧洞渗透稳定性与围岩变模、围岩渗透系数、地应力、衬砌类型及厚度等的关系,建立了压力隧洞内水外渗的渗流-应力-开裂耦合计算模型,拟定了不同围岩渗透系数、不同围岩变模、不同初始地应力、不同衬砌类型及厚度等组合的一系列工况,运用上述计算模型对压力隧洞内水外渗进行了计算.根据计算结果,以隧洞综合透水率和破坏内水压力为渗透稳定性指标,对围岩渗透性、围岩变模、地应力及侧压力系数、衬砌是否配筋、衬砌厚度等影响因素进行了参数敏感性分析,给出了各参数对压力隧洞综合透水率及破坏内水压力的影响程度.研究成果可为压力隧洞设计,尤其是衬砌型式选择提供参考依据.

Parameter Sensitivity Analysis for Seepage Stability of Pressure Tunnel

In order to study the relationship between seepage stability of pressure tunnel and each of surrounding rock permeability coefficient,surrounding rock deformation modulus,geo-stress,lining type and thickness separately,a seepage-stress-cracking coupling numerical model for pressure tunnel internal water exosmosis was established.Analysis cases of different surrounding rock permeability coefficient,surrounding rock deformation modulus,initial geo-stress,lining type and thickness were programmed and internal water exosmosis calculations were carried out by using the above mentioned model.Using permeability rate and destroyed hydraulic pressure as the seepage stability index,parameter sensitivity analysis of surrounding rock permeability and deformation modulus,geo-stress and lateral pressure coefficient,lining type and thickness were conducted based on the calculation results.Effect degree of various factors on the permeability rate and destroyed hydraulic pressure of pressure tunnel were presented.The results presented herein can provide reference guidelines for the design of pressure tunnel and lining selection.