【摘要】 为了保障高压富水区山岭隧道施工安全,现场经常采用注浆堵水措施,而目前隧道注浆堵水时地下水渗水量和支护结构外水压力变化特性尚有待于进一步研究。依托南大梁高速公路华蓥山隧道工程,基于复合式衬砌山岭隧道"堵水限排"的防排水理念,采用理论分析和数值模拟方法,分析了高压富水区复合式衬砌山岭隧道围岩注浆堵水时地下水渗流场特征,推导了高压富水区山岭隧道采取注浆堵水时隧道渗水量和支护结构外水压力的计算公式,得到了隧道渗水量及支护结构外水压力与注浆圈厚度、围岩和注浆圈渗透系数之比及围岩和初期支护渗透系数之比间的关系。研究结果表明:高压富水区山岭隧道注浆堵水时,隧道渗水量和支护结构外水压力的主要控制因素为:注浆圈厚度、注浆圈及初期支护的渗透系数;隧道渗水量和支护结构外水压力随着注浆圈厚度的增加及其渗透系数的减小而降低,综合考虑注浆堵水效果及施工成本,建议注浆圈厚度为6～8 m、围岩与注浆圈渗透系数之比为100～200时较优;高压富水区山岭隧道防排水系统设计,需要考虑注浆圈和初期支护堵水作用以及横纵向排水管排水效果,即综合防排水设计才可以减小排水量,有效降低支护结构外水压力。研究所得隧道注浆堵水的相关参数成功应用于实际工程,为高压富水区隧道工程注浆堵水设计与施工提供了一定的参考。更多还原

【Abstract】 The grouting is adopted for the mountain tunnel in high pressure and water-rich region as a countermeasure to guarantee smooth construction. The variation characteristics of groundwater seepage quantity and external water pressure on the support structure in the grouting process still needs further study. Based on the Huayingshan tunnel engineering project of Nanchong-Dazhu-Liangping expressway and under the guidance of the water control & drainage concept of "plugging groundwater and limiting drainage" for composite lining,by using both theoretical analysis method and numerical simulation method,the seepage field characteristics of surrounding rock of tunnel with composite lining in high water pressure and water rich region in the grouting process is analysed,and a formulas for calculating the groundwater seepage quantity and external water pressure of the tunnel support structure in high pressure and water rich region when grouting are derived. The relationships of the ratios of seepage quantity and external water pressure to thickness of grouting ring,permeability coefficient of surrounding rock and grouting ring,and the ratio of permeability coefficient of surrounding rock to permeability coefficient of primary support are calculated. The result reveals that(1) In the grouting process of the tunnel at high pressure and water rich region,the external water pressure and the groundwater seepage quantity mainly decided by the thickness of grouting ring and the permeability coefficients of grouting ring and primary support.(2) The groundwater seepage quantity and external water pressure decreasing with the increase of the thickness of grouting ring and the decrease of its permeability coefficient. With the comprehensive consideration of water plugging effect and construction cost,the suggested optimum thickness of the grouting ring is 6-8 m,and the optimum ratio of permeability coefficients of surrounding rock to grouting ring is 100-200.(3) The water-proof and drainage system design for the mountain tunnel needs to consider the water plugging result of the grouting ring and primary support and the drainage effect of transverse and longitudinal drainage pipes in the high pressure water rich area,i.e.,the comprehensive water-proof and drainage system design could reduce the groundwater seepage quantity and effectively decrease the external water pressure. The water grouting plugging parameters of tunnel from this study have successfully applicant to construction of tunnel project,which provides a reference for the design and construction of grouting and plugging for tunnel in high pressure and water rich region.更多还原