摘要
依托广东省珠江三角洲水资源输水干线工程,针对LG04^(#)~LG03^(#)盾构区间引水隧洞衬砌外水压的渗透压力最大变化速率波动因素开展分析,阐述了衬砌厚度的变化与隧洞外水压力的响应机制,结果表明:在水头高度较小时,隧洞开挖对整个山体渗流场影响不大,其渗透压力变化较小,随着水头高度的增加,渗流场对隧洞的影响范围随之增大。在地下水头固定的条件下,随着衬砌厚度的增大,衬砌可承受的外水压力逐渐增大。同时,地下水头越大,衬砌厚度的增加对衬砌所能承受的外水压力影响更加显著。增加衬砌厚度是抵抗衬砌外水压力的有效手段,衬砌厚度的增加有助于增强衬砌抵御外水压力和围岩压力的能力,堵水能力也相应增强。根据理论分析结果,在隧道施工过程中采用厚度0.55 m的后张法C50W12F50现浇后张无粘结预应力混凝土内衬结构,工程应用后衬砌外水压力的速率波动得到较好控制。
Relying on the Pearl River Delta Water Resources Transmission Main Line Project in Guangdong Province,an analysis was carried out on the fluctuation factors of the maximum variation rate of the permeability pressure of the water pressure outside the lining of the LG04^(#)to LG03^(#)shield interval diversion tunnel,and the response mechanism of the variation of the lining thickness and the water pressure outside the tunnel was elaborated,the results show that when the head height is small,the excavation of the tunnel has little impact on the seepage field of the whole mountain,and its permeability pressure as the head height increases,the influence of the seepage field on the tunnel increases.Under the condition of a fixed groundwater head,the external water pressure that the lining can withstand gradually increases as the thickness of the lining increases.At the same time,the greater the head,the more significant the effect of increasing lining thickness on the external water pressure that the lining can withstand.Increasing the thickness of the lining is an effective means of resisting external water pressure in the lining,and the increase in lining thickness helps to increase the ability of the lining to resist external water pressure and surrounding rock pressure,and the ability to plug water.According to the results of the theoretical analysis,the rate fluctuation of water pressure outside the lining was better controlled after the project application by using post-tensioned C50W12F50 cast-in-place unbonded prestressed concrete structure lining structure of 0.55m thickness during the tunnel construction process.
作者
谢小帅
XIE Xiaoshuai(Guangdong Gdh Pearl River Delta Water Supply Co.,Ltd.,Guangzhou 510000,China)
出处
《广东水利水电》
2023年第4期17-20,47,共5页
Guangdong Water Resources and Hydropower
基金
广东省重点领域研发计划项目(编号:2019B111108001)。
关键词
引水隧洞
衬砌外水压力
衬砌厚度
衬砌施工
diversion tunnels
water pressure outside the liner
lining thickness
lining construction
作者简介
谢小帅(1995-),男,硕士,助理工程师,主要从事水利工程建设管理工作。
