路堤填筑对下覆输水隧洞的影响及减载设计  

Influence Analysis and Load Reduction Design of Embankment Filling on Overlying Water Conveyance Tunnel

作　　者：吕利 孙波[2] 谭彩 LYU Li;SUN Bo;TAN Cai(Technical Advisory of Pearl River Water Resources Commission(Guangzhou)Co.,Ltd.,Guangzhou 510611,China;Comprehensive Technology Center of Pearl River Water Resources Commission of the Ministry of Water Resources,Guangzhou 510611,China;Guangdong Research Institute of Water Resources and Hydropower,Guangzhou 510635,China;State and Local Joint Engineering Laboratory of Estuarine Hydraulic Technology,Guangzhou 510635,China)

机构地区：[1]水利部珠江水利委员会技术咨询(广州)有限公司,广东广州510611 [2]水利部珠江水利委员会珠江水利综合技术中心,广东广州510611 [3]广东省水利水电科学研究院,广东广州510635 [4]河口水利技术国家地方联合工程实验室,广东广州510635

出　　处：《人民珠江》2023年第12期94-100,共7页Pearl River

基　　金：广东省水利科技创新项目(2022-03);水利部水利技术示范项目(SF-201910)。

摘　　要：路堤填筑将对下覆输水隧洞结构产生不利影响,为降低路堤填筑对下覆输水隧洞的影响,提出了在隧洞两侧设置灌注桩的减载方案,并采用有限元对未设置灌注桩减载及不同桩间距、桩体弹性模量和桩体排数的灌注桩减载加固后输水隧洞进行模拟,同时在典型断面设施监测点,监测隧洞衬砌顶拱、拱腰、边墙、底板、边墙与底板连接点的应力和变形情况,分析了桩间距、桩体弹性模量和桩体排数对隧洞减载效果的敏感性。结果表明:①路堤填筑将造成隧洞衬砌顶拱竖向变形达到5.45 cm,边墙和地板交接处,混凝土所受拉应力达到8.34 MPa,超过结构抗拉强度容许值,衬砌处于不安全状态;②通过设置灌注桩可以有效降低路堤填筑对输水隧洞的不利影响,提高输水隧洞的安全性;③输水隧洞减载效果与桩体间距和桩体排数显著相关,与弹性模量相关性相对较小。Embankment filling will have adverse effects on the structure of the overlying water conveyance tunnel.In order to reduce the impact of embankment filling on the overlying water conveyance tunnel,a load reduction plan was proposed by setting cast-in-place piles on both sides of the tunnel.Finite element analysis was used to simulate the water conveyance tunnel without load reduction of cast-in-place piles and that with load reduction and reinforcement of cast-in-place piles under different pile spacing,pile elastic modulus,and pile row numbers.At typical section facility monitoring points,the top arch and arch waist of the tunnel lining were monitored.The stress and deformation of the connection points between the side wall,bottom plate,and side wall and bottom plate were analyzed,and the sensitivity of pile spacing,pile elastic modulus,and pile row number to the tunnel load reduction effect was analyzed.The results indicate that:①Embankment filling will cause a vertical deformation of 5.45 cm in the top arch of the tunnel lining,and the tensile stress on the concrete at the junction of the side wall and floor will reach 8.34 MPa,exceeding the allowable value of the structural tensile strength.The lining is in an unsafe state.②By setting cast-in-place piles,the adverse effects of embankment filling on the water conveyance tunnel can be effectively reduced,and the safety of the water conveyance tunnel can be improved.③The load reduction effect of the water conveyance tunnel is significantly correlated with the pile spacing and pile row numbers,while the correlation with the elastic modulus is relatively small.

关 键 词：隧洞 应力 变形 填方 减载 灌注桩 

分 类 号：TV672.1[水利工程—水利水电工程]