隧道预切槽法合理支护时机及管片接头结构研究  

Reasonable Support Timing of Tunnel Pre-grooving Method and Research on Segment Joint Structure

作　　者：何伟 范培硕 葛飞 徐莉蓉 杨永香 赵阳 He Wei;Fan Peishuo;Ge Fei;Xu Lirong;Yang Yongxiang;Zhao Yang(Survey,Design and Research Institute of China Railway Tunnel Bureau Group Co.,Ltd.,Guangzhou 511400,Guangdong,China;Guangdong Provincial Key Laboratory of Intelligent Monitoring and Maintenance of Tunnel Structure,Guangzhou 511400,Guangdong,China;College of Geosciences and Engineering,North China University of Water Conservancy and Hydroelectric Power,Zhengzhou 450046,Henan,China)

机构地区：[1]中铁隧道局集团有限公司勘察设计研究院,广东广州511400 [2]广东省隧道结构智能监控与维护企业重点实验室,广东广州511400 [3]华北水利水电大学地球科学与工程学院,河南郑州450046

出　　处：《岩土工程技术》2024年第1期14-21,共8页Geotechnical Engineering Technique

摘　　要：预切槽法是隧道暗挖施工的一种超前支护工法,此工法可大幅度降低地表沉降量,对隧道围岩土体及地表建(构)筑物影响较小。采用室内试验和数值模拟的方法,针对浇筑预切槽管片所用混凝土的前期强度、合理支护时机以及预切槽管片接头处合理的接茬方式进行了研究。研究结果表明,按C30配比的混凝土养护1.5~2 h时即具有6 MPa以上的抗压强度,满足拆模要求;粘接介质对管片环向位移的约束效果明显,环氧树脂可作为优良的管片粘接剂;榫槽式接头榫头角度α的理想范围为55°~70°,综合考虑预切槽工艺的可操作性,榫槽式接头深度B的理想范围为6~8 cm。Pre-grooving method is a kind of over-advance support method for tunnel excavation,which can greatly reduce the amount of surface settlement,and has less impact on the tunnel surrounding rock and soil and surface buildings(structures).Using indoor tests and numerical simulation methods,the research was carried out on the strength of the concrete used for casting pre-grooving duct piece,the reasonable support timing,and the reasonable stubbing method at the joints of the pre-grooving duct piece.The results show that the concrete with C30 proportion has a compressive strength of more than 6 MPa when curing for 1.5~2 h,which meets the requirement of mold removal;the bonding medium has obvious restraining effect on the circumferential displacement of the duct piece,and epoxy resin can be used as an excellent bonding agent for the duct piece;the ideal range of mortise and tenon joint mortise angleαis 55°~70°,and the ideal range of the depth of the mortise and tenon joint is 6~8 cm,taking into consideration of the operability of the pre-grooving process.

关 键 词：预切槽法 混凝土强度 支护时机 接头优化设计 数值模拟 

分 类 号：U455[建筑科学—桥梁与隧道工程]