明挖预制装配式隧道结构拼装设计方法及关键技术  

Design Method and Key Technology for Assembling Open-excavated Prefabricated Tunnel Structures

作　　者：杨秀仁 YANG Xiuren(National Engineering Research Center for Green and Safe Construction Technology in Urban Rail Transit,Beijing 100037;Beijing Urban Construction Design and Development Group Co.,Ltd.,Beijing 100037)

机构地区：[1]城市轨道交通绿色与安全建造技术国家工程研究中心,北京100037 [2]北京城建设计发展集团股份有限公司,北京100037

出　　处：《都市快轨交通》2023年第2期2-13,共12页Urban Rapid Rail Transit

基　　金：国家重点研发计划(2017YFB1201104);北京城建集团创新项目(CJJT2022-002)。

摘　　要：明挖施工条件下的预制装配式隧道结构,其拼装技术与装配整体式结构或盾构隧道均存在较大差别。在工程设计阶段,需要根据结构型式和装配模式,对拼装进行详细的规划和设计,以支撑高质量、高效率施工,并确保结构承载性能和稳定性,同时满足接头接缝防水性能要求。拼装关键技术包括拼装方法、基面精平技术、定位控制技术、张拉锁紧技术、支顶限位措施、精度控制标准等方面。明挖装配式隧道结构的拼装应以首环固定端为起点,沿纵向推进,遵循“先下后上”并逐块、逐层向上的拼装原则;基坑底部基面应进行精平处理,并根据地基条件和底板结构型式,采用精平条带法或基面统平法;隧道衬砌结构宜在接头拼接面设置一定数量的导向定位装置,在辅助构件精确定位的同时,有效控制结构表面错台量;明挖装配式隧道宜设置在直线上,当隧道位于曲线地段时,可采用“楔形构件+等宽缝”或“等宽构件+楔形缝”的方式拟合曲线;张拉锁紧措施主要有预应力钢棒张拉锁紧和螺栓锁紧方式,预应力张拉宜采用“形心跟踪法”,并应多点协同、同步张拉锁紧,保持接缝宽度的均匀性,有效控制目标接缝张开量,并对预制底板下空隙及时注浆填充,在侧墙和拱脚等关键部位及时支顶限位。The assembly technology of prefabricated tunnel structures for open-excavated construction differs significantly from that for shield tunnels.In the engineering design stage,the structural assembly needs to be planned and designed in detail according to the structural type and assembly mode to support high-quality and efficient construction to ensure the bearing performance and stability of the structure,and meet the waterproof performance requirements of the joints.The key assembly technologies include the assembly method,base surface fine leveling technology,positioning control technology,tension-locking technology,roof support limit measures,and precision control standards.The open-excavated prefabricated tunnel structure took the fixed end of the first ring as the starting point,proceeded along the longitudinal direction,and followed the principle of“from bottom to top”and assembly block by block and layer by layer.The base surface at the bottom of the foundation pit was finely leveled,and according to the foundation conditions and structural type of the bottom plate,the fine leveling strip method or foundation surface leveling method was adopted.The tunnel lining structure should be equipped with a certain number of guiding and positioning devices at the joint assembly surface to effectively control the dislocation of the structure surface and help locate the components accurately.The open-excavated prefabricated tunnel was set in a straight line.When the tunnel was located in a curved section,the curve was fitted by means of a“wedge-shaped component+equal width joint”or“equal width component+wedge-shaped joint.”Tensioning and locking measures included the use of prestressed steel bars or bolts.The“centroid tracking method”was used for prestressed tensioning,and the multi-point coordination and synchronous tensioning and locking were used to maintain the uniformity of the joint width,effectively control the opening of the target joint width,allow the timely filling of the gap under the prefab

关 键 词：明挖装配式隧道 拼装设计 干式连接 湿式连接 精平条带法 基面统平法 定位销棒 曲线隧道 预应力张拉锁紧 螺栓锁紧 形心跟踪法 支顶限位 

分 类 号：U231[交通运输工程—道路与铁道工程]