地铁暗挖区间装配式二衬结构施工技术

Construction Techniques of the Prefabricated Secondary Lining for the Undercut Section of a Tube

结合某地铁暗挖隧道工程的马蹄形管片拼装施工,对暗挖隧道装配式二次衬砌结构施工工艺进行介绍。即在已完成初期支护的隧道中,利用初支仰拱部位施作的高精度混凝土导台对预制马蹄形管片进行定位,采用管片拼装设备对预制管片进行拼装,并通过纵、环向平直螺栓将管片连接成整体,豆砾石+浆液填充二衬管片与初支间隙,完成永久性支护。与全现浇建造方式相比,装配式二衬施工在工程进度、环保、经济等方面都有着显著的优势。

With the assembly construction of the horseshoe segments of the undercut tunnel of a certain tube as a practical example, introduced in the present paper is the construction technology for the prefabricated secondary lining of the undercut tunnel. That is, inside the initial lining-completed tunnel, the high-precision concrete guiding platform cast at the initially-supported inverted arch is made use of to position the prefabricated horseshoe segments, with the segment-assembling equipment used to assemble the prefabricated segments, with longitudinal and circular straight bolts to connect the segments into a whole and with pea gravels + mortar used to fill the gaps between the secondary lining segments and the initial lining so as to finish the permanent support. Compared with the building method of the full-site-casting, the prefabricated secondary lining construction has obvious advantages in either construction progress, environmental protection, economic aspect or other aspects.