Design and Engineering Application of Prefabricated Structure for Secondary Lining Arch of Double-Track Railway Tunnels Constructed by the Mining Method
(1. School of Civil Engineering, Southwest Jiaotong University, Chengdu 610031; 2. East Ring Line Construction Headquarters of Chongqing Railway Hub of China Railway Chengdu Bureau Group Co. Ltd., Chongqing 400023; 3. China Railway Eryuan Engineering Group Co., Ltd., Chengdu 610031)
Abstract：
Tunnel construction through the mining method with cast-in-place concrete lining often fails to complete? ly eliminate common quality defects, such as insufficient thickness of concrete lining, insufficient strength, cracking and spalling, and void behind in tunnel arch, which poses threats to the long-term safe operation of railway tunnels.This paper relies on the Hujiagou Tunnel Project of the East Ring Line of Chongqing Railway Hub and proposes to use assembled secondary lining for the arch of the composite lining by combining prefabricated blocks and sidewall molded lining. This paper analyzes the blocking method and joint structure of the prefabricated lining in the arch,summarizes the construction process and economy of the prefabricated lining structure, and analyzes the safety and durability of the lining structure according to field monitoring results. The results show that the structural parameters of the initial support and assembled secondary lining designed for the prefabricated lining test section of the arch of the Hujiagou Tunnel are feasible, and the lining allows for sufficient safety; The form of joints for the prefab? ricated lining of the arch and the cast-in-place sidewall should be designed in the form of a circular arc; The total cost of the scheme of secondary lining with prefabricated arch increases by RMB 3,147,100 compared with the total cost of the cast-in-place secondary lining, and the comprehensive cost increases by RMB 28,600/m.
ZHOU Xiaojun1 NING Yuansi2 YANG Changyu3
.Design and Engineering Application of Prefabricated Structure for Secondary Lining Arch of Double-Track Railway Tunnels Constructed by the Mining Method[J] MODERN TUNNELLING TECHNOLOGY, 2022,V59(4): 204-217
2022, Vol. 59 