Abstract:
When the cast-in-situ concrete is used for the tunnel secondary lining constructed by the drilling and blasting method, the construction speed is slow and the arch lining quality is difficult to meet the design requirements. So a partition scheme of prefabricated and assembled secondary lining structure is proposed for the doubletrack railway tunnels constructed by the drilling and blasting method. The stiffness values of transverse and longitudinal joints of prefabricated and assembled secondary lining are calculated on the basis of the calculation theory on segment joints of shield tunnels. Then, the beam-spring calculation model is used to compare and analyze different lining partition schemes, study the stress characteristics of prefabricated and assembled lining with different thickness and determine that the optimal thickness of prefabricated and assembled secondary lining is 500 mm. Meanwhile, the shell-spring calculation model is adopted to analyze the internal force distribution of prefabricated and assembled secondary lining with straight joints and different widths. The results show that the internal force distribution of prefabricated and assembled secondary lining has obvious three-dimensional characteristics, the bending moment is large at the edge of the joint, but small in the middle, and the width of prefabricated and assembled secondary lining should be 2.0 m.
ZHOU Xiaojun1 GUO Jian1 YANG Changyu2 QING Weichen2 XIONG Guoxing2 KUANG Wentao2
.Study on the Partition Mode of Prefabricated and Assembled Secondary Lining of Double-track Railway Tunnels by Drilling and Blasting Method[J] MODERN TUNNELLING TECHNOLOGY, 2021,V58(6): 46-58