Key Construction Technologies for Overlapping Twisted Shield-bored Tunnels in Weak Water-rich Strata
(2.Department of Civil Engineering, Shanghai University, Shanghai, China 200444)
【Abstract】The project under study is an overlapping twisted shield-bored tunnels in weak water-rich strata. The purpose of the study is to solve the key technological problems in the construction of the project. The optimal construction sequence of the overlapping twisted shield tunnels is determined according to the engineering geological conditions, the surrounding working environment, and the theoretical analysis on the spatial relationship of the four tunnels, and verification control are carried out via monitoring means. The tunnel construction is properly timed, a smart self-propelled movable support jumbo is adopted, and grouting reinforcement technology is used to ensure the construction safety of the overlapping twisted shield-bored tunnels. The grouting pre-reinforcement technology and the clay shock technology are adopted to ensure the safety of the surrounding buildings. The technologies for the construction of the overlapping twisted shield-bored tunnels described in this paper is of great significance for the construction of similar overlapping tunnels with high shield launching/receiving risks and crossing under important structures with small clearance.
【Keywords】 weak water-rich strata; overlapping twisted shield-bored tunnels; smart self-propelled movable support jumbo; grouting reinforcement;
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