Abstract:
Based on a tunnel project in Shenzhen, this study is to investigate the construction technologies for slurry balance shields with super-large diameter through faulted fracture zones. The study analyzes the engineering characteristics and challenges of slurry balance shields with super-large diameter through faulted fracture zone, with a focus on the causes of different problems, such as clogging discharge, caking and serious tool wear during the boring process of the slurry balance shield, and investigates the key technologies for slurry balance shields through faulted fracture zones. To address the problems of clogging discharge and caking, the study optimizes the design of the cutter head structure during the selection phase of the shield machine, and adopts targeted measures, such as large grating plus crushing system with double crushers to discharge slags, small circulation mode with air-cushioned direct discharge at the host section, to improve the slag carrying capacity and conveying capacity of the slurry and reduce the risk of clogging discharge and caking. In view of the serious problem of tool wear, this study puts forward the tool management guideline of strengthening monitoring over the tool conditions, "inspecting upon warning and replacing a tool with any damage", and eliminating "working with problems", with the objectives to ensure the reliability and accuracy of tool condition monitoring and improve the life of tools. Finally, this paper summarizes the construction principles of "early prevention with control and comprehensive management of problems" through field practice, and adopts the supportive pneumatic tunnelling mode to cross the faulted fracture zone. Through the study and analysis of the construction process, this study deduces the recommended values of shield tunnelling parameters and slurry parameters and different targeted solutions
LIU Zhi1 ZHONG Changping2
.Research on Key Technologies for Tunnelling in Faulted Fracture Zones by Slurry Balance Shields with Super Larg[J] MODERN TUNNELLING TECHNOLOGY, 2023,V60(1): 225-232