Abstract: During superlargediameter slurry shield tunneling, clogging problem is common in air cushion chamber due to discharge channel, slurry outlet due to muck size, and slurry circulation system due to unreasonable configuration. Accordingly, a case study is conducted on the Shenzhen Chunfeng tunnel project, and study is carried out on the slurry circulation system of a superlargediameter slurry shield. Based on the principle of fluid mechanics, the key parameters of the slurry circulation system of superlargediameter slurry shield are calculated, realizing reasonable configuration of slurry flow rate, pipe diameter, and pump station, and improving the adaptability of the slurry circulation system to the slurry with large particle size and high velocity. On the basis of theoretical research, the front gate direct mucking mode is designed to reduce the risk of delayed mucking, the main machine small cycle model is designed to improve the muck carrying capacity of main machine, and the classification crushing technology of main machine mucking is applied to prevent the large size of stone from blocking the discharge mouth and slurry pump. According to the construction results of Shenzhen Chunfeng tunnel, the method recommended can effectively reduce the risk of delayed mucking in key positions such as slurry chamber, air cushion chamber, and discharge port.

Key words: superlargediameter slurry shield, slurry circulation system, parameter configuration, delayed mucking