关键词: 富水砂层, 无端头加固, 土压平衡盾构, 水下接收

Abstract: The safe reception of shield in waterrich sandy layer without end reinforcement should be guaranteed. Hence, the key construction technology of shield reception in water by means of filling water into the shaft is studied based on the Red Line Light Rail Project in Tel Aviv, Israel. Main studies and conclusions are as follows: (1) By carrying out measures i.e. concrete cradle, portal seal, screw seal, shield tail seal, shield tunneling parameter control, grouting control, etc., the shield is received safely in the shaft, the construction efficiency is improved and construction cost is reduced. (2) According to theoretical calculation and practical verification, the sand can be prevented from being taken out of the excavation gap by injecting water about 1 m above the groundwater level into the shaft. (3) Rational shield sealing control can avoid water gushing and sand gushing accidents. (4) The doublelayer concrete cradle in the shaft is conducive to shield attitude adjustment and smooth pushing on the steel cradle. (5) After rigorous construction organization and design, two EPB shields have successfully completed underwater reception; there was no sand gushing in the shaft, and the ground settlement was controlled within the prescribed value, which can provide reference for similar shield reception projects in the future.

Key words: waterrich sandy stratum, noend reinforcement, EPB shield, underwater receiving