Abstract: The difficulties and key technical problems in the shield cutting pile foundation group of cast-in-place piles of Qianhubeilu Station-Qiubi Station Section of 3103 Bid of Ningbo Metro Line No. 3 are studied in detail based on the existing construction technology; and the corresponding technical schemes are made for a series of problems during the pile foundation group cutting. Analysis is carried out on the parameters variation, condition of cutting tool, statistics of concrete reinforcement and monitoring results of surface settlement and surrounding buildings. The analytical results show that good effects, i. e. no large abrasion of cutting tool, no crack and leakage of segment and controllable surface and building settlement, have been achieved, which indicates the feasibility and advantages (such as economical, safe and little impact on surrounding environment) of the construction scheme adopted.

Key words: shield, metro tunnel, pile foundation cutting, settlement monitoring