Design and Construction Optimization of Shield Cutterhead Inspection Shaft Based on Numerical Analysis

As an effective way to inspect and maintain the shield cutterhead, the safety of the inspection shaft is very important in the process of shield tunneling into the shaft. In this study, numerical analysis was adopted to study the interaction of shaft excavation and shield tunneling process and the response law of stratum deformation. Research shows that during the process of the shield tunnelling into the shaft, the bending moment of the enhanced segment of the shaft has the largest change, followed by the lower part of the regular segment and the shield segment. The smaller the shaft excavation space and the more timely the support, the smaller the ground settlement and influence range. The closer the shield support stress ratio is to 1, the smaller the disturbed area of the stratum. It is suggested that The structure strength, monitoring points and monitoring frequency of the enhanced segment and the lower part of the regular segment need to be strengthened. The construction schedule and safety should be taken into consideration when determining the shaft excavation space and shield support pressure.