Abstract:

In the paper, the main factors that influence the tunneling efficiency of EPB shield are summarized, with the shield tunneling of the running tunnel from Heping Hospital station to Lieshilingyuan station on Line 1 of Shijiazhuang Metro as example. Conclusions drawn are as follows: 1) Shield boring and segment erection are relatively simple tunneling processes, which are related to the geological conditions and the proficiency of the operation labors; 2) The supply of the segments from the ground surface to the bottom of the vertical shaft and the hoisting of the mucks from the shaft bottom to the ground surface are related to the layout of the facilities at the job site, therefore, the facilities at the job site should be well planned before shield boring is started; 3) The optimization of the repair and maintenance of shields and their backup equipment, the replacement of the vulnerable parts, the shield tunneling survey and the moving of the survey stations can further improve the tunneling efficiency.

Key words: Shijiazhuang Metro, EPB shield, boring rate, influence factor, tunneling efficiency