Abstract:

Metro stations are basically located in urban centers, thus the surrounding environments of the project is significantly complicated. In this context, ground surface settlement induced by construction of the Metro station is studied with respect to its influence on the surrounding environments, in order to select a rational settlementcontrol method. The monitoring data of mined Metro stations of Line No. 7 and Phase 1 of Line No. 6 of Beijing Metro are obtained for detailed analyses. The results show that: 1) The ground surface settlement induced by construction of heading and tunnel arch is of a large magnitude, accounting for 90% of the total settlement; 2) The settlement of different strata excavated by PBA method significantly varies. The settlement of finesilt and mediumcoarse sand strata is the largest, followed by that of silt and silty clay strata, and that of sandycobble strata is the smallest.

Key words: Metro station, PBA method, ground surface settlement, monitoring, settlement troughs, ground loss rate