Research on the impact of open descending confined water under sandy stratum on the environment surrounding the foundation pit of metro station
Aiming at the deep foundation pit of metro station with deep and think chalky soil and sandy stratum at the bottom of the pit,the finite difference groundwater flow modeling software Modflow is used to establish a three-dimensional numerical computation model,and combined with the on-site pumping test and the monitoring results of the surface settlement around the foundation pit,the research is conducted to find out the distribution principle of the settlement of the confined aquifer and the overburden layer caused by the descending confined water and the influence of the size of the surface settlement outside the pit caused by the descending confined water.The research shows that the settlement of the overlying soil layer of the confined aquifer based on the layered sum method is much smaller than the total settlement,and the surface settlement outside the pit caused by the descending confined water is about 0.04 times of the compression amount of the confined aquifer;when the depth of the stop curtain inserted into the confined water layer is more than 50%,increasing the length of the stop curtain per unit is more effective in reducing the surface settlement outside the pit;in the case of open descending confined water,increasing the depth of the confined water head drop has a greater effect on the surface settlement outside the pit than the change in the length of the stop curtain inserted into the confined water layer.The conclusion of the research can provide a reference for the subsequent deep foundation pit descending in similar deep and thick chalky soil and sandy stratum.
metro stationfoundation pitchalky soil and sandyconfined watersurface settlement
万方数据
维普
