Numerical Simulation Analysis and In-situ Monitoring of Long, Narrow and Deep Foundation Pit

Abstract

According to the characteristics of long, narrow and deep foundation pit, the displacement distribution of X-axis with different length-width ratios of 1:1, 2:1 and 3:1 were emphatically analyzed, and then the displacement distribution of Y-axis at the slope bottom and the displacement distribution of Z-axis at the foundation bottom were studied. Then, the different displacement distribution law of pile-anchor support and soil nailing wall support were analysed in different excavation processes considering in-situ supporting schemes, and the different supporting effects of the two supporting structures were presented on the stability of foundation pit slope. By comparing the monitoring values at the 32 in-situ positions, the numerical simulation result was basically identical with the monitored data, on average 3mm higher than the measured value. By using MIDAS software, the excavation and supporting process of the foundation pit could be simulated, and it can provide guidance for the construction of long and narrow deep foundation pit and adjust the monitoring period appropriately.