Monitoring And Study On Deformation Behavior Of Deep Foundation-pit With Pile And Inner Concrete Support Under Complex Conditions

As a result of rapid economy development, urban architectures can't meet the need for living space gradually, construction of underground engineering is an effective and important way to improve the using rate of urban ground. However, the excavation area and depth of foundation-pit are more and more large, and the surrounding environment is also complex. Pile with inner concrete support is one popularly used method in this condation. It's important to implement comprehensive dynamic monitoring for controling the deformation of foundation pit support, surrounding building underground pipeline and other structures.This article took project of "Security monitoring and rapid construction technology of large underground civil defense under complex condition in Shenyang North-station" as an studying object, estimate the maximum horizontal displacement of fender pile, the uplift of pit-bottom and the ground settlement according to the theories of slope stability and soil deformation; the law of displacement of pile, earth pressure of piles, axial force of inner concrete support, uplift of temporary pillar piles, settlement of surrounding buildings and underground pipeline, underground water-level is got through systematic dynamic monitoring and measured data analyzing; finally, comprehensive studies of support structure force and surrounding soli deformation under different support position, cross section of concrete support, pile diameter and embedded depth of piles were made based on the finite element software MIDAS/GTS. The above researches provide a theoretical basis for the foundation pit under complex condition, it has important theoretical value and engineering practical significance.