Study On The Depth Of Adjacent Building Basement To The Stability Of Foundation Engineering

With a large numbers of people settling in cities,urban land is becoming more and more intense.In order to improve the utilization ratio of urban land,it's universial that urban buildings develop toward the air and underground.The application of deep foundation pit engineering is more and more extensive.The deep foundation pit engineering city buildings are located in densely populated areas and the surrounding environment is more complex.Adjacent buildings have additional load on the excavation process of deep foundation pit.And the stability of deep excavation is impacted by the factors above.The research of the impact on foundation pit excavation by the adjacent building load has become more important.Based on the study of the influence of the load depth on the excavation of deep foundation pit,reasonable proposals are made for the design of excavation under the action of additional load through the combination of numerical simulation and practical engineering.Firstly,through the theoretical analysis,this paper obtains the approximate formula of the earth pressure distribution of the retaining wall in the basement of the adjacent building,and analyzes its influence factors on the earth pressure of the retaining wall.After that,with the numerical simulation of the excavation process of deep foundation pit engineering Kaba crystal,it analyzes the displacement of soil and piles.Analysis shows that:First,by comparing the numerical simulation results with the actual monitoring results,it is found that the simulation results are basically consistent with the actual monitoring results,indicating that numerical models can effectively simulate the impact of adjacent building loads on foundation pit excavation.secondly,by comparing two kinds of simulation results of basement,it is found that the existence of basement affects the excavation of foundation pit.Then,GTS NX numerical simulation software is applied to establish foundation pit excavation models with different load depths.The analysis process is divided into two stages.Initial analysis stage and post excavation stage analyze the variation of soil stress and displacement and displacement of pile.Analysis shows that: First,with the increase of load depth,soil stress and displacement of maximum shear strain and displacement and pile load increase with depth.Secondly,there exists a critical depth of excavation is about 0.8 times the depth of excavation.When the load is less than the critical value,the adjacent building has negative effects on xcavation.When the load is greater than the critical value,the existence of the adjacent buildings have favorable effect on excavation.Thirdly,with the increase of load value,the critical value of the increase of the depth of the pit depth impact load.The research results show that in the process of deep foundation pit design and construction,we should take full account of the beneficial effects brought by the depth of additional load of buildings,so as to make it more economical under the premise of deep foundation pit safety.