Monitoring And Interaction Analysis Of Adjacent Foundation Pit

The key job of this paper is analyze the four phases of the excavation of foundation it of Hen Qing by comparing the three-dimensional numerical model and field monitoring data which is based on both the research topic " Simulation research and application of adjacent super deep foundation pit construction in soft soil stratum" of CCCC4 and Rail transit station foundation pit excavation engineering and Hen Qin XinDe Mansion of Zhu Hai City.The main contents of the analysis include wall deflection of underground continuous wall foundation pit of Hen Qin and the settlement of foundation pit soil etc.Finally,analyzing the influence of both project on each other by three dimensional numerical simulation.(1)The consequence can be drawn by comparing numerical model and the field monitoring data is that reinforced concrete support and steel support play different role in the job of top support.Reinforced concrete support can be both tension and compression,as a result,it can effectively control the displacement of the top of the wall as well as the deformation of the top of the underground continuous wall,furthermore the deformation of the lower wall can be controlled much better.At the same time,the deformation of underground continuous wall is big in the middle,small on the both side.(2)Monitoring data show that the underground continuous wall is prone to produce uneven vertical displacement which will lead to the crack of underground continuous wall because of a large stress.he numerical model shows that the underground continuous wall has a tendency to rise,and is more uniform,and bottom heave have a main impact on vertical displacement of wall instead of the support style between the underground continuous wall.(3)The consequence can be drawn from the settlement rule of outside soil of foundation pit is that the precipitation is the main factor that causes the settlement of foundation pit outside the foundation pit in the high water level area.In the process of excavation,the pumping time and water quantity should be strictly controlled to ensure the settlement of foundation pit outside the safe range because of the settlement of foundation pit caused by the dewatering of foundation pit is more than 7times of the settlement of the surrounding soil mass caused by the excavation.(4)The Hen Qin foundation pit adjacent to the faith foundation pit.Theexcavation of the foundation pit is better than synchronous excavation,and the maximum deformation of the horizontal direction of the underground continuous wall caused by the synchronous excavation is 1.65 times of that caused by the non synchronous excavation through the establishment of three-dimensional numerical model and compare the three different excavation sequences adjacent to the foundation pit.From the model analysis can be seen,in order to ensure the safety of foundation pit construction,In the process of foundation pit construction,if the distance is in a certain range of mutual influence,the use of non synchronous excavation should be given priority in the construction process,so that the disturbance of soil between the foundation pit can be reduced to the minimum value.