Supporting Design And Numerical Simulation On Deep Foundation Pit Engineering In Beijing

Deep foundation pit project is located in densely populated urban area,and its surrounding environment is complex.In the design,not only the stability of foundation pit support should meet the standards,but also the wall deformation,the bottom heave and the deformation of the surrounding soil should also meet the design requirements.The excavation of deep foundation pit has a strong environmental effect,and its influence on the surrounding roads,pipelines and buildings can not be underestimated.Therefore,it is very important to study the numerical simulation and deformation law of the foundation pit.Based on Lizheng 7.0 software,using GEO5(Finite element analysis software for geotechnical engineering)to the Beijing foundation pit excavation process simulation.Then,by comparing it with the field monitoring data,the reliability of the support scheme and the rationality of the numerical model are verified.The main research process of this paper is as follows:(1)On the north side of a deep foundation pit project in Beijing,by using LIZHENG7.0 the support design is carried on,and check its stability,the result conforms to the standard request.(2)The excavation process of the foundation pit is simulated by GEO5,and the deformation law of the foundation pit is analyzed.(3)The calculation results of Lizheng and the finite element analysis results are compared with the field monitoring results that including the horizontal displacement of pole top,deep horizontal displacement of pile body,the ground surface settlement,foundation pit heave amount,pile bending moment and shear force of pile.The reliability of the support scheme and the rationality of the model are verified.(4)By changing the pile spacing,the position and horizontal spacing of anchor cable,the influence rule of the arrangement of the support structure on the deformation of the foundation pit is analyzed.Through the support design and numerical simulation analysis of a deep foundation pit in Beijing,the experience of supporting design of foundation pit is accumulated,and it can be used to other project with similar conditions for reference.