Research On Foundation Pit Design And Numerical Simulation Of Hongda Pearl Project In Jilin

In recent decades,the urbanization process in our country is advancing,high-rise and super high-rise buildings,subway station,open trench tunnel,commercial parking lot,municipal plaza,bridge foundation,etc all kinds of large-scale engineering is increasing,scale of underground space development is more and more big,all of that has greatly promoted the rapid development of the foundation pit engineering theory and technology level.At present,people began to put their focus on how to achieve both social and environmental benefits under the premise of ensuring safety of pit foundation.Therefore,it is very important to choose logical deep foundation pit support method and design.In this paper,the optimal design of supporting structure is carried out by taking Hongda Pearl foundation pit project as the research object.The engineering design for foundation pit contraposes the engineering characteristics and surrounding environment conditions of foundation pit,and its support scheme including soil nail wall,prestressed anchor cable slope protection,soil nailing wall and prestressed anchor cable + + miniature pile,soil nailing wall of prestressed anchor pile + three support scheme.The main tasks are as follows:(1)It introduces the research status of foundation pit engineering at home and abroad,and summarize the theoretical foundation of common foundation pit design.Using principle is based on practical engineering condition in deep foundation pit software calculation method(specification)for analysis and design,and based on the calculation results to support scheme optimization design.It can meet that requirement of engineer safety,and can effectively reduce the construction cost.(2)The design scheme is numerically simulated by using the MIDAS/ GTS NX finite element software numerical simulation method.Taking the typical section has carried on the preliminary optimization,this paper simulated the conditions of displacement and stress changes under different excavation.The change characteristics of excavation process of foundation pit are analyzed by means of displacement and stress.(3)Through the comparison and analysis of the monitoring data and the numerical simulation results,the displacement of the envelope structure and the change trend of the forces are in accordance with the actual situation;The maximum difference of the horizontal displacement of surface soil is 12.5%,and the simulated numerical value and monitoring data are different.But the general trend is the same,indicating that the simulation results are in line with the actual engineering situation.Through numerical analysis,it shows that the palisade structure scheme security reserve is larger and slightly conservative,the design in the pile,soil nail and anchor rope design parameters can be further optimized,in order to achieve the safety and reliability of the project,and the optimal economic benefit.The scheme and numerical simulation results are useful for the foundation pit support of similar projects.