Research On Optimization Of Supporting Structure Of Foundation Pit In Nanchang Civic Center

With the deep development of economy,the reform and development of urban industrial clusters have also entered the deep water area.Therefore,it is urgent to develop new cities to match the corresponding high-speed economic growth.Urban builders need to constantly improve urban buildings to adapt to the development of new cities,and the underground structure begins to receive more and more attention.The safety,economy and other factors of foundation pit engineering design directly affect whether the underground engineering is safe and stable and whether it has higher economic benefits.Therefore,how to design and construct,to ensure the safety and stability of the foundation pit in the process of excavation,while taking into account the requirements of economic benefits,has become an urgent problem to be solved.In order to discuss how to reduce the cost and improve the economic benefit under the premise of ensuring the safety in the actual project,this paper takes the foundation pit project of Nanchang civic center as an example,and uses the fuzzy comprehensive evaluation method to preliminarily determine four kinds of supporting schemes for the foundation pit project("reinforced cement wall+composite soil nail wall supporting scheme","underground continuous wall+internal support scheme","row supporting scheme" Pile wall+Anchor Pull support scheme "and" slope+row pile+soil nail wall support scheme ")are compared and selected.After the support scheme is determined,the safety of the support scheme is analyzed by FLAC3D finite difference numerical simulation platform.At the same time,the detailed parameters of the support structure(taking the distribution form of soil nail wall and the embedded depth of row pile as an example)are optimized.Finally,the original plum blossom type of soil nail is modified The arrangement scheme and the reduction of the embedded depth of the row piles by 1 m can improve the economic benefits on the premise that the safety is still guaranteed.It is found that the numerical simulation results are different from the actual test results,but the results are all safe,which verifies the feasibility of the support scheme.In the case of limited actual engineering conditions and difficult to arrange monitoring points,the safety of the project can be judged by numerical simulation in advance,and then combined with the construction dynamic monitoring,which can ensure the safety and stability of the foundation pit project in the excavation process.