Study On The Optimization And Application Of Foundation Pit Support Schemes Under Complex Environmental Conditions

Since 2013,China’s economy has entered a new normal stage of high-quality development from rapid growth.The rapid development of the construction industry and the continuous increase in urban density have led to increasingly tight construction land.New construction projects are strictly restricted by the complex environment,and foundation pit projects are facing severe challenges.As a temporary structure,the foundation pit support project has the function of controlling the surrounding soil,ensuring earth excavation and the stability of the surrounding environment.Choosing a reasonable foundation pit support method will directly affect the foundation pit support structure itself and the surrounding buildings.Safety.Based on different regional conditions,the optimization of foundation pit support schemes is often based on experience,and there is a lack of a scientific and reasonable optimization system for foundation pit support schemes.Therefore,this article takes a certain science and education building project in Changsha City as the research object,and conducts the following research on the construction o f the optimal evaluation model of the foundation pit support scheme in the complex environment:First of all,after consulting a large number of domestic and foreign documents related to foundation pit engineering,the typical complex environment of foundation pit engineering is analyzed,and the methods of excavation and support of foundation pit are listed.There is a foundation pit support evaluation method,which discusses the regional adaptability of different foundation pit support schemes and evaluation methods,and lays a theoretical foundation for the follow-up study of the optimal evaluation model of foundation pit support schemes.Secondly,based on the analysis of the basic conditions,geological conditions,and construction difficulties of a science and education building project in Changsha City,a preliminary selection of complex environment foundation pit support from four aspects: safety and reliability,technical feasibility,economic rationality,and environmental impact The evaluation index for the optimization of the scheme.Based on the SMART principle and the gray correlation model,the secondary screening was performed from a qualitative and quantitative perspective,and the effectiveness and reliability of the evaluation index were analyzed,and the final evaluation index system for the optimal selection of foundation pit support schemes in complex environments was determined,and the evaluation was constructed for the follow-up evaluation.The model laid the foundation.Thirdly,based on the comprehensive analysis of foundation pit support and evaluation methods,the use of analytic hierarchy process,entropy weight method,and improved game theory combination weighting method to weight the preferred evaluation indicators of foundation pit support schemes,and use cloud model theory An evaluation model for the optimization of foundation pit support schemes in complex environments is constructed.Finally,combined with a science and education building project in Changsha City,an empirical study was carried out on the evaluation model of the complex environment foundation pit support plan.According to the design process of the foundation pit support plan,three types of complex environment foundation pit support plan were initially drawn up.By using the evaluation methods selected in Chapter 4 to calculate the subjective and objective and combined weights of the evaluation indicators,the comprehensive evaluation cloud model of each support plan is obtained by using matlab software programming.Through the comparison chart with the standard cloud,it is found that the comprehensive evaluation cloud model of Option 3 is closer to good.In order to ensure the safe implementation of the foundation pit support scheme in a complex environment,multiple monitoring points have been arranged around the foundation pit.Research shows that in the complex environment of soft soil area and adjacent to buildings,using the improved game theory-cloud model to optimize the foundation pit support plan is conducive to improving the efficiency of project management and providing scientific feasibility for the development of high-quality construction of similar projects Sexual reference.