Comprehensive Analysis On Safety And Cost Of A Deep Base Pit Project

Deep foundation pit engineering is a complex and huge system engineering,which should not only ensure the safety and reliability,but also control the cost and cost of the project to ensure the economical and reasonable supporting system.In order to effectively coordinate the relationship between structural safety and cost economy,the optimization design of the supporting technology,the security reliability analysis of supporting system,and the effective control of cost and cost have become important issues for construction engineering and geoatechnical engineering.Taking Hangzhou HZ deep foundation pit supporting engineering as an example,the detailed analysis of the foundation pit supporting project summary,rock and soil layer characteristics,on the basis of the hydrogeological conditions,this paper discusses the SWM method + reinforced cement-soil pile anchor support plan process and retaining system security control methods,and use fuzzy comprehensive evaluation method is objective and scientific evaluation of solution to the safe and reliable performance.In the process of technical solution cost efficiency analysis,this article from the perspective of the construction unit system to study the engineering design,bidding,construction and completion settlement at various stages of construction cost control method,finally analysis the SWM method + reinforced cement-soil pile anchor support scheme and three axis the cement mixing pile + mud stop water heavy curtain wall inside the hole filling pile + support plan of two different capital cost,time limit for a project.The research shows that the maximum membership of the safety reliability level of SWM construction method + reinforced soil-cement pile anchor support scheme is 0.52,and the safety reliability belongs to grade B.In terms of technical safety,the support system can be guaranteed to be in the basic stable state,and other measures to improve the safety level of foundation pit can not be taken.The evaluation results are in good agreement with the actual monitoring status of foundation pit.The fuzzy evaluation theory has strong feasibility and accuracy in the analysis of safety reliability of deep foundation pit support system.Relative to the three axis the cement mixing pile + mud stop water heavy curtain wall inside the hole filling pile + support bolting system scheme,SWM method + reinforced cement-soil pile anchor support scheme can save design budgetary estimate of about 8.959 million yuan,and reducing the material input-23.72%,this scheme can significantly reduce the engineering cost,has the good economic effect,and is helpful to reduce the time limit for a project to ensure project completed on time.In other similar projects,the foundation pit supporting technology has certain value and application prospect.