Designation And Optimization Of Foundation Pit Support For Beiren Group Worker Apartment

The excavation and support of foundation pit is a systematic project. It consists of a variety of complicated factors, which are in mutual connection and restriction. It is not only related to a range of disciplines, soil science, soil mechanics, rock mechanics, structural mechanics, material mechanics, hydrogeology, in-situ testing techniques, and so on, but also is very common in our daily life, and it’s strength and deformation problems hardly affect people’s life and property safety. Foundation pit engineering and soil around the retaining structure is common when using force equilibrium process, therefore foundation pit engineering is a very important in the area of geotechnical engineering, but also has a strong comprehensive topic.In the foundation pit supporting engineering design, people should pay attention to the safety of the supporting plan, guarantee the stability of foundation pit surrounding environment,and should pay attention to the construction cost control in construction. In recent years, with the rapid development of cities, more and more deep excavations are developed, which are mostly located in the city center. These engineerings geological conditions are complex, and the projects are huge. The surrounding environmental conditions have a far-reaching influence with these projects. Both the project design and congstruct difficulty are increasing. The security and rationality of design are increasingly demanded. Once the design fails, incalculable huge losses will be caused and the process is very difficult.The common support forms of foundation in Beijing are summarized in this paper, and the various types of supporting computing theory and design methods are briefly described; The unearthed nail wall, gravity cement walls, pile, row pile, diaphragm walls, steel cement mixing walls and prestressed anchor are inducted, including different forms of support characteristics and scope. The main factors affecting the excavation program of choice are pointed out. How to optimize the excavation program and choose the most reasonable design and to ensure the safety and economy are particularly important.Currently, foundation pit design optimization can be basically divided into three levels,respectively are the optimization of excavation type, the support retaining structure design optimization, and the construction of information-oriented process. According to the Beiren Group Corporation Worker Apartment Project their own characteristic, this paper gives two supporting plans in the foundation pit supporting type choice, and then optimize the comparison;when optimizeing the supporting structure detail, it considers the formation conditions andconstruction machinery operation convenience and feasibility, and adopts the steel tube miniature pile instead of the large pile design; at last, through monitoring on the supporting structure and surrounding environment, it optimizes the modify design parameters timely in construction process, and has a targeted solution to the local large deformation problems.The staff residential building of Beiren Group Corporation is in the ambient conditions with different base depth, and the project is located in furukawa track, containing bad geological conditions, such as room muck, mucky soil, etc., which bring a certain degree of difficulty to the project design and construction of pit. In this paper, the excavation methods commonly used in Beijing area are summarized. Based on the fuzzy comprehensive evaluation method, two kinds of support programs, stake anchor bracing and composite soil nailing support are proposed initially. According to the project’s own characteristics, the different sections of pit are optimized,and the strengthen designation of the key and difficult parts of the excavation is carried out. In the project implementation process, the support structure is monitored to address the emergence of local surface cracks and excessive displacement issues. Practice has proved that the design and optimization of support not only ensure the security and stability of excavation, but also save the project cost, and achieve a win-win outcome for the future implementation of similar projects.It has certain practical significance to improve construction safety, speed up the construction schedule and reduce the project cost.