The Option And Optimization Of Solutions About Deep Foundation Pit Supporting Technique

Foundation pit engineering is an ancient geotechnical subject with time features; it’s the subject that experts and scholars are researching on to choose the reasonable design according to different geological conditions. with the increasing number of high-rise city construction, the foundation pits are more and more, the scale is bigger and bigger, the involved problems become more. facing varies structures, it’s still hard to select the best supporting structure and parameters to meet the actual require. In consideration of the safety and cost, more and more attention is paid by the engineering technical personnel on structure optimization. choosing the best design to ensure the pit’s safety, steady, economize and rationality, it also can produce economic efficiency, social efficiency and environment efficiency.The deep foundation pit engineering including design,construction, excavation, groundwater control, monitoring and the surrounding environment protection etc, it has a strong systematic. Including the strength, stability,deformation and so on, it’s a subject refers to the engineering geology, soil mechanics, basic engineering, structural mechanics, engineering structure, construction technology and other disciplines with strong technical and comprehensive. Moreover, the deep foundation pit has strong individual character and practice in the new era environment engineering related to many uncertainty and fuzziness factors, deep foundation pit engineering and presents many new features. especially for the deep foundation pit supporting structure, although it is a temporary building, it directly related to the whole project safety, schedule and cost. Therefore, the development of deep foundation pit engineering puts forward a higher requirement in supporting structure scheme and the design optimization.This paper mainly completed the following aspects:briefly introduce the characteristics of deep foundation pit engineering and its situation in and aboard, combining the characteristics of its support type, state the basic theory of supporting design, the calculation and design principle and so on, the optimum design theory is analyzed and discussed. The necessity and importance of design optimization for the deep foundation pit supporting are demonstrated. summarize the common foundation pit support type and its application conditions, and find out the suitable multi-objective optimization method for deep foundation pit engineering support, solve the problems involved in the foundation pit engineering design and construction, it has significance both in theoretical and practical to enhances the enterprise economic efficiency and the social efficiency. Point out the economic as the guiding ideology in selecting the best one among varies support structure. finally, combine the underground garage case in shang pin community, it discussed and optimized the selection of support design, the specific steps are as followed:(1) design support scheme as much as possible;(2) select the design;(3) compare the selected one;(4) get the final design after optimization. do the structure designs work on the selected scheme and propose the requirements on construction and quality control of the pit structure.