Of Deep Foundation Pit Supporting Structure Optimization Design Method Research

Nowdays deep excavation engineering is a hot point of geotechnical engineering, which is payed attention to by the people. And it is a difficult point of geotechnical engineering.The expense of deep excavation account for a large scale in the full cost of the engineering. Therefore, how to choose the right bracing type and rational design parameters is the key of deep excavation engineering.In this paper, the author base on the research of the actuality of type choosing on deep excavation bracing structure and bracing structure optimal design, proposing a road of optimization design toward deep excavation bracing structure: (1)primary scheme choose(obtain possible scheme volume) (2)optimization choose on possible scheme (get the best scheme) (3)optimization design on the best scheme. Muti-class fuzzy comprehensive judgement and multi-objective fuzzy decision making are applied to optimization choose on possible scheme. And that mathematical methods is introduced in detail. In order to examine the feasibility of two methods,type choose on a deep excavation engineering in Wuhan is operated . Satisfying results are obtained. A new method-Genetic Algorithm is applied to optimization design on the best scheme. And explained by GA applied to the soil nailing optimization design. Relevant example is given. It proved that it is necessary to do optimization design on deep excavation engineering. Optimization design can greatly reduce the cost of the excavation engineering.