The Reaserch On Supporting Protection Method Of Deep Foundation Pit

Foundation pit engineering mainly includes slope excavation and foundation pitsupporting system of choice, it is a comprehensive of systematical engineering. Andthe choice of the support method directly related to the safety of the engineeringpractical stability, economic usefulness and construction convenience, the increasingscarcity of land resources in the city today, the imminent development of undergroundspace, requirements are also increasing, which is based pit Bracing technicalrequirements have become increasingly stringent. In recent years, Collapse Accidentshave often occurred in the domestic, so for us, the exploration of the problem of howto improve the supporting technology is particularly important.The thesis mainly includes the following four aspects of content:The first part: the support theory as well as the development and research of thesupport method at home and abroad were summarized overview of the system;The second part: the current common supporting methods analyzed one by oneand explained through the chart, and they were compared unified summary;The third part: passing through the row piles supporting、 undergroundcontinuous wall supporting、soil nailing wall protection，that are three main ways tocontrol supporting methods and various design parameters optimization, and showshow to select the best design proposal. Among them, Row of piles selected designparameters include piles embedded depth、pile diameter selection、strength grade ofconcrete、steel support position; underground continuous wall supporting selecteddesign parameters include embedded depth of the wall、the wall thickness、the supportposition、soil nailing wall protection selected design parameters include soil nailingaperture、soil nailing horizontal spacing、vertical spacing of soil nails、soil nailingangle of incidence;The fourth part: using the actual project as an example, firstly, its use of thegrading excavation、Soil Nailing、Plus a pile of internal support within the method ofsupport. And then combining with the content of the third part to optimize the designparameters which were chosen, finally, selecting the SMW (new cement-soil mixingpile wall) of the foundation to support the foundation pit, in through comparing withthe results of the three supporting, including safety、 economy、 construction ofenvironmental protection, drawing a conclusion. It is including the following two aspects. Firstly, the design of the whole idea of the situation remains unchanged, bychanging the value part of the design parameters can be done to optimize the designof support so as to achieve the objective of reducing the costs. Secondly, through theanalysis of the instance of SMW supporting research, and to contrast other supportingmethod, then to prove its feasibility and applicability, thus carries on the promotion.