The Structure Design And Optimization Research On Trough Type Diaphragm Wall In Changchun

With the increasing development of urban construction, the city’s building density isincreasing, how to create more use of space in a limited plane has been the majorityconcern of the people, except for expanding higher space，the utilization of theunderground is more and more important. Changchun Central Hospital expansionproject is the first project using top-down method trough type diaphragm wall inChangchun region，it is a landmark of the Pit engineering design and construction inthe Changchun region。Thus this article can give some guidance and reference to theresearch of the design in future in Changchun region.Firstly, by analyzing the depth of the pit、the around environmental restrictions、thecontrast of the support deeper analyzing to the method of trough type diaphragm wallas support and waterproof structure in Changchun Central Hospital expansion project.This article use FLAC3D numerical simulation contrast with the method of thecalculation in the norm, and refering to the limit of permit to show the justifiability ofthe result., then show the better forecast of the horition displacement of trough typediaphragm wall by using FLAC3D numerical simulation.Through analyzing the two limit states of underground continuous wall, including thecalculation of the ultimate bearing state and normal state, we know the ultimate limitstate has no effect on the structural design of underground continuous wall, normalstate is the control factors of the structural design of underground continuous wall.And adjusted the permit maximum crack width limits (increased to0.3mm),inreference to the instance of the expansion project of the Central Hospital ofChangchun, to do the optimization design of the trough type diaphragm wall in Changchun. Through adjusting the permit maximum crack width limits, deeperanalyzing the optimization design of structure using the factor of the thickness of thewall、the effect of the reinforced strength and the area。Through the contrast，we getthe suit design project of deeper than four underground in the Changchun region，theoptimized program can be increased to a maximum of22%according to actualengineering, and the reinforced area can reduce to25%, while the volume of theconcrete only75%of the actual project.