Research On Stress Mechanism And Deformation Characteristics Of Sheet Pile Wall With Relieving Platform

It has become an inevitable trend to develop and utilize underground space in the downtown with land shortage under the developing national economy and the accelerating urbanization.Most of the excavation supporting works in the urban area have the characteristics of deep depth,certain requirements for the surrounding environmental protection,land shortage,and no red line of anchor cables,etc.While the traditional retaining structure has the defects of long construction period,high cost,and environmentally inefficiency.In order to solve the above-mentioned problems,a sheet pile supporting structure with a weighing machine(Relieving platform),namely sheet pile wall with relieving platform,is proposed.Already the sheet pile wall with relieving platform has developed for decades in China,yet the research on its stress mechanism and deformation characteristics are not mature,and not only that,this supporting type was not mentioned in the relevant codes of foundation pit design,which restricts the application of such retaining structure in excavation engineering.Based on the MIDAS GTS general commercial software,this paper simulates the model test of the sheet pile wall with relieving platform,and also investigating the working mechanism,mechanical features,deformation characteristics,and failure mode of it.The main control parameters affecting the characteristics of such supporting structure are studied,the design theory and calculation method are improved,the application of such supporting structure in excavation engineering is promoted,thus the construction will be preferably guided.The main research contents and conclusions of this paper are as follows:(1)Through thoroughly understanding and analysis of the research status at home and abroad,the existing problems of the retaining structure of the sheet pile wall with relieving platform are systematically sorted out and analyzed;(2)The MIDAS GTS general commercial software was used to simulate the model test of the sheet pile wall with relieving platform,and also verify the proposed numerical model,investigate the working mechanism,mechanical features,deformation characteristics,and failure mode of the wall;(3)The main control parameters affecting the supporting structure design of the sheet pile wall with relieving platform,such as the buried depth and the width of the relieving platform,the embedded depth of the supporting pile,the diffusion angle of the relieving platform,and the rigidity of the pile wall,were studied through numerical simulation;(4)A set of design and calculation theory of the sheet pile wall with relieving platform is proposed to guide the design and construction.