Design Of Supporting Structure For Deep Foundation Pit Based On Deformation Control

The calculation of the soil pressure in the design of deep foundation pit is carried out by using Rankine’s soil pressure calculation theory.However,the structure around the deep foundation pit is more sensitive to the displacement change of the supporting structure.Therefore,in the design of foundation pit,the control of displacement is of great engineering significance to the support structure design of deep foundation pit In this paper,a foundation pit project in wuxi is taken as the research object of design.Considering the influence of displacement and water content on earth pressure,the supporting structure of a foundation pit project in wuxi is designed based on deformation control.Based on laboratory tests,the effects of displacement and water content on the mechanical parameters of soil are studied.The results show that when the moisture content is constant,the effect of displacement and water content on the mechanical parameters of soil has been studied.The mechanical parameters(cohesion and internal friction angle)of soil increase with the increase of displacement,which can be expressed as c=aln(s)+b,φ=mln(s)+n.when the displacement is constant,the internal friction angle of soil mechanical parameters decreases with the increase of moisture content,and the cohesion increases with the increase of moisture content,which can represent the relationship of forming such as c=dln(co)+f,φ=tln(co)+z.The relationship between mechanical parameters and displacement and moisture content is studied by experimental analysis,and the influence of displacement and moisture content on earth pressure is studied by combining Rankine earth pressure calculation formula.The results show that:(1)the relationship between mechanical parameters(cohesion and internal friction angle)and displacement of soil can be expressed as the relationship of forming such as c=aln(s)+b,φ=mln(s)+n;The relationship between soil mechanical parameters(cohesion and internal friction angle)and water content can be expressed as the relationship of forming such as c=dln(co)+f,φ=tln(ω)+z;(2)when the soil sample is saturated with 21%moisture content,the active soil pressure is related to the soil moisture content The displacement relationship can be expressed as ea=-50.321n(s)+298.04,and when the displacement S=3/4Smax is controlled,the relationship between active earth pressure and moisture content can be expressed as ea=ea=-42.71n(ω)+41.18..According to the results of the above research,the mechanical parameters(cohesion and internal friction angle)are modified According to the modified results,the maximum shear force is 177.611kN and the maximum bending moment is 315.81kN·m.The maximum shear force value is 121.46kN and the maximum bending moment value is 254.23kN·m.The results show that the shear force and bending moment value calculated by the straightening software is smaller than the manual value,and the maximum shear force value and the maximum bending moment value are 254.23kN·m.The results show that the shear force and bending moment value calculated by the correction software is smaller than the manual value.The displacement,shear force and bending moment of the design results are compared and calculated by using Qimingxing software and Lizheng software.The results show that the values of displacement,shear force and bending moment calculated by the software are smaller than those calculated by the software.Considering the displacement factor,the calculation result of correction software is safer,while the calculation result of bending moment factor is more safe when considering shear force.The research results can be used for reference in the design of the same type of foundation pit supporting structure.Figure [70] Table [36] Referencess [62]...