The Geotechnical Structure Model Test And Numerical Analysis Of Deep Foundation Inner Supporting And Pit Supporting Pile Within The Limited Width

Foundation pit excavation is a unloading process. With the increase of excavation depth,soil around the foundation pit of stress field and displacement will be changed. Foundation pit supporting structure At present, there are many people research the effects of the earth pressure of foundation supporting on retaining structure internal force and deformation of soil,but the remolded soil within the limited width of the vertical earth pressure distribution on the internal forces of the supporting structure and the effects of deformation of soil is very little.The project got the support of coal bed gas of Shanxi mutual funds(2012012003) and national natural science foundation of China(51408558). This paper study the vertical earth pressure distribution of indoor geotechnical experiment within limited width range by homemade. And the vertical earth pressure distribution is used for numerical simulation. At the same time,through the comparison analysis software FLAC3 D numerical difference software and the measured vertical earth pressure distribution on the effects of internal forces of the supporting piles and deformation of the soil. The results showed that:1)Within the limited width of the pseudo vertical acceleration of reconstituted clays is lower than the theoretical value of 9.8 N/kg, measured about 0.62 g;2) According to the similarity principle, building a indoor geotechnical experiment model slot. Testing the supporting pile body internal force and displacement of pile top level changes in the process of excavation.3)Using the measured pseudo acceleration, comparison and analysis the effect of the reconstituted vertical soil pressure and the theoretical calculation of the vertical earth pressure on the retaining pile internal force and displacement of soil. The result show that remolded soil pseudo vertical acceleration has a little effect on the pile bending moment, but the impacton the displacement of soil is larger;4)When the excavation depth is shallow, supporting pile bending moment basic is "S" shape curve. with the increase of excavation depth, Supporting pile bending moment increases,supporting pile bending moment is "C" shape distribution;5) The pile bending moment for active earth pressure effects is negative above excavation surface, pile bending moment are mainly positive under excavation surface. With the increase of excavation depth, the inflection point of pile bending moment are moving down;6)The embedded depth of deep foundation pit supporting pile has the certain limit effect to soil horizontal displacement and the global stability of foundation pit. It has an impact on soil and foundation pit within a certain scope.