Research On The Application Of Oblique Support System In Deep Silt Area Foundation Excavation

After decades of production and construction,the building density of the Pearl River Delta urban agglomeration is increasing,and the underground pipeline facilities are becoming more and more complex.As a result,more and more deep foundation excavation projects have to abandon the traditional pile-anchor support system when considering the form of support.And oblique support system because of its flexible layout,its use is not limited by surrounding building foundations and underground pipelines,and there is no disturbance to surrounding soil in the construction process,so it is favored by more and more engineers.In addition,when combined with the basin excavation construction scheme,the oblique support system can have a higher excavation rate and reduce the influence of time effect on the foundation excavation.Moreover,the oblique support system can provide a larger working surface and construction space for the basement construction,which has a high application value in the construction of deep foundation excavation engineering:This paper mainly studies the oblique support system,and carries out the following work:(1)Summarize the research status of deep foundation excavation engineering and the related theories of supporting design,summarize the supporting forms and application scope of deep foundation excavation in detail,and systematically introduce the finite element software MIDAS GTS NX used in numerical simulation in this paper.(2)Using MIDAS GTS NX finite element analysis software,a numerical model of a deep foundation excavation project in Foshan City is established.The feasibility of using numerical simulation method to study foundation excavation project is verified by comparing the calculated results with the monitoring data.It also shows that the model is more reasonable and the parameters are selected more accurately.At the same time,the calculation results are analyzed,and the variation laws of ground settlement,bottom heave and horizontal displacement of piles in numerical simulation are summarized,and the force of oblique support is described.(3)Using MIDAS GTS NX finite element analysis software,the single factor analysis of the deep silt foundation excavation is carried out.This paper mainly analyses the influence of the thickness of silt soil layer,the width and depth of soil reinforcement in passive zone,the inclination angle and spacing of oblique support on the deformation of foundation excavation and the stress of oblique support system,and draws some conclusions,which provide theoretical basis and guidance for the application of oblique support system in deep silt area foundation excavation.