考虑砂土密实度影响的沙漠管桩承载性能离散-连续耦合分析OA

Based on the problem that the bearing capacity of photovoltaic piles in desert areas exceeds the design re-quirements of the superstructure,the influence mechanism of sandy soil density on the development of soil plugs,soil deformation and piles resistance was systematically analyzed by the discrete element numerical simulation method and the discrete-continuous coupling model,and compared with the closed piles.The research results show that:1)The density of sandy soil significantly affects the pile driving response and the shear swelling effect is en-hanced in highly dense sandy soil to form the stable soil arch.2)The resistance of pile driving is dominated by ex-ternal frictional resistance,with concentrated shear zones around the piles and the passive arch development reach-ing a depth of 1.8 times the pile diameter.However,the soil arch structure is unstable and the resistance fluctuates significantly and the height of soil plug development is unstable in low-density sandy soil.3)The results of the lateral friction resistance of the open piles and closed piles show that the open piles significantly weaken the soil squeezing effect due to the soil plug effect,with the shear zone range reduced by approximately 40％,the passive arch depth decreased by 45％,and the pile driving resistance dropped by 40％.Moreover,the resistance composition changes from being dominated by end bearing to by lateral friction,revealing the reconstruction effect of the soil plug on the energy transfer path.This research provides a theoretical basis for the optimal design and construction control of photovoltaic pile foundations in desert areas.