Study On Behavior Of Sloping Pipe-pile

Jacked pile is widely used because of its various advantages such as noiseless, vibrationless,no impact and minor construction stress. However, because of compacting effects caused by the penetration of jacked pile ,he may have severe influence on surrounding engineering environment. So it is important for engineering application that compacting effects of jacked pile are effectively predicted .The mainly analysis measure of the jacked pile that influence on the surrounding engineering environment is the cavity expansion theory and the numerical simulation. This articles,systemically summarize the calculation method of the cavity expansion theory, integrally expand the solution of the cylinder expansion problem which is based on the Mohr-coulomb yield criterion.Jacked pile driving process is a steady-state penetration process.Being different from the general construction of static problem,but also different from the piling and other power problems,it should highlight the prefabricated pile of penetration and soil compaction feature.The three methods can be used to simulate the pile driving:penetration force method,displacement penetration method,cavity expansion method.The follow work is done in this article:(1)The article describes the research background,summarizes the current research status on analysis of soil compactiong effect of jacked pile ,study and solve problems.(2) In this article, the finite element numerical simulation is used to analyse if displacement penetration method can reasonably analyse compacting effects by the jacked pile. Firstly , this article analyse the effects of displacement fields caused by different depths, pile diameter and modulus ratios of pile to soil.In the radial the maximum radial displacement is at 10d from pile;in the depth the maximum radial displacement occurs 4d under the pile tip;for vertical displacement ,surface soil mainly sinks;the larger the diameter pile,pile produces greater radial and vertical displacement;soil harder,surface soil occurs uplift.Then, the paper analyses lateral and vertical diaplacement field of double piles,three piles caused by driving.By finite analysis,for two-pile radialdisplacement and vertical displacement of first district are much smaller than the other two areas due to sheltering effects of existing pile;because of existing pile effect, radial displacement of second district is limited , vertical displacement increase;for three-pile, displacement law of first distric is same as two-pile; because of existing pile effect, radial displacement and vertical displacement of second district is much smaller third district's; displacement law of thirdt distric is same as second distric of two-pile.