Analysis For Compaction Effect Of Static Sinking-Pipe-Pile With Hole Based On Cavity Expansion Theory

With the rapid development of our country engineering construction, reasonable and effective reducing the effects of building construction engineering on the surrounding living environment, especially in the influence of the dense urban area,have become a very worth exploring and research important topic. As a result of pipe pile with a lot of advantages, for example good quality and low price, no noise, no vibration, no impact etc, It is widely used in practical engineering. Static pressure pipe pile belongs to the typical soil displacement pile. Many adverse impact is very obvious,and is caused on the surrounding of the adjacent buildings and structures in the process of pipe pile driving. In order to reduce static pressure pipe pile driving effect, many scholars put forward a variety of the treatment measures and the method of pipe pile construction changed. Based on the new technology of pipe pile with hole and used cavity expansion theory and the method of numerical simulation, soil compaction effect of the new type pipe-pile with hole, and the focus’ s excess pore water pressure, is detailedly researched and discussed in this article. Soil compaction effect of static pressure pipe pile without hole and pipe pile with hole is compared and analyzed. The technology of pipe pile with hole is proved that can effectively reduce the negative impact of soil compaction effect. The main research contents and achievements are as follows:(1)The situation of development and application of static pressure pipe pile is systematically summarized. The adverse impact of soil compaction effect on the surrounding environment caused by the static pressure pipe pile construction is analyzed.(2)Based on the Tresca and Mohr-Coulomb failure criterion of cavity expansion theory, the theoretical expression of the radial stress, the hoop stress and radial displacement distribution along the radial direction is derived. The theoretical solution of excess pore water pressure of static pressure pipe pile general is further improved,and the excess pore water pressure and the influence of poisson’s ratio is cleared.(3)Based on cavity expansion theory and the static pressure pipe pile without hole, introduced into reasonable parameters, general theoretical solution of excess pore water pressure of static pressure of pipe pile with hole is deduced. At the same time based on limit equilibrium principle, the expression of the maximum excess pore water pressure of static pressure pipe pile with hole is got. It is compared and analyzed that the maximum of excess pore water pressure of pipe pile with hole is less than the maximum of excess pore water pressure of pipe pile without hole during static pressure pipe pile process. It is Further proved that the static pressure pipe pile with hole is more advantageous to the dissipation of excess pore water pressure, and reached that pipe pile with hole can reduce the excess pore water pressure in certain degree.(4)Based on software FLAC3 D finite difference method, 3d dynamic numericalsimulation is used for expansion process of static pressure pipe pile with hole and pipe pile without hole. The distribution of excess pore water pressure of static pressure pipe pile with hole and pipe pile without hole is discussed. Pipe pile with hole technology is explained that the effect of the maximum of excess pore water pressure is reduced.Pipe pile with hole technology is further proved that the maximum of excess pore water pressure is reduced, and the adverse effects of soil compaction effect of static pressure pipe pile is effectively reduced.