Numerical Simulation Analysis Of A New Type Of Multi-Supported Pile And Its Pullout Resistance

The new multi-supported pile is a special tool for extruding a semi-cylindrical dimple on the borehole wall,placing the steel cage and pouring concrete,that is,forming a support on the outside of the pile.The difference between the pile and the existing ordinary pile is that a semi-cylindrical support of a certain thickness is provided at regular intervals along the surface of the pile.In order to study the pull-out characteristics of the pile,numerical simulation analysis was carried out on the pull-out force,displacement,side friction resistance and load transfer law.(1)A cavity-forming tool and a new multi-supported pile prepared by a cavity-forming tool are given.(2)Using FLAC3D numerical analysis software,the influence of different bearing depth,support thickness and bearing spacing on the pullout resistance of the new multi-supported piles was studied.A total of 17 sets of comparative models were designed,and the optimal bearing depth was 0.50D,the support thickness was 0.375D,and the support spacing was 2.125D(D is the pile diameter).according to the uplift displacement and ultimate bearing capacity of the pile.(3)Under the conditions of optimal bearing depth,bearing thickness and bearing spacing,the simulated pile length is 15m,the pile diameter is 0.8m,the support depth is 0.4m,the support thickness is 0.3m,and the bearing spacing is 1.7m.The pull-out force of the new multi-supported pile is increased by 110%compared with the ordinary equal-section pile.(4)Numerical simulation study on the bearing capacity of the new multi-support piles under the optimal conditions,such as the pullout force,displacement,pile side friction resistance and the load transfer law of the pile body,is compared with ordinary equal section piles.Figure[34]table[12]reference[51]...