Study On The Influence Of Lateral Limb Location And Arrangement On The Vertical Bearing Capacity Of SSP

With the development of the times and the continuous improvement of the national economy,the field of construction engineering has put forward new requirements for pile forms.In this paper,a new type of pile,side embedded steel pipe pile(SSP pile for short),derived from the traditional steel pipe pile foundation with constant section,is proposed.This is the insertion of side legs into the pile body on the traditional steel pipe pile foundation.By changing the shape of the pipe pile,the friction between the pile and the soil is increased,to improve the bearing capacity of the foundation.This article analyzes the influence of different lateral leg positions and arrangements on the bearing capacity of single embedded steel pipe piles under vertical loads through ABAQUS finite element simulation and small-scale half section model pile tests.Using ABAQUS finite element simulation software,simulate the vertical load of prototype piles with different side limb positions and arrangements.Through the load displacement curve,vertical displacement cloud map,and pile axis diagram in the simulation results,the bearing capacity of the pile was studied and analyzed.When the number and spacing of side limbs were the same,the bearing capacity of the side limbs arranged at the lower part of the pile was large.After changing the side limb arrangement method,there was a trend of decreasing the bearing capacity of the side limbs compared to the normal arrangement.When the lateral limb position is arranged at the lower part,the relative slip of the surrounding pile soil is small,so when the lateral limb position is arranged at the lower part,it can effectively improve the bearing capacity of the pile.The axial force of the pile decreases with increasing depth,and the axial force at the side legs undergoes a sudden change.The pile end is a curved straight line,indicating that the side legs have changed the stress situation and improved the bearing capacity of the pile.A test plan was developed in the experimental section,and indoor model tests were conducted on small scale half section model pile specimens with different side limb positions and side limb arrangements.The qualitative analysis results showed the failure and deformation characteristics of the soil around the side embedded steel pipe pile,and recorded the entire failure process of the pile body,Based on the changes in the bearing capacity of a single pile and the soil around the pile under vertical load for side embedded steel pipe piles with different side limb positions and arrangement methods,it is concluded that the side limb arrangement of the side embedded steel pipe pile is the most reasonable at the lower part of the pile body.By comparing and analyzing the ABAQUS finite element simulation results and experimental results of side embedded steel pipe piles,it was found that there is a significant similarity in the stress changes between the two.At the same time,it was found that the more side limbs are arranged in the lower part of the pile body,the greater the improvement of the vertical bearing capacity of the pile.Furthermore,a reasonable position and arrangement method of the side limbs were obtained,and a practical formula for calculating the vertical bearing capacity of side embedded steel pipe piles was derived.This article studies a new type of pile side embedded steel pipe pile.The bearing capacity of a single pile under vertical load is studied and analyzed using different side limb positions and arrangements,laying a theoretical foundation for practical applications,and providing certain reference value.