Numerical Simulation Analysis Of Bolt Support Structure Based On ABAQUS

The continuous advancement in the field of construction engineering in recent years has put more and more design requirements for foundation pit support.However,in-depth research is needed as deep foundation pit accidents often occur due to improper support structure design.In this dissertation,based on the deep foundation pit project,a pile anchor support structure was selected as the subject of study and the basic theory of pile anchor support structure was analyzed.Based on the design and calculation of the foundation pit using rationalization software,ABAQUS finite element software was used to perform numerical simulation analysis of the excavation and support of the foundation pit.First,we studied the trend of changes in horizontal displacement of the side walls of the foundation pit,the amount of ground settlement,and the change in the elevation of the pit floor under various working conditions.Finally,we further optimized the design approach to obtain reliable parameter values through comparative analysis of the law of deformation of the foundation fit.The deformation of the foundation pit can be more effectively controlled to increase the supporting effect.The results show that: Firstly,for this project,when using pile anchors for foundation pit support,when the excavation depth of the foundation pit reaches 15 m,anchor angle should be 25 °.At this time,the horizontal displacement of the side walls of the foundation pit is relatively smaller than when the anchor angle is 15 °.In addition,the pit bottom soil has relatively little ridge deformation and the best support effect;Secondly,the anchor prestress can significantly reduce the deformation of the foundation pit.When the prestress value is 500 k N,the range of subsidence deformation of the foundation pit shows a relatively obvious contraction.The range of soil uplift deformation at the bottom of the pit also decreases accordingly,and the horizontal displacement of the sidewalls of the foundation pit can be better controlled;Thirdly,by adjusting the horizontal distance of the anchor rod,the horizontal displacement and ground subsidence values of the side walls of the foundation pit can also be reduced.After excavating the foundation pit to 15 m,the effect became more evident when the horizontal distance between the anchor rods was 2.3m.At the initial stage of excavation of the foundation pit,changes in the displacement of the foundation pit are roughly reflected in the elevation and deformation of the soil at the bottom of the pit,the horizontal displacement of the side walls of the foundation pit,the settlement and deformation of the surface of the foundation pit.Displacement during excavation is proportional to the depth of the foundation pit and is within the allowable range of specifications,it basically matches the actual monitoring data;If the excavation depth is more than 15.0m and after adjustment of the pile anchor support parameters,the deformation of the foundation pit has changed significantly,and attention should be paid to the deformation of the foundation pit.