Research On Structural Stability Of Telescopic Boom Of All-Terrain Crane With Pit Defects

As various large-scale projects are being constructed around the world,AllTerrain Cranes are becoming more and more frequent in the public’s view.This is accompanied by increasingly higher performance requirements for the lifting height,lifting weight,operating radius and other performance indicators of AllTerrain Cranes.As one of the most important bearing components of All-Terrain Cranes,the telescopic boom has become increasingly heavier and the overall structure has become slenderer in order to adapt to increasingly complex engineering environments.As a result,the stability problem of the telescopic boom has become more and more prominent.At the same time,because there is no absolutely ideal and perfect structure under actual production conditions,various defects including pit defects will appear in the production,manufacturing,transportation,installation,and lifting service processes,which will have a very important impact on the bearing capacity and stability of the boom structure.Based on the previous research,the idea of Single Perturbation Load Approach(SPLA)and Multiple Perturbation Load Approach(MPLA)of buckling analysis of thin-walled cylindrical shell structure is introduced in this thesis,and pit defects are incorporated into the stability analysis of All-Terrain Crane telescopic boom structure,and a model of the boom structure with pit defects is established.By combining Python with ABAQUS,the influence of pit defects on boom stability is analyzed.The main research contents of this thesis are as follows:(1)The research object was the U-shaped telescopic boom of all-terrain crane and its finite element model was constructed using ABAQUS software for finite element analysis.(2)Write a script file using Python to create single point pit defects with different geometric parameters on the boom model.Perform nonlinear buckling analysis on them using ABAQUS,draw the relationship curve between different geometric parameters and weakening degree of single point pit defects,and obtain the law of arm stability affected by different geometric parameters.(3)Establish a model of the boom with different numbers and combinations of pit defects,and use ABAQUS to perform nonlinear buckling analysis on it,draw the curve of the weakening degree of multi-point pit defects on the critical buckling load of the boom with the number and combination of pit defects,and obtain the influence relationship of multi-point pit defects with different numbers and combinations on the critical buckling load of the boom,and compare it with the conclusion of single-point pit defects.