Study On Stability Performance And Design Method Of Double-braced Steel Derrick

Steel derrick is an important structure of mine hoisting system.At present,there are few studies on the stability and post-buckling strength of such structures.Therefore,in this paper,based on the background of a double-braced steel derrick with box section,the stability performance of this type of structure is studied.The specific contents are as follows.Based on ABAQUS,the shell element model of a box-section double-braced steel derrick is established.Considering the initial imperfections of the whole structure and members,the force,deformation and buckling of the original structure are analyzed by direct analysis method.The force,displacement characteristics and weak parts of the structure under various working conditions are studied.In the absence of longitudinal stiffeners,considering the post-buckling strength of the plate,the cross-section design of the original structure is carried out,and the force analysis of the redesigned structure is carried out.The results show that when the steel derrick meets the horizontal displacement requirement under working load by designing a larger cross-section size,the post-buckling strength of slabs can be used to meet the structural load-bearing requirements.This method can reduce the use of longitudinal stiffeners to reduce construction costs.Comparing with ordinary right-angle frame columns and tilted frame columns,the factors affecting the effective length factor of the braced columns are obtained.These factors include the stiffness ratio of the beam to the column,the inclination angle of the braced columns,the height of the braced columns and the length of the cross beam.On this basis,ABAQUS is used to calculate the effective length factor of braced columns in common intervals.The results show that the effective length factor increases with the increase of the inclination angle of the column,increases with the increase of the length of the beam,and decreases with the increase of the height of the column.Finally,the finite element results are plotted in tables for future engineering and design.