Analysis On The Stability And Line-breaking Safety Of Long Span Prestressed Steel Arch Truss Dry Coal Shed

The prestressed steel arch truss has its unique advantages,such as good mechanical performance and light self-weight,which can meet the requirements of building modeling.This paper takes the long-span prestressed steel arch truss dry coal shed of a thermal power plant as the background project,the static performance,stability and cable breaking of prestressed steel arch truss are studied by using the finite element analysis software MIDAS GEN.In this paper,the structural form of dry coal shed is firstly selected.Three structural forms of dry coal shed,such as net truss,net shell and prestressed steel arch truss,are compared and analyzed.After that,the influence of the number of bracing bars,mid-span thickness,upper chord width and prestress value of cable on the static behavior of prestressed steel arch truss dry coal shed is considered,and the relevant conclusions are drawn.Secondly,the stability of prestressed steel arch truss structure was studied,the influence of different load combinations on the eigenvalue buckling analysis of the structure was studied,and the rationality of eigenvalue buckling analysis under the standard load combination was verified.Under the action of standard load combination,the influence of maximum initial defect value,mid-span thickness and number of bracing bars on the geometric nonlinear stability of prestressed steel arch truss was studied and analyzed.The increase of mid-span thickness can enhance the stability of the prestressed steel arch truss dry coal shed,and the amount of steel used in the structure will also increase.The existence of strut can enhance the stability of prestressed steel arch truss dry coal shed,but more is not better.Finally,an analysis is made on the accidental cable breaking of the prestressed steel arch truss in the dry coal shed,the results show that when the inhaul cable near the end of the prestressed steel arch truss breaks,the stress of the truss members peaks.The stress peak of the inhaul cable appears near the fractured inhaul cable,and the impact of the inhaul cable on the stress of the inhaul cable at both ends is very small when the cable is fractured in the middle of the dry coal shed.The increase of the cross-sectional area of the inhaul cable can reduce the vertical displacement of the structure,the stress of the truss members and the stress of the inhaul cable,it is beneficial to improve the static behavior of prestressed steel arch truss after inhaul cable breaking,then the collapse resistance of steel arch truss structure is analyzed and the related conclusions are obtained.