Inelastic Buckling Of Parallel Beam System Supported Each Other By The Torsional Bracing

As the good mechanical properties, the parallel beam system supported each otherby the torsional bracing is favorably applied in engineering. The girders of the parallelbeam system welded with three plates and connected to each other by the crossbeamcan work together under loads. Now the method of equivalent continuous stiffness iswidely used to design the parallel beam system in abroad. However the differentcomputing methods of equivalent continuous stiffness provided by the various designspecifications lead to the different design results. This phenomenon has aroused theconcern of many scholars.This paper performs a series of increment nonlinear analyses by using FEM. Thereliability of the FEM model is verified by quoting the experimental data did by theHanbat National University and the Pusan National University. Based on the reliableFEM model, this paper performs a series of numerical analyses and discovers that thestructure-load mode, the height of the crossbeam and the crossbeam spacing, the girderspacing have an effect on the lateral-torsional buckling strength. Compared with theuniform bending, the ultimate moment of the parallel beam system under theconcentrated load is bigger. With increasing of the crossbeam’s height, the ultimatecapacity increases gradually until stability; otherwise, reducing the crossbeam spacingcould significantly improve the ultimate capacity. The ultimate capacity of the parallelbeam system reaches the extreme points provided adopting the optimal spacing of theI-girders. The transverse web stiffener mainly prevents the web distortional behavior;the influence of the moment inertia of transverse web stiffener is not significantlycompared with other factors provided meeting the requirements.Discuss the design specification and the related articles by comparing the FEM data with the results calculated by related articles.