梭形柱的稳定性能及设计方法研究

梭形柱由于其优美的建筑造型,近年来作为竖向受力构件广泛应用于各类空间结构体系。首先介绍梭形柱的工程应用及受力特点,研究梭形实腹柱和梭形格构柱的稳定承载力和破坏机理,提出整体稳定承载力的计算和设计方法。研究成果表明,由于梭形柱的截面形态各异,惯性矩沿轴线的函数关系复杂,其屈曲模态及稳定承载力的设计理论与等截面柱有很大区别。梭形实腹柱可以等效成等截面柱验算其稳定承载力,其计算长度及等效长细比与楔率和截面的最大、最小惯性矩有关,其屈曲波形始终表现为单波形;格构式梭形柱由于剪切刚度和弯曲刚度沿柱轴线是变化的,导致了梭形格构柱的屈曲波形出现了反对称的“S”形波形的可能性。

STABILITY BEHAVIOR AND DESIGN OF LONGITUDINAL SHUTTLE-SHAPED COLUMN

The longitudinal shuttle-shaped columns,as a new type of structural member loaded axially,have been extended into many public buildings recently because of their special and beautiful appearance.Which may be classified into a solid-web section shuttle-shaped column and a build-up section shuttle-shaped column.The latter is called generally as shuttle-shape latticed column formed by longitudinal steel tubes behaving as branches and horizontals steel tubes behaving as batten plates. Instability behavior and design method of both solid-web section shuttleshaped column and shuttle-shape latticed column are presented.The material and geometric nonlinear FE analysis program(ANSYS) is employed to investigate theoretically the influence of the geometric parameters on the buckling behavior and failure mechanism of both columns.These geometric parameters include column length,column slenderness ratio,single branch tube slenderness ratio,the number of diaphragms and thickness of diaphragms tube.By varying these parameters mentioned above the elastic buckling load and corresponding buckling mode of SLC are investigated respectively.And an ultimate strength of SLC is studied and concluded finally.A new and interesting failure mechanism is found from the numerical results obtained and a useful design method for checking overall instability is drawn for practical project design.