铝合金偏压构件高温下整体弯扭承载力研究

Study on Flexural-Torsional Behavior of Aluminum Alloy Members under Eccentric Compression at Elevated Temperatures

为研究铝合金偏压构件在高温下的整体弯扭稳定承载性能,完成了12根铝合金H型截面构件偏心受压稳定承载力试验,所有试件均发生弯扭失稳。采用ANSYS对试件进行数值模拟,有限元与试验结果在破坏形态和荷载-位移曲线上吻合良好。基于所建立的数值模型,对不同铝合金牌号、截面类型、截面规格和长细比的国产铝合金偏压构件进行了大规模参数分析,共得到532条相关曲线。根据试验和有限元结果,提出铝合金偏压构件高温下的弯扭稳定承载力计算公式,为铝合金偏压构件的抗火设计提供了依据。

Experiments on 12 H-shaped eccentrically compressed specimens under various temperatures were performed to explore the flexural-torsional stability of the aluminum alloy members,and all the specimens failed with flexural-torsional buckling. The specimens were simulated using ANSYS.The finite element(FE)and experimental results agreed well on the failure modes and load-displacement curves. Parametric study was carried out using the established FE model considering variation of aluminum alloy brands,slenderness,section types and specifications,through which 532 interaction curves were obtained. Finally,on the basis of the test and FE results,a formula for capacity calculation on flexural-torsional stability of aluminum alloy eccentrically compressed members under elevated temperatures was proposed,which provided a foundation for fire design of aluminum alloy members under eccentric compression.