高强铝合金压弯构件稳定承载力中欧规范对比

Comparison of Chinese code and Eurocode9 in calculating the stability bearing capacity of high strength aluminum alloy beam-columns

为获得高强铝合金压弯构件稳定性能及其承载力,对29根箱型截面与L型截面6082-T6型高强铝合金构件进行偏心受压稳定承载力试验,获得其失稳破坏特征、承载能力及变形性能.在有限元模型获得试验结果验证的基础上,分析了初始缺陷幅值、截面尺寸、正则化长细比、偏心方向及偏心率等参数对构件的稳定承载力影响及其规律.利用试验及有限元稳定承载力影响参数分析结果,对中国《铝合金结构设计规范》和欧洲规范Eurocode9中的相关计算方法进行验证与结果对比,并对中国《铝合金结构设计规范》中L型截面压弯稳定承载力计算方法进行补充.结果表明:本文有限元模型可以精确地预测铝合金偏压构件的稳定承载与变形性能;中国《铝合金结构设计规范》和欧洲规范计算公式可以用于6082-T6铝合金箱型和L型截面构件压弯构件稳定承载力计算,但都相对保守.

Experimental studies of 29 pin-ended beam-columns, including 13 box-type and 16 L-type sections, extruded from 6082-T6 aluminum alloy, were performed in this paper to investigate the stability behavior and bearing capacity for high strength aluminum alloy. The buckling behavior, stability bearing capacity and deformation performance of all the specimens were obtained. A finite element （ FE） model of aluminum alloy beam-column was conducted by analysis software ABAQUS and verified by experimental results of 29 beam-columns. Initial geometric imperfection which influenced simulation results was analyzed. A parametric study of beam-columns with different cross section dimension, regularized slenderness ratio, eccentric direction and eccentricity ratio, was performed using the FE model. Finally, Chinese code and Eurocode9 were verified and compared by the experimental data and the results of the parametric study. Meanwhile the design approach based on Chinese code for L-type cross section beam-columns was proposed. It can be concluded that the FE model proposed in this paper can well predict the stability bearing capacity and the deformation characteristic for aluminum alloy beam-columns; Chinese code and Eurocode9 can be applied to doubly symmetric box-type cross section and mono-symmetrical L-type cross section beam-columns, but they were both too conservative.