焊接楔形波纹腹板工字钢梁整体稳定性能研究

Investigation in the stability of welded tapered I-beams with corrugated webs

建立焊接楔形波纹腹板工字钢简支梁在不等端弯矩作用下的平衡微分方程,并采用有限积分法编写程序求解,提出楔形波纹腹板工字钢简支梁在不等端弯矩作用下临界弯矩的建议公式。将拟合公式计算结果与ANSYS特征屈曲分析进行比较,表明ANSYS特征屈曲分析与弹性理论吻合较好。利用ANSYS特征屈曲分析,拟合得到楔形波纹腹板工字钢简支梁和悬臂梁在6种典型荷载工况(集中荷载和均布荷载分别作用于上翼缘、剪心、下翼缘)下弹性临界弯矩的实用设计公式。在此基础上,通过ANSYS弹塑性稳定分析提出并验证楔形波纹腹板H型钢梁弹塑性稳定极限承载能力计算公式。最后进行5根楔形波纹腹板工字钢悬臂梁在自由端上翼缘单点加载的整体稳定试验,并将试验结果与ANSYS弹塑性分析结果及实用设计公式的计算结果进行对比,验证ANSYS有限元分析的合理性以及实用设计公式的可靠性。

The elastic stability differential equations of simply supported welded tapered I-beams with corrugated webs under non-uniform moments are established, and a program is developed by the finite integral method to obtain numerical results. Based on the results, a recommended formula for the critical bending moment is proposed. The characteristic buckling analysis results using FE software ANSYS are compared with the ones obtained from the recommended formula, which proves that the characteristic buckling analysis results agree well with those from the elastic theory. FE characteristic buckling analysis was conducted and the practical design formulas for critical bending moments of simply supported and cantilever tapered I-beams with corrugated webs under six kinds of typical load case （ Concentrated and uniform loads applied at the top flange, shear center, and bottom flange of the beam） were derived. Based on these formulas, the design formula for the overall stability ultimate capacity of tapered I-beams with corrugated webs was proposed through ANSYS elastic-plastic stability analysis. At last, 5 stability tests of cantilever I-beams with corrugated webs under concentrated loads at the top flange of the free end were conducted. And the test results were compared with the results from FE elastic-plastic stability analysis and those calculated from the practical design formulas in this paper, which proved the validity of the results from FEA and reliability from the practical design formulas in this paper.