三角形空翼缘梁的极限承载力试验研究

在澳大利亚学者提出的空翼缘梁(HFB)的基础上,提出一种新型三角形空翼缘梁(THFB)。通过试验测试,对三角形空翼缘梁(THFB)和传统H型钢梁在承受集中荷载作用下的破坏过程进行了对比,发现两种梁的破坏模态存在明显差异,THFB在集中荷载作用下极易发生局部屈曲,传统H型钢梁则易发生整体失稳,且THFB比传统H型钢梁具有较好的抗弯扭性能。利用有限元软件ANSYS对试验试件进行有限元模拟,试验结果和有限元模拟结果吻合较好。基于所建的有限元模型对THFB进行参数分析,参数主要包括上翼缘板厚、上翼缘板宽、腹板厚和钢材屈服强度,得出了THFB梁的承载力随不同参数的变化规律。最后结合理论和有限元分析,验证了Eurocode 3提供的H型钢梁设计公式计算THFB极限承载力的适用性。研究结果表明:采用Eurocode 3提供的H型钢梁设计公式对THFB的极限承载力进行验算是安全的,但偏于保守。

Experimental Analysis of Bearing Capacity of Triangle Hollow Flange Beam

On the basis of Hollow Flange Beam (HFB) which is proposed by Australian researchers, a new pattern triangle hollow flange beam (THFB) is presented. According to the experimental test and finite element simulation, the failure processes of THFB and traditional I-beam under concentrated load are compared, and then the obvious differences between the failure modes of these two type beams are founded. The local buckling is easily occurred for the THFB, while overall instability is easily occurred for traditional I-beam, and THFB possesses have better bending performance and twist resistance than those of traditional I-beam. with the experiments, finite element analysis is carried out by FE software ANSYS, and the FE results agree with the test results. Based on FE models, the parameter analysis is carried out for THFB. The parameters mainly include the thickness of top flange, the width of top flange, the thickness of web and the yield strength of steel. The change rule of the bearing capacity of THFB with different parameters can be achieved by parameter analysis. Finally, based on the above results, the applicability of the calculation formula of Eurocode3 to compute the bearing capacity of THFB is discussed. The results show that it is safe and reliable to adopt the calculation formula of Eurocode3 to compute the bearing capacity of THFB, Whilst the estimation is relatively conservative.