基于混合设计的高性能钢梁抗弯性能及延性试验

Bending Behavior and Ductility Test of High Performance Steel Beam Based on Hybrid Design

基于混合设计的理念,采用中国产高性能钢HPS 485W和普通结构钢Q235,加工制造了6片混合设计工字形钢梁,在跨中单点加载,研究试验梁的抗弯承载能力、变形特征及最终的破坏形态。试验结果表明:腹板屈曲强度和试验梁侧向支撑刚度对试验梁的极限承载力、延性和失效形式有显著影响;试验梁的抗弯承载力主要由翼缘提供,但抗弯延性主要受腹板控制,承载力下降阶段受腹板屈曲强度影响显著;采用厚实截面设计的高性能钢梁可以达到全截面塑性,在有效的侧向限位下高性能钢梁具有很好的延性。试验结果与理论计算结果的对比表明,塑性弯矩理论计算结果与试验值吻合较好。

Based on the concept of hybrid design,6 I-beams were designed and fabricated by high performance steel HPS 485W for flanges and steel Q235 for webs.In the bending test,these simple supported welding beams were loaded at mid-span.After the test,flexural capacity,deformation characteristics and the ultimate failure mode were analyzed during the whole experimental process.Test results show that web bucking strength and the rigidity of lateral bracing significantly affect the ultimate capacity,ductility and failure mode of tested beams.Flexural capacity is mainly contributed by flanges,and ductility is primarily affected by web.The descending stage of the bending capacity is controlled by the web bucking strength.It can be concluded that HPS beam with compact section has good plastic bending behavior and good ductility under effective lateral bracing system.Comparison between test result and theoretical calculation shows good coincidence between theoretical plastic moment and bending process in the test.