高强度工字钢梁抗弯性能试验  

Flexural behavior test of high strength steel I beam

作　　者：段兰[1] 张亮[1] 王春生[1] 郑丽[1] 

机构地区：[1]长安大学桥梁与隧道陕西省重点实验室,陕西西安710064

出　　处：《长安大学学报（自然科学版）》2012年第6期52-58,共7页Journal of Chang’an University(Natural Science Edition)

基　　金：教育部新世纪优秀人才支持计划资助项目(NCET-07-0121);交通运输部西部交通建设科技项目(2011 318 494 890)

摘　　要：为了研究高强度工字钢梁的抗弯性能和延性,基于混合设计的理念,采用中国产高强度、高性能钢HPS485W(名义屈服强度为485 MPa)和传统钢种Q345,设计并加工了3片简支工字钢梁,在跨中加载对试验梁进行抗弯试验。试验后分析试验梁的应力变化、变形特征、破坏形态及承载能力。分析结果表明:在有效的侧向约束下,高强度钢梁最终破坏时跨中均形成塑性铰,试验梁的最终破坏形态均为跨中附近受压翼缘和受压区腹板的局部屈曲;对于混合设计的高强度钢梁,翼缘和腹板材料有合理的强度匹配范围,当采用强度较高的HPS485W翼缘时,建议腹板钢材强度的选取不低于Q345;翼缘的尺寸效应是影响试验梁抗弯承载力和延性的重要因素,随着翼缘宽厚比的增大,在试验梁屈服后的非弹性阶段,受压翼缘局部屈曲出现的较早,且受压翼缘的局部屈曲程度更显著,降低了钢梁非弹性阶段的变形能力。In order to study flexural behavior and ductility of high strength steel beam, the ben- ding test adopt three point loading was conducted on 3 hybrid high strength simple supported I beams fabricated by high performance steel HPS 485W （with nominal yield strength of 485 MPa） and traditional steel grade Q345. The strain, deformation characteristics, ultimate failure mode and flexural capacity were analyzed, during the whole loading process. The results show that the plastic joint is formed for each test beam at failure under effective lateral bracing. The failure mode of these 3 test beams is local buckling in both compressive flange and compressive web near the mid-span. For the hybrid high strength steel beam, there are an optimal steel grade combina- tion field between flange and web. When the higher strength HPS 485W flanges are adopted, the web strength is suggested to be more than that of Q345. Dimension of flanges is the maior factor affecting both flexural capacity and ductility of test beam. With the increase of flange slender- ness, the local buckling in compressive flange occurs much earlier and the amplitude of buckling wave is much greater at inelastic loading phase, thus the ductility in inelastic region is reduced. 4 tabs, 11 figs, 16 refs.

关 键 词：桥梁工程 高强度钢 混合设计 抗弯性能 承载能力 延性 

分 类 号：U441.2[建筑科学—桥梁与隧道工程]