摘要
提出一种新型薄壁型钢UHPC组合箱梁,开展了6根薄壁型钢UHPC组合箱梁与1根薄壁型钢箱梁对比梁的四点弯曲静载试验,利用三维数字图像相关测量技术对箱梁的应力-应变与变形及裂缝性能进行测试分析。研究结果表明:外包UHPC能使薄壁型钢箱梁的破坏形态由局部压屈破坏转变为底部薄壁型钢下翼缘及纵筋先后达到屈服后顶部UHPC压碎的正截面受弯破坏;外包50 mm厚UHPC的未配纵筋与箍筋的组合箱梁试件XL2的正截面受弯承载力比薄壁型钢箱梁试件XL1的对应值提升77.5%;薄壁型钢表面焊接了纵筋与箍筋的组合箱梁试件XL3~XL7的整体协同工作性能得到了大幅度提升,其中,XL4试件的正截面受弯承载力比未配纵筋与箍筋的XL2试件的对应值提升了178.8%;增大薄壁型钢壁厚与外包UHPC层厚度也能在一定程度上提高薄壁型钢UHPC组合箱梁的正截面受弯承载力与抗裂能力。
A new thin-walled steel UHPC composite box beam was proposed.The four-point bending static load test of six thin-walled steel UHPC composite box beams and one thin-walled steel box beam for comparison were carried out,and the 3D digital image correlation measurement technology was used to test and analyze the stress-strain,deformation and cracking development properties of box beams.The results show that outsourcing UHPC can make the failure mode of thin-walled steel box beam change from"local buckling failure"to"bending failure at the positive section which is the bottom thin-walled steel lower flange and longitudinal bars yielded successively,and then the top UHPC crushes".The flexural capacity of the positive section of combined box beam specimen XL2 without longitudinal reinforcement and stirrups is 77.5%higher than that of the thin-walled steel box beam specimen XL1.The overall coordinated working performance of the combined box beam specimen XL3-XL7 with longitudinal bars and stirrups welded on the surface of thin-walled steel is greatly improved,and the flexural capacity of the positive section of the XL4 specimen is 178.8%higher than that of the XL2 specimen without longitudinal bars and stirrups.At the same time,increasing the thickness of thin-walled steel and UHPC can improve the flexural capacity of the positive section and crack resistance of thin-walled steel UHPC composite box beam to a certain extent.
作者
刘晓春
邹彩丽
胡文飞
郭风琪
朱志辉
余志武
LIU Xiaochun;ZOU Caili;HU Wenfei;GUO Fengqi;ZHU Zhihui;YU Zhiwu(National Engineering Research Center of High-speed Railway Construction Technology,Central South University,Changsha 410075,China;School of Civil Engineering,Central South University,Changsha 410075,China;China Three Gorges Construction Engineering Corporation,Ganzhou 341001,China)
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2024年第10期3887-3897,共11页
Journal of Central South University:Science and Technology
基金
国家自然科学基金资助项目(U1934217,52078498)
湖南省自然科学基金资助项目(2019JJ40383)
湖南省教育厅科研项目(18K003)。
关键词
钢UHPC组合箱梁
受弯性能
四点弯曲静载试验
数字图像相关
steel UHPC composite box beam
flexural behavior
four point bending static load test
digital image correlation
