摘要
为研究钢箱-超高性能混凝土(UHPC)组合梁负弯矩区裂缝特征,设计制作了3根配筋率分别为1%、2%和3%的UHPC翼板部分充填砼窄幅钢箱组合梁,通过对不同配筋率的试验梁进行反向加载试验研究组合梁的裂缝发展特征,并对最大裂缝宽度、裂缝间距及开裂荷载进行对比分析。研究结果表明:试验梁在不同配筋率条件下,UHPC面层裂缝发展明显不同,配筋率越高最大裂缝宽度越小,裂缝越密集,开裂荷载越大;与配筋率为1%的试验梁相比,配筋率为2%和3%的试验梁的开裂弯矩分别提高了30.3%和65.2%;可根据《公路钢筋混凝土及预应力混凝土桥涵设计规范》(JTG 3362—2018)中的裂缝宽度计算公式乘以0.78的修正系数,来计算窄幅钢箱-UHPC组合梁负弯矩区的裂缝宽度。
In order to study the crack characteristics of steel box-ultra-high performance concrete(UHPC)composite beam in negative bending moment zone,three partially-filled narrow steel box-UHPC flange composite beams with reinforcement ratios of 1%,2%and 3%were designed and manufactured.The crack development characteristics of the composite beams with different reinforcement ratios were observed by reverse loading test,and the maximum crack width,crack spacing and crack load were compared and analyzed.The research results show that the crack development of UHPC surface layer is obviously different with different reinforcement ratios.The higher the reinforcement ratio is,the smaller the maximum crack width,the denser the crack spacing and the greater the crack load become.Compared with the specimens with reinforcement ratio of 1%,the cracking bending moment of the specimens with reinforcement ratio of 2%and 3%increased by 30.3%and 65.2%respectively.The crack width of narrow steel box-UHPC composite beams in negative moment zone can be calculated with the crack width calculation formula in the Specifications for Design of Highway Reinforced Concrete and Prestressed Concrete Bridges and Culverts(JTG 3362—2018)by multiplying a correction factor of 0.78.
作者
莫时旭
房洋洋
郑艳
农双秀
MO Shixu;FANG Yangyang;ZHENG Yan;NONG Shuangxiu(College of Civil Engineering and Architecture,Guilin University of Technology,Guilin 541004,China;Guangxi Key Laboratory of Green Building Materials and Construction Industrialization,Guilin 541004,China)
出处
《山东科技大学学报（自然科学版）》
CAS
北大核心
2024年第3期85-93,共9页
Journal of Shandong University of Science and Technology(Natural Science)
基金
国家自然科学基金项目(52068012)
广西自然科学基金项目(2021GXNSFAA220101)
广西绿色建材与建筑工业化重点实验室项目(桂科能22-J-21-1)。
关键词
窄幅钢箱组合梁
配筋率
裂缝发展特征
负弯矩区
narrow steel box composite beam
reinforcement ratio
crack development characteristics
negative bending moment zone
