摘要
为研究UHPC-部分充填窄幅钢箱组合梁负弯矩下的抗弯性能,制作了6根试验梁探究翼板配筋率、UHPC钢纤维掺量及板厚对组合梁截面应变分布、破坏形式及极限承载力的影响。试验结果表明:3%钢纤维掺量的UHPC翼板开裂荷载比0、1%、2%钢纤维掺量的UHPC翼板分别大63.1%、29.8%、7.7%,说明钢纤维的加入,能够控制裂缝的发展,提高翼板的塑性,可有效改善破坏时的脆性现象。翼板配筋率提高1%时,抗弯承载力提高5.3%。用UHPC替代翼板1/2厚度的普通混凝土,开裂能力提高了56.2%,极限荷载提高了7%。基于简化塑性理论提出了组合梁抗弯承载力计算式,计算值与试验值吻合较好。
In order to study the flexural performance of UHPC-partially flled composite beam with narrow steel box girder under hogging moment,six test specimens were fabricated to explore the influence of reinforcement ratio,UHPC steel fiber content and flange thickness on sectional strain distribution,failure mode and ultimate bearing capacity of composite beams.The experimental results showed that the cracking load of UHPC flange with 3%steel fiber content was 63.1%,29.8%,7.7%higher than that with 0,1%,2%steel fiber content,respectively.It shows that the addition of steel fiber can control the development of cracks,improve the plasticity of flange,and effectively improve the brittleness phenomenon.The bending capacity was increased by 5.3%with reinforcement ratio of flange increased by 1%.When UHPC was used to replace the ordinary concrete with 1/2 thickness of flange,the cracking ability was increased by 56.2%and the ultimate load increased by 7%.A formula for calculating the flexural capacity of composite beams was proposed based on the simplified plasticity theory.The calculated values are in good agreement with the experimental ones.
作者
郑艳
刘帅
羊海林
柴龙杰
农双秀
黄荆
ZHENG Yan;LIU Shuai;YANG Hailin;CHAI Longjie;NONG Shuangxiu;HUANG Jing(Guangxi Key Laboratory of Rock-Soil Mechanic and Engineering,Guilin 541004,China;College of Civil Engineering and Architecture,Guilin University of Technology,Guilin 541004,China)
出处
《混凝土》
CAS
北大核心
2024年第7期28-32,38,共6页
Concrete
基金
国家自然科学基金(52068012)
广西自然科学基金(2021GXNSFAA220101)。
关键词
钢箱组合梁
UHPC
抗弯性能
负弯矩
承载能力
stel box girder composite beam
UHPC
flexural performance
hogging moment
bearing capacity
