充填率对新型窄幅钢箱-UHPC组合梁抗弯强度影响  

Effectof filling rateon bending strengthof UHPC-narrow steel boxcomposite beams

作　　者：郑艳 刘振华[2] 莫时旭 羊海林[2] ZHENG Yan;LIU Zhenhua;MO Shixu;YANG Hailin(Guangxi Key Laboratory of Green Building Materials and Construction Industrialization,Guilin 541004,China;College of Civil Engineering and Architecture,Guilin University of Technology,Guilin 541004,China)

机构地区：[1]广西绿色建材与建筑工业化重点实验室,广西桂林541004 [2]桂林理工大学土木与建筑工程学院,广西桂林541004

出　　处：《混凝土》2025年第2期32-38,共7页Concrete

基　　金：国家自然科学基金(52068012);广西自然科学基金(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)。

摘　　要：为研究充填率对窄幅钢箱-UHPC组合梁负弯矩下抗弯承载力的影响,设计3根UHPC-NC翼板窄幅钢箱组合梁进行静力加载试验。试验结果表明:钢箱内UHPC充填率对组合梁的开裂弯矩影响不大,钢箱内充填UHPC可以显著提高组合梁的屈服弯矩与极限抗弯承载力,与空钢箱组合梁相比,半充填和全充填UHPC组合梁其极限荷载分别提高了38%和56%。充填UHPC通过与钢箱共同受压以提高钢箱受压区局部稳定性,从而影响组合梁的抗弯承载力。基于截面应力法提出了UHPC-NC翼板窄幅钢箱组合梁开裂弯矩计算方法,并基于简化塑性理论提出了UHPC-NC翼板窄幅钢箱组合梁极限抗弯承载力的计算方法,试验值与计算值吻合良好。以充填率为参数,分析其对抗弯强度的影响,结果表明充填率为0.3~0.5时对UHPC-NC翼板窄幅钢箱组合梁较为合适。In order to study the effect of filling rate on the bending capacity of UHPC-narrow steel box composite beams under negative bending moment,three UHPC-NC flange narrow steel box composite beams were designed for static loading test.The test results show that the filling rate of UHPC in the steel box has little effect on the cracking moment of the composite beams,but the infilled UHPC in the steel box significantly improves the yield bending moment and ultimate bending capacity.Compared with the empty steel box composite beam,the ultimate load of the semi-filled and full-filled UHPC composite beam was increased by 38%and 56%,respectively.Infilled UHPC can bear pressure combined with steel box so as to improve the local stability of steel box in compression zone,thus affects the bending capacity of composite beams.The cracking moment calculation method of UHPC-NC flange narrow steel box composite beams was proposed based on the sectional stress method.And the ultimate bending capacity calculation method of UHPC-NC flange narrow steel box composite beams was proposed based on the simplified plastic theory.The experimental values were in good agreement with the calculated ones.The effect of filling rate on bending strength was analyzed,and the results show that the filling rate from 0.3 to 0.5 is suitable for UHPC-NC flange narrow steel box composite beams.

关 键 词：组合梁 UHPC-NC翼板 窄幅钢箱 充填率 抗弯承载力 

分 类 号：TU528.01[建筑科学—建筑技术科学]