配筋率对钢箱-砼组合梁受力性能影响  

Effect of Reinforcement Ratio on Steel Box/Concrete Composite Beams

作　　者：刘瑜 郑艳[2] LIU Yu;ZHENG Yan(Beijing Century Chief International Architecture Design Co.,Ltd.,Beijing 100089,China;College of Civil and Architecture Engineering,Guilin University of Technology,Guilin 541004,China)

机构地区：[1]北京世纪千府国际工程设计有限公司,北京100089 [2]桂林理工大学土木与建筑工程学院,桂林541004

出　　处：《科学技术与工程》2022年第11期4474-4480,共7页Science Technology and Engineering

基　　金：国家自然科学基金(52068012);广西自然科学基金(2019JJA160040)。

摘　　要：为研究配筋率对部分充填式钢箱-混凝土组合梁负弯矩下承载能力的影响,开展了3根不同配筋率的试验梁在两点对称反向加载方式下的受力性能试验;试验梁总长4.4 m,总高度0.42 m,其中钢箱截面宽0.12 m、高0.3 m,由隔板分为上下两室,下室充填混凝土,翼板厚0.12 m、宽1.0 m,配筋率为1%、2%和3%,钢箱梁与翼板采用焊接栓钉连接;试验得到了试验梁荷载-挠度曲线、荷载-应变曲线、破坏形态等结果。基于弹性理论用换算截面法分析了试验梁开裂后截面刚度的变化,以及配筋率对承载能力的影响。试验和分析结果表明,翼板配筋率对试验梁开裂弯矩影响不大;配筋率小于2.25%时,因翼板钢筋屈服而达到弹性极限状态,屈服弯矩由钢筋屈服强度控制,大于2.25%时,因钢箱底板屈服而达到弹性极限状态,屈服弯矩由底板钢材屈服强度控制;引入翼板受拉程度系数计算开裂后截面刚度更为合理。In order to study the effect of reinforcement ratio on concrete-partial-filled steel box composite beams,two point symmetrical reverse loading experiments of three specimens with different reinforcement ratios were carried out to investigate their mechanical behaviors.The three specimens were 4.4 m in total length and 0.42 m in height.The steel box girders of them were 0.12 m in width and 0.3 m in height.The steel boxes were divided into upper and lower rooms by partitions,and the lower rooms were filled with concrete.The concrete flanges were 0.12 m in height and 1.0 m in width,with reinforcement ratio of 1%,2%and 3%.The steel box girders and concrete flanges were connected by welding bolts.The load-deflection curve,load-strain curve and failure patterns of the specimens were obtained by tests.Based on the elastic theory,the changes of section stiffness after cracking were analyzed with transformed section method.And the effect of reinforcement ratio on bearing capacity was analyzed.The results of test and analysis show that the reinforcement ratio of flange has little effect on the cracking moment of specimens.When the reinforcement ratio is less than 2.25%,the elastic limit is reached due to the yield of the steel bars in flanges,so the yield bending capacity of specimen is controlled by the yield strength of steel reinforcements.Whilst the reinforcement ratio is more than 2.25%,the elastic limit is reached due to the yield of steel box bottom,thus the yield bending capacity is controlled by the yield strength of box bottom steel.It is reasonable to introduce the tensile degree coefficient of flange to calculate the section stiffness after cracking.

关 键 词：钢-混凝土组合梁 配筋率 抗弯刚度 屈服弯矩 

分 类 号：TU398.9[建筑科学—结构工程]