中文摘要：

为研究部分充填式钢箱-混凝土组合梁在负弯矩作用下混凝土的开裂特征,进行了2根反向加载的简支梁的静载试验。试验结果表明：组合梁混凝土板中的裂缝分布特征与配筋率有关,混凝土在荷载较低时就发生开裂,且裂缝间距与横向钢筋间距有一定的关系;当配筋率较小时混凝土开裂导致其邻近的钢筋应变立刻增加且裂缝分布相对稀疏;随着荷载的逐渐增加,纵向钢筋开始屈服,裂缝迅速发展,裂缝宽度逐渐加宽,增长较快;此外,剪力钉间距、部分填充混凝土的密实度、栓钉数量及布置方式也是影响部分充填式钢箱-混凝土板裂缝宽度的重要因素。

英文摘要：

For the study of concrete cracking characteristics in the negative moment region of concrete-partially-filled steel box composite beam,static load tests were conducted on two simply supported steel-concrete composite beams under point loads.The results show that the crack distribution of concrete slab composite beam is related to the reinforcement ratio,the concrete slab cracks when the load level is low and the space among cracks have something to do with the transverse reinforcement space; that,for the composite girder with less reinforcement ratio,the strain of reinforcement increases immediately after concrete cracks,and the crack distribution is relatively sparse; that,with the increase of load level,the longitudinal reinforcement begins to yield,cracks develop rapidly,and crack width is gradually widened and grows rapidly.In addition,the spacing of shear stud,the compactness of concrete-partially-filled concrete,and the number of stud shear connectors as well as their arrangement is some important factors to the cracking width of concrete-partially-filled steel box composite slabs.