部分充填式钢箱-混凝土组合梁的负弯矩区裂缝宽度

Crack Width of Concrete-Partially-Filled Steel Box Composite Beam Under Negative Moment

对4根反向加载的部分充填式钢箱-混凝土组合梁进行单调受弯试验,并对影响组合梁负弯矩区裂缝的因素进行分析.根据试验与理论分析,完善考虑混凝土收缩应力的部分充填式钢箱-混凝土组合梁负弯矩区开裂弯矩计算方法.对负弯矩区不同力比的组合梁裂缝宽度试验观测值与各文献计算值进行对比.结果表明:力比是影响组合梁裂缝发展的主要因素,栓钉的布置和钢梁内充填的混凝土对裂缝的发展也有影响.

A flexural test was carried out on four concrete-partially-filled steel box composite beams with reverse loading.The factors that influence the cracks in the negative moment region of the composite beams was analyzed.According to the experimental and theoretical analysis,the method to calculate the cracking moment of the concrete-partially-filled steel box composite beam in the negative moment region considering the concrete shrinkage stress was modified.The test results of crack width in the negative moment region of the composite beams with different force ratios were compared with the calculation values in other references.It is indicated that force ratio is the main factor affecting the development of the crack width of composite beams,while the layout of stud and the concrete filled in the steel beams also influence the crack width.