空心率对空心钢管混凝土轴压短柱工作性能及承载力影响的研究

进行了55根各种截面的空心钢管混凝土轴心受压短柱试验,研究了不同截面参数情况下,空心钢管混凝土轴压短柱承载力性能变化,研究了空心率对平均应力与纵向应变性能的影响。研究结果表明:圆形截面试件的承载力高于其他类型截面的试件,试件空心率越小,试件的承载力越高,轴压曲线的弹塑性阶段越长,同时曲线的下降段越趋平缓,随着空心率的变化,短柱的轴压曲线呈系列化,上述结果体现了空心钢管混凝土结构的连续性。同时根据试验结果验证了空心钢管混凝土轴压短柱组合强度标准值的计算公式,计算值与试验值相比吻合良好,说明使用该公式计算空心钢管混凝土轴心受压短柱的承载力是可行的。

STUDY ON INFLUENCE OF HOLLOW RATIO TO BEARING CAPACITY OF H-CFST

The influence of sectional parameters to ultimate bearing capacity of hollow-concrete-filled steel tube (H-CFST) under axial loading is investigated through 55 test specimens,and the influence of hollow ratio to stress-strain relations is analyzed. The experimental results show that ultimate bearing capacity of circular section specimens is higher than that of other section specimens, the results also show that the higher the hollow ratio is, the more flat the descending segments of stress-strain curves is, and the shorter the elastic-plastic stage is, the lower the ultimate bearing capacity is. This implies that the continuity of H-CFST is sound with the change of sectional parameters. Contrasting with the experimental results, formula used to calculate composite standard compressive strength is proved to be correct.