【摘要】 基于13个高延性混凝土(HDC)短柱和2个混凝土(RC)短柱的低周期反复荷载试验，研究了轴压比、剪跨比和配箍率对HDC短柱抗剪承载力和变形能力的影响。HDC具有拉伸应变-硬化特性和多裂缝开展机制，HDC短柱的抗剪机制不同于RC短柱;发生剪切破坏时，HDC裂缝间纤维桥联作用可参与抗剪;发生剪切-黏结破坏时，HDC短柱纵筋的黏结劈裂破坏可得到有效抑制; HDC在受拉或受压时均比混凝土表现出更高的变形能力，HDC短柱塑性变形能力较RC短柱明显提高，发生剪切破坏和剪切-黏结破坏时，HDC短柱极限位移角较RC短柱分别至少提高57%和42%。基于桁架-拱理论，将HDC短柱裂缝间的纤维抗剪贡献计入桁架机构得到HDC短柱的抗剪承载力计算公式，其计算结果与试验结果吻合较好。更多还原

【Abstract】 Based on the low cyclic loading test of thirteen high ductile concrete( HDC) short columns and two reinforced concrete( RC) short columns,the effects of axial load ratio,shear span ratio and stirrup ratio on shear capacity and deformation capacity of HDC short columns were studied. The shear mechanism of HDC short columns is different from that of RC short column due to the tensile strain-hardening behavior and multiple crack mechanism of HDC. The fiber bridging effect of HDC after cracking contributes to the shear strength of the columns when they failed in shear. The bond-splitting failure of the longitudinal bars in HDC short columns can be effectively suppressed when they failed in shear bond.Compared with concrete,HDC exhibits much higher deformation capacity in tension or compression,thus the plastic deformation capacity of HDC short columns is much higher than that of RC short column. When HDC short columns fail in shear and shear-bond,the ultimate drift ratios of HDC short columns are at least 57% and 42% higher than that of RC short columns,respectively. Based on the truss-arch theory,the shear contribution of the fibers between the cracks in HDC short columns was added to the truss mechanism and a calculation formula of the shear capacity for HDC short columns was proposed. The calculated results are in good agreement with the experimental results.更多还原