高延性纤维混凝土短柱抗震性能试验研究

Experimental study on seismic behavior of high ductile fiber reinforced concrete short column

为研究高延性纤维混凝土短柱的抗震性能和变形能力,设计了5个剪跨比为2的高延性纤维混凝土短柱和1个作为对比试件的钢筋混凝土短柱,通过拟静力试验,研究其破坏形态、变形能力及耗能能力。试验结果表明:高延性纤维混凝土短柱破坏时,剪切斜裂缝开展缓慢,高延性纤维混凝土的受拉应变硬化和多裂缝开展性能可有效控制剪切斜裂缝的开展,显著改善短柱的脆性剪切破坏模式;与钢筋混凝土短柱相比,高延性纤维混凝土短柱的刚度退化缓慢,承载力、延性和耗能能力均明显提高;高延性纤维混凝土短柱的开裂、屈服和极限位移明显高于钢筋混凝土短柱,表明采用高延性纤维混凝土可显著提高短柱的剪切变形能力,提高其抗震性能和耐损伤能力。

In order to improve the seismic behavior and deformability of the short columns,five high ductile fiber reinforced concrete（ HDC） short columns with shear span ratios λ = 2 were designed,and one reinforced concrete（ RC） short column was designed for comparison. The failure pattern,energy dissipation capacity and deformation capacity of the short columns were studied by the quasi-static tests. The research shows that the inclined crack of the HDC short columns develops slowly when it is damaged,which suggests that the tensile strain hardening and multiple cracking performance of HDC can effectively control the development of shear inclined crack. Compared with RC short column,the stiffness degradation of the HDC short columns is slow,and the shear capacity,deformability and energy dissipation capacity of them are obviously improved. The displacements at cracking,yielding and failure of HDC short column are obviously higher than those of RC short column,suggesting that the HDC short column can obviously improve the shear properties. Using HDC can significantly improve the brittle shear damage mode of the short column,and enhance the seismic behavior and damage tolerance of key component.