型钢高延性混凝土短柱抗震性能试验研究

EXPERIMENTAL STUDY ON SEISMIC BEHAVIOR OF STEEL REINFORCED HIGH DUCTILE CONCRETE SHORT COLUMNS

提出采用高延性混凝土和核心区配置型钢提高短柱的抗震性能和变形能力,设计了2个高延性纤维混凝土(HDC)短柱和2个型钢高延性混凝土(SHDC)短柱试件,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:试件剪跨比减小,有利于发挥HDC良好的抗剪性能,使HDC短柱表现出良好的延性和耗能能力;核心区配置型钢,可显著提高HDC短柱的延性和耗能能力,提高构件的耐损伤能力;HDC与型钢具有良好的协调变形能力,改善了短柱的脆性剪切破坏模式,使SHDC短柱发生剪切粘结破坏时仍表现出较好的延性;SHDC短柱在不同性能水平下的变形能力明显高于HDC短柱,能满足我国规范对框架结构竖向构件的变形要求。

2 high ductile fiber reinforced concrete（HDC） columns and 2 steel reinforced high ductile concrete（SHDC） short columns, using high ductile fiber reinforced concrete and allocating steel in core area to improve the seismic behavior and deformability of short columns, were put through pseudo-static testing to determine their failure modes, deformability and energy dissipation ability. The research shows that a decrease in shear-span ratio is beneficial to the good shear performance of HDC, which results in good ductility and energy dissipation capacity in HDC short columns. Allocating steel in the core area can significantly improve the ductility and energy dissipation capacity of HDC short columns, thus improving the damage resistance of members. Good adherence, allowing compatible deformation between steel and HDC, can improve the brittle shear failure mode of short columns, allowing SHDC short columns to maintain good ductility even after shear-bond failure occurs. Additionally, the deformation capacity of SHDC short columns at different performance levels is obviously higher than that of HDC short columns, and they are able to meet the deformation requirements for vertical members in the Chinese Code.