传统风格建筑钢结构檐柱刚度分析

STIFFNESS ANALYSIS OF STEEL EAVE COLUMNS IN TRADITIONAL STYLE BUILDING

通过对4个传统风格建筑钢结构檐柱在低周往复加载下的试验研究,分析了各檐柱连接区域应变变化情况及其破坏形态,进而研究了各试件在加载全过程的刚度变化规律。分析结果表明:各试件的破坏均为方钢管柱根部屈曲、焊缝开裂及母材拉裂;各试件刚度退化曲线基本对称;轴压比相同时,长细比大的试件其刚度退化速率大;长细比相同时,各试件刚度退化曲线基本平行,其衰减速率基本相等;各试件刚度衰减均表现出由快到慢的规律;得到了层间位移角与刚度退化之间的关系曲线;试件达到极限荷载时,其层间位移角远大于GB 50011—2010《建筑抗震设计规范》规定的限值,表现了良好的变形能力。

Based on the experiment of four steel eave columns in traditional style building under quasi-static loading,the strain of eave column connections and failure modes were analyzed,and then the degradation of stiffness during the loading was studied. The results showed that the failure of specimens were caused by buckling,weld cracking and tension fracture of the base metal at the root of square column. Curves of stiffness degradation were generally symmetric. The rate of stiffness degradation appeared to increase with the increment of slenderness ratio. However,the rate of stiffness degradation turned to be larger as axial compression ratio increased. The curves of stiffness degradation were basically paralleled,and the decay rate was almost equal. In addition,the laws of stiffness degradation showed fast at the beginning and slow finally. At the same time the curves between inter-story drift ratio and stiffness degradation of specimens were obtained. The inter-story drift ratio of specimens was much larger than that of the limited value in GB 50011—2010 under the ultimate loading,which indicated that the eave columns had better deformability.