矩形钢管混凝土柱热屈曲分析

Thermal buckling analysis of rectangular concrete-filled steel tube

为对矩形钢管混凝土柱热屈曲的影响因素进行分析,假定矩形钢管混凝土柱非加载边和加载边都固定,柱子不受外力只受高温作用,选择满足四边固定边界条件的屈曲位移函数后利用能量法求得热屈曲系数,进一步得到热屈曲变温的表达式,最后分析了长宽比、宽厚比等参数对热屈曲变温的影响.结果表明：纵向热屈曲荷载和常温屈曲荷载存在线性关系;当长宽比在1~2.5时,长宽比对屈曲变温T的影响较大;随着宽厚比增大,屈曲变温减小.

To analyze the influence factors of thermal buckling of rectangular concrete-filled steel tube column, assuming that the load and the load boundary of the rectangular concrete-filled steel tube column are all fixed, and the column only subjects to high temperature and not be affected by external forces, this paper chose the buckling displacement function which meets the condition of fixed four edge boundary and calculated the thermal buckling coefficient by energy method, and further obtained the expression of the thermal buckling, finally analyzed the influences of aspect ratio and width-thickness ratio etc. parameters on the thermal buckling temperature. The results show that the longitudinal thermal buckling load and buckling load under normal temperature exist linear relationship; When the aspect ratio is within 1 - 2.5, the influence of aspect ratio on the buckling temperature T is larger; With the increase of the width-thickness ratio, buckling temperature decreases.