考虑二阶效应的火灾后等肢L形型钢混凝土异形柱偏心距增大系数的研究  

RESEARCH ON THE ECCENTRICITY MAGNIFIED COEFFICIENT OF L-SHAPED SRC COLUMNS WITH EQUAL LEGS AFTER FIRE CONSIDERING SECOND-ORDER EFFECT

作　　者：高立堂[1] 李凌敏[1] 杨超[1] 蔡维沛 

机构地区：[1]青岛理工大学土木工程学院,山东青岛266033

出　　处：《钢结构》2016年第9期107-110,共4页Steel Construction

基　　金：国家自然科学基金项目(51178232/E080804)

摘　　要：为了研究考虑二阶效应的火灾后等肢L形型钢混凝土异形柱的偏心距增大系数,在8根受火1 h后的等肢L形型钢混凝土异形柱常温静力加载试验的基础上,测其侧向变形曲线,计算出偏心距增大系数η1,然后将L形截面按照等形心轴惯性矩的原则等效成矩形截面并与异形柱的η2进行比较。为火灾后异形柱偏心距增大系数的计算提供参考和依据。研究表明:通过比较,除DL5的偏心距增大系数相差较大以外,其余计算出的偏心距增大系数比较接近,相差均在10%以内;DL5—DL8异形截面柱的偏心距增大系数要小于矩形截面柱的偏心距增大系数,最大值为10.47%出现在DL5的Y肢方向,表明对于受火后的异形柱来说,双向偏心受压的加载方式更为不利。8 L-shaped steel reinforced concrete columns with equal legs were used to conduct static loading test after 1hour of fire,so as to analyze the eccentricity magnified coeddicient considering second-order effect. According to the lateral deformation curve,the eccentricity magnified coefficient η1was obtained and compared with η2,and could provide a reference to the calculation of the eccentricity magnified coefficient of special-shaped column after fire. Because of the higher amount of steel,the L-shaped cross-section was converted into a rectangular cross-section based on the principle of equal-centroidal axis inertia moment. The results showed that： through the comparative analysis,the calculated eccentricity magnified coefficient relatively close except column DL5,the difference was less than 10%; the eccentricity magnified coefficient of shaped columns was smaller than that of rectangular columns with a maximum of 10. 47% for column DL5—DL8 which appeared in the Y direction of column DL5,a two-way eccentric compression loading was more unfavorable for the column after fire.

关 键 词：等肢L形型钢混凝土异形柱 二阶效应 偏心距增大系数 火灾后 

分 类 号：TU398.9[建筑科学—结构工程]