矩形截面偏心受压构件对称配筋设计判别大小偏心时分歧的探讨研究

The Investigation on the Differences of Small and Large Eccentrics Judgment for the Symmetrical Reinforcement Design of Rectangular Sectional Eccentric Compression Member

针对当前矩形截面偏心受压构件对称配筋设计时,对于如何判断大小偏心两种方法中出现的分歧,运用具体算例、判别条件的数值解法和判别条件的图解法进行了较为详细的分析研究。结果表明,按照ei和0.3h0间的关系来判别大小偏心时,必须附加截面相对受压区高度ξ和界限受压区高度ξb间的关系,否则就可能会出现误判,且这种误判主要集中于荷载较小时的情况;而按照直接用截面相对受压区高度ξ和界限受压区高度ξb间的关系判别大小偏心时,却不会出现误判。因此实际矩形截面偏心受压构件对称配筋设计时,可直接用截面相对受压区高度ξ和界限受压区高度ξb间的关系判别大小偏心。

Regarding how to judge the differences arising from two methods of small and large eccentrics for the symmetrical reinforcement design of rectangular sectional eccentric compression members, this paper conducted detailed research using concrete calculating example, numerical method and graphical method for determining conditions. The results showed that when small and large eccentrics are judged according to the relation between eiand 0.3 h0, the relation between sectional relative depth of the compression zone ξ and balanced depth of compression zone ξbmust be attached, otherwise misjudgment that mainly concentrates on low load would occur. Moreover, there is no misjudgment when directly judge the small and large eccentrics by the relation between sectional relative depth of the compression zone ξ and balanced depth of compression zone ξb.Hence, the relation between sectional relative depth of the compression zone ξ and balanced depth of compression zone ξbcan be directly used to judge the small and large eccentrics for the actual symmetrical reinforcement design of rectangular sectional eccentric compression members.