沿截面高度均匀配筋的钢筋混凝土偏心受压构件的配筋计算

THE STRENGTH CALCULATLON OF ECCENTRICALLY COMPRESSED REINFORCED CONCRETE MEMBERS WITH REINFORCEMENT IN FOUR FACES

摘要: 新的混凝土结构设计规范(第二次送审稿)(以下简称新规范),给出了沿截面高度均匀配置纵向钢筋的矫形、T形、I字形截面钢筋混凝土偏心受压构件的正截面强度计算的近似公式,但是,如果构件属于小偏心受压构件,则在具体计算受拉区、受压区的钢筋面积时,首先需要求解相对中和轴高度ξ的三次方程,计算十分复杂。本文讨论了沿截面高度均匀配筋的偏心受压构件的各种计算情况,推导出了便于进行配筋计算的计算公式。对于小偏心受压构件,则应用“分区降阶逼近法”来求解ξ值。文中计算公式,可供工程设计人员实际应用。

Abstract: An approximate strength calculation method of eccentrically compressed reinforced concrete members with reinforcement in four faces is given in the design of reinforced concrete structure. But for members with small eccentricity, a cubic equation of the relative neutral axis depth ξ should be solved in the reinforcement calculation, which is rather complicated. All the calculation conditions are systematically discussed and a convenient strength calculation method is deduced in this paper. The relative neutral axis depth ξ of the members with small eccentricity is solved using the approximation method by reducing power in separated regions.