In this paper, the induced stress in longitudinal reinforcement bars with cross sections subjected to concrete creep and shrinkage was evaluated. The study was performed for a reinforced concrete column, with loading varying from zero—in which the structure is exclusively subjected to self-weight—to forces close to the loss of stability by bifurcation of equilibrium. A real precast concrete pole, extremely slender, with geometry varying lengthwise, was the structure chosen for the analysis. The aspects related to the material nonlinearity, as well as creep, shrinkage and the development of characteristic concrete strength, were taken into account following Brazilian normative recommendations in NBR 6118:2014 (Design of structural concrete—Procedure) by the Brazilian Association of Technical Standards (ABNT). The critical buckling load was defined according to the structural frequency by using particularly nonlinear formulations. The results were obtained for different instants without exceeding the expected time for convergence of results. The maximum relative value found for the reinforcement stress was 1.24% of the steel yield strength, eliminating the possibility of yielding material.

在本文中，评估了纵向钢筋在横截面上受到混凝土蠕变和收缩的诱导应力。这项研究是针对钢筋混凝土柱进行的，载荷从零（其中的结构仅承受自重）到接近因平衡分叉而失去稳定性的力。选择用于分析的结构是一根真正纤细的预制混凝土杆，几何形状沿长度方向变化。遵循巴西技术标准协会NBR 6118：2014（结构混凝土的设计－程序）中的巴西规范性建议，考虑了与材料非线性以及蠕变，收缩和混凝土特性强度的发展有关的方面。 （ABNT）。通过使用特别是非线性公式，根据结构频率定义了临界屈曲载荷。在不超过预期结果收敛时间的情况下，获得了不同时刻的结果。增强应力的最大相对值为钢屈服强度的1.24％，从而消除了材料屈服的可能性。