PC梁开裂截面应力计算的简化方法探讨

Discussion of Simplifying Method of PC Beam Cracking Section Stress Calculation

根据预应力混凝土梁再开裂正截面预应力钢筋的应力计算经验公式,推导梁正截面首次开裂后再开裂过程中中性轴位置和受压区边缘混凝土正应力的计算新方法,其间考虑了预应力混凝土梁正截面首次开裂以及疲劳荷载重复作用对钢筋和混凝土应力增长的影响,并通过算例对新方法与现有方法的计算结果进行比较,验证了新方法的简便合理性。

Based on the stress calculation formula of the re-cracking positive section pre-stressed steel bar of the pre-stressed concrete beam, the article introduces the new calculation method of the concrete direct stress at the neutral axis position and at the edge of the compressed area in the course of the positive section re-cracking of beam after the first time of cracking, in which the article considers the influence of the first cracking of positive section of pre-stressed concrete beam and the repeating action of fatigue load on the steel bar and the concrete stress increment, and the article compares the calculation results of the new method and the existing method by the calculation formulas to validate the simple and convenient reasonableness of the new method.