Abstract: Based on the empirical formulae calculating the tendon stresses on re-cracked cross sections of prestressed concrete beams, the positions of neutral axes and the normal stresses of compressive concrete edge fibers on re-cracked cross sections of prestressed concrete beams are determined in a new way, the amplifying effects of the first-time cracking and the cycling fatigue loads on the steel bar stresses and concrete stresses considered. A exemplificative prestressed concrete cross section is c...

Key words: prestressed concrete beams, re-crack, neutral axes, steel bar stresses, concrete stresses

摘要： 根据预应力砼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砼正应力的计算新方法，其间考虑了预应力砼梁正截面首次开裂以及疲劳荷载重复作用对 钢筋和砼应力增长的影响，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

关键词: 预应力砼梁, 再开裂, 中性轴, 钢筋应力, 砼应力