港工钢筋混凝土梁的抗剪强度

• 作 者: 彭天明
• 机 构: 华东水利学院
• 出 处: 水运工程
• 发表日期: 1981年07期
• 关键词: 钢筋混凝土梁 抗剪强度 斜裂缝 箍筋 应力法 主拉应力 水运工程 规范公式 标准荷载 剪应力

一、概述 水运工程64年规范中有关钢筋混凝土梁的抗剪强度计算,规定采用许可应力法。它的理论与试验结果的比较以及材料用量的经济效果等方面都存在问题。例如,推导主拉应力公式时,正截面已发生裂缝的混凝土部分不能承担正应力,但却认为有剪应力存在;斜裂缝方向不论何种情况总是与梁轴成45°角;在使用荷载下箍筋和弯筋的实际应力远小于许可应力值;安全度不明确等。

First, an overview of 64-year Code of Shipping Code on the shear strength of reinforced concrete beams, the provisions of the allowable stress method. Its theoretical and experimental results, as well as the economic effect of the amount of material and other aspects of the problem. For example, when deriving the principal tensile stress formula, the cracked concrete portion of the normal cross-section can not assume normal stress but is considered to have shear stress; the direction of the oblique crack is always at a 45 ° angle to the beam axis; The actual stress of the stirrups and bending bars is much less than the allowable stress value; the safety is not clear and so on.