中文摘要：

利用专门的试验装置进行了24个钢筋混凝土框架梁试验，对梁中拱效应进行了系统研究，得到了不同加载速度下梁中轴力、支座约束弯矩和荷载与挠度关系曲线．试验证明拱效应可显著提高框架梁的极限承载力，试验值与按塑性铰理论计算值比值的平均值为1．94．影响框架梁中拱效应的主要因素是纵向钢筋配筋率、跨高比和支座约束刚度，其中配筋率的影响最显著．快速加载情况下框架梁中拱效应与静载条件下相同，随加载速率提高承载力增加．

英文摘要：

To determine the effects of arching action in reinforced concrete frame-beams, 24 specimens were tested using the special equipment. Curves were obtained on the axial compress force in beams, beam end restrained moment and load with the midspan deflection under different loading velocities. It was proved that arching action can significantly enhance the load-carrying capacity of reinforced concrete frame-beams. The mean of the rate of experimental ultimate loads to the calculational ultimate loads based on the plast yield theory was 1.94. The main factors that affect the arching action were the percentage of steel reinforcement, the rate of clear span to overdepth and support stiffness. In these factors the effect of percentage of steel reinforcement was bigger. The behaviors of beams under fast loading and static loading were similar. And the ultimate load increased with increase in loading velocity.