冲击荷载下钢筋混凝土梁局部响应特征研究

从分析已有冲击试验结果入手,将钢筋混凝土梁的动态响应区分为局部响应阶段和整体响应阶段.由于钢筋混凝土梁在局部响应阶段更易发生脆性剪切破坏,本文主要研究此阶段梁的瞬态响应.讨论了惯性力和负向支座反力对梁内力分布的影响;根据荷载平衡基本原理和参数分析结果建立了梁内力分布的计算方法.结果表明:惯性力和负向支座反力均会影响梁体局部响应阶段的内力分布;负向支座反力近似与梁的跨高比和碰撞力呈线性关系;将惯性力的分布简化为线性分布能够较好地反映梁的实际受力状态.

Study on Local Response Characteristics of RC Beams under Impact Loading

Based on the existing experimental results, the dynamic response of RC beams under impact loading is divided into local response stage and overall response stage. As RC beams are vulnerable to shear failure during the local response stage, this study investigates the transient response of the components in this stage. Thus, the effect of inertial force and reverse reaction on the internal force distribution at the local response stage is also discussed. Based on the basic principles of force equilibrium and parametric analysis results, a computing method for the internal force of RC beams is proposed. The results show that both the inertial force and negative reverse reaction affect the internal force distribution of beams during the local response stage, and the reverse reaction is approximately linear to the span-depth ratio and peak impact force. The assumption that the distribution of inertial force is linear can well reflect the actual force state of the beam.