脉冲荷载作用下钢筋砼梁破坏形态分析

The Analysis of Failure Modes of RC Beams Under Impulsive Loading

在冲击、爆炸等脉冲荷载作用下 ,地下防护结构的破坏形态比核武器作用下的要复杂得多 ,可能由原来的延性弯坏变为脆性剪坏。以常规武器作用下土中浅埋钢筋混凝土框架结构为背景 ,将其顶板简化为梁或单向板 ,并基于 Timoshenko梁理论 ,采用有限差分方法 ,分析了钢筋混凝土梁或单向板的早期动力响应 ,最后提出了一种爆炸脉冲荷载作用下钢筋混凝土梁或单向板破坏形态的弹性预报方法。计算分析结果表明 ,预报方法与试验观察结果基本一致 ,具有一定的工程实用价值。

Under the impulsive loading such as impact and blasting ones, the failure modes of underground defense structures are much more complex than those under nuclear loading, as conventional ductile bending failure can be transformed into brittle shear failure. In this paper, the early stage dynamic response of roof slabs of shallow buried RC frame structures under conventional dynamic loads is studied. And a numerical prediction method for failure modes of this type of structures under impulsive loading is presented by using of the finite differential method based on the Timoshenko beam theory.The result demonstrates that a good agreement is obtained between the numerical prediction method for the failure modes and experimental observation,and that this prediction method has high engineering application values.