用改良模型分析缺陷混凝土梁的动强度

Numerical Analysis on the Modified Model to the Dynamic Strength of Defective Concrete Beam

改进了传统的数字混凝土建模方法,利用新方法建立了存在初始缺陷的混凝土梁三点弯数值试验模型,随后对所建立的模型进行了3种工况的数值模拟。分析了初始缺陷的存在对混凝土动强度的影响规律,结果显示:在加载初期,加载速率越高,初始缺陷对材料动强度的影响越明显,但是在加载后期此影响减弱;当荷载达到材料的强度点时,不同的加载速率下,初始缺陷对混凝土材料动强度影响均不显著。通过与试验结果的对比,发现改进后的模型计算精度高于传统模型,计算结果更加合理,在工程实际当中能够取代传统的数字混凝土模型。

By improving the traditional digital concrete modeling method,the new defective concrete model was established.Three cases were simulated based on this model.The influence of initial defectiveness on the dynamic strength was investigated.The result shows that： 1） At initial stage,the influence of the initial defectiveness on the dynamic strength becomes more obviously with the increasing of the loading speed;2） Regardless of the same loading speed,the influence becomes less obviously when the load reaches the strength point of the concrete;3）The simulation result is compared with the test result,and it is deduced that the new model has higher computational accuracy and the result is more rational,and it can take the place of the traditional digital concrete model in practice.