连续冲击下钢筋混凝土板的动态响应分析

Analysis of the dynamic response of reinforced concrete slabs under continuous impact

为了研究连续增幅冲击下钢筋混凝土板的动态效应,采用LS-DYNA显示动力算法对板件进行了3次连续冲击荷载下的数值模拟试验,分析了3次冲击的破坏模式,并提取了其能量时程曲线和冲击力时程曲线。结果表明,在连续冲击荷载作用下,混凝土的损伤面积逐次增大,条状裂缝宽度也随之扩大,冲击响应变得更加复杂;随着冲击能量输入的增加,混凝土板将不再能独自完成能量的转换,钢筋在冲击过程中会起到良好的能量耗散的作用;落锤冲击力峰值随着落锤高度的增加而变大,冲击力首个波段时长随着板件损伤程度的加深而变长。

In order to study the dynamic effects of reinforced concrete slabs under continuous increasing impact,the LS-DYNA display dynamics algorithm was used to numerically simulate the slabs under three continuous impact loads,analyze the damage modes of the three impacts,and extract their energy time course curves and impact force time course curves.The results show that under continuous impact loading,the damage area of concrete increases gradually,the width of strip cracks also expands,and the impact response becomes more complicated;with the increase of impact energy input,the concrete slab will no longer be able to complete the energy conversion alone,and the steel reinforcement will play a good role in energy dissipation during the impact pro-cess;the peak of the falling hammer impact force becomes larger with the increase of the height of the falling hammer,and the first wave duration of impact force becomes longer as the degree of damage to the slab deepens.