The main purpose of this work is to understand the structural characterization of reinforced concrete slabs under near-field and contact explosions using the developed rate-sensitive damage model. The model is developed based on the experimental observation to include the effects of strain rate and damage rate. It is observed that with increasing strain rates there is a decrease in damage evolution due to artificial stiffening effects and the final level of damage is higher. This is achieved by using a power law model to relate the rate of damage to the equivalent plastic strain rate. The concrete undergoes pulverized damage because of the loss in cohesive strength at higher hydrostatic stress. Thus, the hydrostatic damage has to be considered along with tension and compression damage parameter. Strong volumetric deformation of the material that includes the hydrostatic and compaction damage is also accounted for in the model. The size of the yield surface increases with strain rate and is capped with an upper limiting value. The incremental effective stress–strain relationships are defined in terms of rate of damage, accumulated damage and viscosity parameters reflecting the inherent physical inertial, thermal and viscous mechanisms respectively. The results from the numerical analysis are found to match well with experimentally observed results.

这项工作的主要目的是使用开发的速率敏感损伤模型来了解近场和接触爆炸下钢筋混凝土板的结构特征。该模型是根据实验观察开发的，包括应变率和损伤率的影响。据观察，随着应变率的增加，由于人工硬化效应，损伤演变会减少，最终损伤水平会更高。这是通过使用幂律模型将损坏率与等效塑性应变率联系起来来实现的。由于较高静水应力下内聚强度的损失，混凝土会遭受粉化损坏。因此，必须考虑流体静力学损伤以及拉伸和压缩损伤参数。模型中还考虑了材料的强烈体积变形，包括静水压损伤和压实损伤。屈服面的尺寸随着应变速率的增加而增加，并有一个上限值。增量有效应力-应变关系是根据损伤率、累积损伤和粘度参数来定义的，分别反映了固有的物理惯性、热力和粘性机制。发现数值分析的结果与实验观察到的结果非常吻合。累积损伤和粘度参数分别反映了固有的物理惯性、热力和粘性机制。发现数值分析的结果与实验观察到的结果非常吻合。累积损伤和粘度参数分别反映了固有的物理惯性、热力和粘性机制。发现数值分析的结果与实验观察到的结果非常吻合。