基于盖帽模型的混凝土动态球型空腔膨胀模型和侵彻阻力分析

Spherical Cavity-expansion Model for Concrete Targets Based on Cap Model and Penetration Resistance Analysis

为了获得弹丸高速侵彻混凝土介质的阻力方程,提出了一种基于混凝土盖帽模型的球形动态空腔膨胀模型。利用一般形式的状态方程和屈服准则描述混凝土材料的动态力学特性,获得了通用混凝土球形空腔膨胀模型的动态响应表达式。通过引入Dracker-Prager Cap屈服模型,在新的空腔膨胀模型中考虑了混凝土高压下的屈服软化特性。计算结果表明:采用带剪切饱和的Mohr-Coulomb屈服准则与Tresca屈服准则推导出的阻力方程在高速阶段与盖帽模型差别较大。实验结果证明:基于盖帽模型的球形空腔膨胀模型因考虑混凝土高压屈服软化特性与实验结果具有更好的一致性。

In order to obtain the resistance equations of high-velocity projectile penetration into concrete targets, a dynamic spherical cavity-expansion model based on cap model is proposed. The general dynamic response expressions of concrete, which are applied to all kinds of spherical cavity expansion model, are obtained by describing the dynamic mechanical behaviors of concrete material with general equa- tion of state and yield criterion. Yield softening properties of concrete under high pressure are considered in the proposed cavity expansion model by introducing the Drucker-Prager cap model. The calculated re- suits show that the resistance equations of high velocity stage derived using Mohr-Coulomb yield criterion with shear saturation and Tresca criterion are great different from those derived using the cap model. The predictions obtained from the cap model are in good agreement with experimental data.