弹丸对混凝土薄板的冲击破坏效应

DAMAGE EFFECT OF THIN CONCRETE SLABS SUBJECTED TO PROJECTILE IMPACT

介绍高速弹丸冲击混凝土薄板后所产生的贯穿破坏效应,通过模型试验、数值模拟和量纲理论分析,取得了三者吻合较好的结果,并导出了计算弹丸穿透混凝土薄板后残余速度的经验公式。通过弹丸撞击有限厚度钢筋混凝土靶板的模型试验,获得了有关靶板冲击破坏的宏观图象及弹丸贯穿靶板后的残余速度。介绍了非线性三维动力有限元程序和混凝土材料的脆性损伤模型,对弹丸冲击效应试验中的靶板破坏过程进行了数值模拟,通过数值模拟计算,形象地再现了弹丸高速冲击作用下,钢筋混凝土靶板发生贯穿破坏的物理过程,数值模拟结果与试验中靶板的实际破坏图象十分吻合。通过量纲分析,得出了描述钢筋混凝土板冲击破坏效果各参数之间的无量纲关系,利用现场试验数据进行回归,导出了贯穿条件下的弹丸余速计算公式。

Perforation damage effects of thin concrete slabs produced by impact of projectile at high velocity are studied. Model test, numerical simulation, and dimension theory are employed to analyze the damage effects and the results of the three methods are well consistent. Empirical formula is derived to calculate residual velocity of projectile perforating through the thin concrete slabs. The macroscopic damage images of reinforced concrete slabs under impact effect are obtained through model test, and the residual velocity of the projectile are gained from the tests. Three-dimensional nonlinear dynamic finite element program and the brittleness damage model of concrete are introduced. The numerical simulation of damage process of experimental target slabs is accomplished. The physical processes such as penetration perforation and impact perforation of reinforced concrete slabs subjected to projectile with high speed are displayed visually. The simulation results fit well with the experimental damage image. Through dimension analysis, the dimensionless relationship between all parameters that influence the impact damage effect of reinforced concrete slabs are achieved. Regressive analyses of test data are carried out to obtain the calculation formulae for projectile residual velocities under the condition of penetration perforation or impact perforation.