约束混凝土靶的准静态柱形空腔膨胀理论

针对射弹侵彻约束混凝土靶问题,基于Hoek-Brown(H-B)准则,建立了径向受弹性约束的有限混凝土介质准静态柱形空腔膨胀模型,得到了各种响应模式下的扩孔压力和响应模式转换条件,分析了扩孔过程以及约束效应对扩孔压力和侵彻阻力的影响。结果表明:约束混凝土靶的扩孔压力在扩孔过程中不断变化,约束刚度对响应模式和扩孔压力有显著影响;增大约束刚度可有效提高约束混凝土靶的侵彻阻力,约束混凝土靶的侵彻阻力可比半无限靶提高50%以上。

Quasi-static Cylindrical Cavity-expansion Model for Confined-concrete Targets

Aiming at the problem of projectile penetrating into confined concrete target,a quasi-static cylindrical cavity-expansion model for finite concrete target with radially elastic confinement was established based on the Hoek-Brown (H-B)criterion.The pressure at cavity wall and the transition conditions of response modes were obtained.The influence of cavity expansion process and confinement on pressure at cavity wall was also analyzed.The results show that the pressure at cavity wall and resistance of penetration constantly vary during the process of cavity expansion,and the confinement stiffness has significant effect on response modes and pressure at cavity wall.It can greatly improve penetration resistance of confined concrete to increase confinement stiffness.The penetration resistance of confined concrete target is larger than that of semi-infinite concrete target by 50％.