论文部分内容阅读
为进一步探讨弹体对岩石靶体的侵彻作用机理,基于对岩石材料的八面体剪应力随平均主应力非线性增加特性的考虑,通过增加平均主应力的非线性项对双剪统一强度准则进行改进。分别采用双剪统一强度理论和改进的双剪强度理论作为岩石材料的强度准则,建立了弹体垂直侵彻岩石靶体的动力球形空腔膨胀可压缩弹塑性侵彻模型,提出了考虑侵彻过程中弹头法向和切向摩擦阻力影响的弹体垂直侵彻岩石靶体的阻力计算公式,进而求得了弹体垂直侵彻岩石靶体的深度。理论分析模型的计算结果与常用侵彻经验公式的计算结果以及野外花岗岩侵彻试验数据的对比分析表明:基于改进双剪强度理论所建立的理论分析模型的计算结果与试验数据最为接近,其主要原因是在靶体强度准则中考虑了八面体剪应力的影响。
In order to further explore the penetration mechanism of the projectile on the rock target, based on the consideration of the non-linear increase of the octahedral shear stress of the rock material with the average principal stress, by increasing the non-linear term of the average principal stress, Improve. Using the double shear unified strength theory and the improved double shear strength theory as the strength criterion of rock materials respectively, a dynamical spherical cavity expansion compressible elasto-plastic penetration model with the projectile vertically penetrating the rock target was established, During the process, the resistance of the projectile perpendicularly penetrating the rock target body affected by the warhead normal and tangential frictional resistances is calculated, and the depth of the projectile penetrating the rock target body vertically is obtained. The comparison of the calculated results of the theoretical analysis model with those of the common penetrating experience formula and the experimental data of the field granite penetration shows that the theoretical analysis model established based on the improved double shear strength theory is the closest to the experimental data, The reason is that the influence of octahedral shear stress is taken into account in the target strength criterion.