刚性弹正侵彻随机骨料混凝土靶的弹道偏转规律分析

针对弹体可能受到非对称力作用从而发生弹道偏转的问题，对刚性弹正侵彻随机骨料混凝土靶的弹道偏转规律进行分析。采用混泥土细观模型，运用 LS-DYNA 显式动力计算软件，对刚性弹正侵彻随机骨料混凝土靶进行数值模拟。以弹体偏转角度为指标，重点考虑混凝土靶的骨料/砂浆强度、弹体侵彻速度等因素，讨论其对弹体正侵彻条件下弹道偏转的影响规律。结果表明：根据混凝土的材料特性，可认为砂浆和骨料共同对正侵彻弹体提供轴向阻力，而随机非均匀的骨料作用力与砂浆阻力之差则提供导致其偏转的侧向力；弹道偏转角度随混凝土砂浆强度减小而增大，相反地，随骨料强度增加而增大；当名义抗压强度较小时，弹体偏转对砂浆强度变化的敏感度显著大于骨料强度变化的影响；在刚性弹假设下，弹道随着弹体侵彻速度增加而更加稳定，即偏转角随着靶速度增加而减小；但若弹体非刚性假设，越高速度侵彻，越容易变形破坏，则越容易偏转且容易出现“J”弹道。

Analysis on Ballistic Trajectory Deflexion of Rigid Projectile Normal Penetrating into Random-aggregate Concrete Targets

The projectile will be subjected to asymmetric force even if the rigid projectile normal penetrating into the concrete due to the random factor of concrete, which can produce the ballistic trajectory deflection. In the paper, the meso-scopic model of the concrete is constructed, and by means of the explicit dynamic software of the LS-DYNA, the numerical simulation of a rigid projectile normal penetrating into random-aggregate concrete targets is conducted. Taking the projectile deflexion angle as the index, the influences of the strengths of the aggregate/mortar and the initial striking velocity on the penetration are discussed. The results show that: according to material characteristics of concrete, the mortar and aggregate provide normal penetration projectile with axial resistance, the difference of random non-uniform aggregate acting force and mortar resistance provides projectile with deflexion lateral force. The trajectory deflexion angle will become larger when concrete mortar intensity decreases, on the contrary, the trajectory deflexion angle will become smaller when aggregate intensity increases. Under rigid projectile hypothesis, trajectory will be more stable when projectile penetration speed increases, that is deflexion angle will decrease when target speed increases. If under non rigid projectile hypothesis, the higher speed penetration will cause easier distortion damage, and it will cause deflexion and “J” type trajectory.