摘要:
由于侵彻花岗岩试验存在原料获取难度大、费用高的问题，现开展钢筋混凝土与花岗岩靶标等效性研究。本文使用量纲分析与修正补偿法，以剩余速度作为等效前提，获得等效厚度计算方法。依据现有试验研究，使用LS-DYNA软件，结合数值模拟方法，建立弹体中速侵彻靶标的数值模型，以弹体尺寸、速度和靶标厚度为变量设计典型工况，数据拟合得到花岗岩靶体与钢筋混凝土靶体的具体等效设计公式。研究表明：建立的数值仿真模型能够较为准确地模拟出弹体侵彻花岗岩与钢筋混凝土靶体过程中弹体的剩余速度以及靶体的破坏特征；在弹体侵彻过程中，花岗岩靶体相较钢筋混凝土靶体，压实区与隧道区直径更小，裂纹更细、更长、扩展速度更快，靶面上裂纹面积更大，容易形成较大的剥落弹坑；在相同侵彻条件下，花岗岩与等效厚度钢筋混凝土靶体的破坏特征相近，破坏区域均可划分为5个部分；基于量纲分析与补偿修正法获得了弹体在侵彻钢筋混凝土与花岗岩时的无量纲剩余速度函数表达式以及钢筋混凝土与花岗岩靶体的等效厚度公式；拟合得到花岗岩与钢筋混凝土等效靶厚系数为1.69966，并使用等效靶厚系数对靶厚等效设计公式进行验证，原型靶体与模型靶体弹体剩余速度误差不超过5%。研究结果可为弹体中速侵彻岩石靶板的等效设计提供参考。
Abstract:
Due to the challenges associated with material acquisition and high costs in penetration tests on granite targets, research on the equivalence between reinforced concrete (RC) and granite targets has been conducted. This study employs dimensional analysis and a modified compensation method, with the residual velocity as the equivalence criterion, to derive a computational approach for equivalent thickness. Based on existing experimental studies, a numerical model for medium-velocity projectile penetration into targets is established using LS-DYNA software and numerical simulation techniques. By considering projectile dimensions, impact velocity, and target thickness as variables, typical working conditions are designed. Through data fitting, a specific equivalent design formula for granite and reinforced concrete targets is obtained. The results indicate that the developed numerical simulation model accurately captures the residual velocity of the projectile and the failure characteristics of the targets during penetration. In the penetration process, compared to reinforced concrete targets, granite targets exhibit a smaller compaction zone and tunnel diameter, finer and longer cracks with higher propagation speeds, larger crack areas on the target surface, and a tendency to form larger spalling craters. Under identical penetration conditions, the failure characteristics of granite and equivalent-thickness reinforced concrete targets are similar, with both targets exhibiting five distinct failure regions. Using dimensional analysis and the compensation correction method, a dimensionless residual velocity function for projectiles penetrating reinforced concrete and granite targets is derived, along with an equivalent thickness formula for the two target types. The fitted equivalent thickness coefficient between granite and reinforced concrete is determined to be 1.69966. Validation of the equivalent thickness design formula using this coefficient shows that the error in residual velocity between the prototype and model targets does not exceed 5%. The findings of this study provide a valuable reference for the equivalent design of rock targets subjected to medium-velocity projectile penetration. The present work contributes to the field by offering a systematic methodology for substituting
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