弹丸冲击贯穿有限厚混凝土材料靶板的背面成坑效应  

Rear face crater-forming of a limited-thickness concrete target due to projectile penetrating

作　　者：纪冲[1,2] 龙源[1] 高振儒[1] 周望远[3] 

机构地区：[1]解放军理工大学 [2]北京理工大学爆炸科学与技术国家重点实验室 [3]中国人民解放军75735部队

出　　处：《振动与冲击》2013年第4期85-89,101,共6页Journal of Vibration and Shock

基　　金：北京理工大学爆炸科学与技术国家重点实验室开放基金资助项目(KFJJ03-5)

摘　　要：弹丸冲击贯穿有限厚混凝土靶板后,靶板背面有大块的混凝土剥落,形成近似的锥形坑。为了研究背面弹坑半锥角θ这一作为混凝土靶板贯穿后破坏范围问题研究中的重要参量,将贯穿问题等效为轴对称条件下的冲切破坏问题。采用双剪应力三参数强度准则及刚塑性模型,得到了极限应力圆的包络线方程,给出了轴对称破坏机构,进而求得θ值的表达式。理论计算结果与数值模拟结果、实验数据三者之间吻合度较好。研究表明,θ值由混凝土材料抗压强度与抗拉强度比值决定。基于上述研究,提出在混凝土中掺加钢纤维以提高有限厚靶板抗贯穿能力的实际方法,并进行了弹道实验。实验结果表明,贯穿破坏后靶板碎片的数量及θ大幅降低,显示了高含量异型钢纤维混凝土在抗贯穿方面的适用性。Tests for projectile penetrating limited-thickness concrete target revealed that concrete chunks spall off from the rear face of the target and a conical crater forms in the process of penetration. The determination of the cone crack angle θ in a concrete target subjected to a projectile impact is important when assessing the level of the damage in the target. The perforation failure of concrete slab was simplified as a problem of punching. With the twin-shear stress three-parameter strength criterion and a rigid-plastic model, an axial symmetrical failure mechanism was given and the failure envelope of stress circle was found to be two straight lines. Then the expression of θ was obtained. The study showed that θ is controlled by the ratio of the compressive strength to tensile strength of the concrete material. Based on the above theoretical analysis, the approach to improve anti-perforation performances of targets by adding steel-fiber into concrete was proposed. Ballistic experiments were performed by using a Ф12.7mm ballistic gun. The experiments showed that the quantity and scattering angle of the target debris decrease obviously; a steel-fiber reinforced concrete with high deformed steel-fiber volume fraction is effective for anti-perforation.

关 键 词：爆炸力学 混凝土板 冲击贯穿 弹坑半锥角 双剪应力三参数强度准则 

分 类 号：O385[理学—流体力学] TU455[理学—力学]