基于Ottosen屈服条件的不同强度混凝土空腔膨胀模型及侵彻机理  

Cavity expansion model and penetration mechanism of concrete with different strengths based on the Ottosen yield condition

作　　者：张雪岩 孙凯[1] 李元龙 曾费隐 李国杰 武海军[2] ZHANG Xueyan;SUN Kai;LI Yuanlong;ZENG Feiyin;LI Guojie;WU Haijun(Beijing Aerospace Long March Aircraft Research Institute,Beijing 100076,China;State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology,Beijing 100081,China)

机构地区：[1]北京航天长征飞行器研究所,北京100076 [2]北京理工大学爆炸科学与技术国家重点实验室,北京100081

出　　处：《爆炸与冲击》2023年第9期58-73,共16页Explosion and Shock Waves

基　　金：国家自然科学基金(11572048,11390362)。

摘　　要：针对毁伤与防护领域对深层超硬目标理论研究及工程应用的迫切需求,引入改进的Ottosen屈服条件,对混凝土空腔膨胀过程中的响应分区和边界条件进行优化,求解空腔膨胀的全过程,分析不同强度混凝土响应分区的变化规律;根据空腔边界应力和空腔膨胀速度的关系,建立了弹体侵彻深度计算模型,对弹体侵彻不同强度混凝土工况进行了对比计算,并深入分析了靶体强度对侵彻深度影响的机理。通过与实验数据进行对比发现,改进的空腔膨胀理论对于普通混凝土和高强混凝土均有很好的适用性,可准确计算径向应力与空腔边界速度关系以及侵彻深度。研究结果显示,高强混凝土的弹塑性开裂区范围更大,密实区范围更小,表明了高强混凝土脆性大,材质密实的特点,引入塑性开裂区可以更好地反应侵彻过程中高强混凝土压实时对应速度更高的现象;随着混凝土强度的提高,其屈服包络面变化越来越小,因此混凝土的空腔边界应力增大但变化程度越来越小,导致弹体侵彻深度随速度增加的增量变小。Aiming at the urgent demand for theoretical research and engineering application of deep super hard targets in the field of damage and protection,the response zone and boundary conditions during the cavity expansding process are optimized in this paper based on the improved Ottosen yield condition.The entire process of cavity expansion is solved,the changes in the response zone of concrete with different strengths are analyzed.According to the relationship between cavity boundary stress and cavity expansion velocity,a calculation model of projectile penetration depth is established,and the penetration depth of projectile penetration into concrete with different strengths are calculated.The mechanism of the influence of target strength on penetration depth is also analyzed.The results show that the elastic and plastic cracking zone of high-strength concrete is larger and the compacted zone is smaller,indicating that high-strength concrete is more brittle and compact.And the addition of plastic cracking zone can better reflect the phenomenon of concrete with different strengths in penetration.By comparing with the experimental data,it can be seen that the cavity expansion theory established in this paper has good applicability for normal concrete and high-strength concrete.The relationship between radial stress and cavity boundary velocity and the penetration depth also can be accurately calculated by this theory.With the increase of concrete strength,the difference in the cavity boundary stress of the concrete becomes smaller,resulting in a smaller increase in the penetration depth of the projectile as the velocity increases,and the penetration depth of the projectile decreases and gradually tends to a certain value at the same speed.

关 键 词：Ottosen屈服条件 空腔膨胀理论 高强混凝土 侵彻深度 

分 类 号：O383[理学—流体力学] TU528.01[理学—力学]