摘要
开展了圆柱形爆炸容器逐级加载和破坏实验,根据容器最终的断裂面和微观形貌观测,提出了爆炸容器绝热剪切失效模式。建立了应变率-应变空间内的绝热剪切损伤演化模型,将绝热剪切不同演化阶段的临界状态与宏观的力学条件联系起来,并将这些力学临界条件作为动态失效准则引入到宏观计算程序中,模拟爆炸容器发生绝热剪切的的瞬态过程,模拟结果成功预测了爆炸容器最终的断裂形貌。数值模拟结果还表明,爆炸载荷和率相关失效准则是控制绝热剪切失效模式的2个主要因素,细观初始缺陷往往导致绝热剪切的激发,但对容器最终的失效模式的影响是次要的。当容器在爆炸载荷作用下发生绝热剪切破坏模式时,裂纹(剪切带)扩展速度较快,此时若仍采用整体塑性应变失效准则考察容器的动力响应并作为失效判据,将不能预见材料局部的弱化和破坏。
Destruction tests were performed on a cylindrical explosion containment vessel（ECV） by applying the explosive loads with the increasing charge masses of TNT.An adiabatic shear failure mode for ECVs was presented based on the fracture and the micro-optical observation of the destructed vessel.A damage evolution model for ECVs subjected to adiabatic shear was constructed,where the mechanical conditions including strain rate and strain were linked with the different evolution states of the adiabatic shear bands（ASBs）.And these mechanical conditions were employed in the numerical code as the failure criteria to simulate the transient process of the ASB evolution.The simulated fracture profile shows a good agreement with the experimental result.The simulated result indicates that the rate-dependent critical strain,as well as explosive load,governs the adiabatic shear failure mode.Though the initial material imperfection ignites the ASBs,it has a minor influence on the final fracture profile.For the ECVs with the adiabatic shear failure mode,the crack（or ASB） expands faster than for those with the plastic instability failure mode.
出处
《爆炸与冲击》
EI
CAS
CSCD
北大核心
2012年第2期136-142,共7页
Explosion and Shock Waves
基金
国家自然科学基金项目(51005201
50875236)
中央高校基本科研业务费专项项目~~
关键词
爆炸力学
失效模式
绝热剪切
爆炸容器
mechanics of explosion
failure mode
adiabatic shear
explosion containment vessel
