CAJ | 학술논문

在内部爆炸冲击波载荷作用下,爆炸容器的动态断裂是进行爆炸容器安全评估和失效分析的基础.为了研究爆炸容器的动态断裂特征,进行圆柱钢壳在中心装药的爆炸加载实验,采用非线性动力有限元分析程序LS-DYNA分析圆柱钢壳的弹塑性动力响应,研究圆柱钢壳的宏观变形和断口的宏观、细观形貌,分析圆柱钢壳的断裂模式及断裂机理.结果表明,圆柱钢壳纵向断口具有微孔聚集型剪切韧窝断裂特征,呈现出微孔聚集型剪切韧性断裂模式.内部爆炸冲击波加载下圆柱钢壳因径向膨胀发生动态塑性变形,产生剪切带,由于剪切带的软化效应而成为优先断裂通道,剪切带和环向拉应力的共同作用是形成微孔聚集型剪切韧窝断裂这种混合韧性断裂模式的原因.
재내부폭작충격파재하작용하,폭작용기적동태단렬시진행폭작용기안전평고화실효분석적기출.위료연구폭작용기적동태단렬특정,진행원주강각재중심장약적폭작가재실험,채용비선성동력유한원분석정서LS-DYNA분석원주강각적탄소성동력향응,연구원주강각적굉관변형화단구적굉관、세관형모,분석원주강각적단렬모식급단렬궤리.결과표명,원주강각종향단구구유미공취집형전절인와단렬특정,정현출미공취집형전절인성단렬모식.내부폭작충격파가재하원주강각인경향팽창발생동태소성변형,산생전절대,유우전절대적연화효응이성위우선단렬통도,전절대화배향랍응력적공동작용시형성미공취집형전절인와단렬저충혼합인성단렬모식적원인.
Dynamic fracture of explosion containment vessels(ECVs) subjected to internal blast loads is the foundation for conducting safety assessment and failure analysis of ECVs.The experiments were carried out to investigate dynamic fracture characteristics of cylindrical steel shells subjected to internal blast loadings at the centers.The elastic-plastic response of cylindrical steel shells was conducted using nonlinear dynamic finite element analysis(FEA) code LS-DYNA.The fracture mode and fracture mechanism of a cylindrical shell were specially studied through analysis of deformation, macrographs and mecrographs of fracture surface and elastic-plastic response.The results show that the axial direction fracture surface of the cylindrical steel shell exhibits a mixed ductile fracture mode with shearing dimple by micro-void coalescence.Dynamical ductility deformations appear and the shear bands form when the cylindrical steel shell expands under internal blast loading.The cylindrical steel shell fractures preferentially along the shear bands due to its softening effect.The fracture mechanism is that the shear bands tear under tensile circumferential stress.The shear bands and the tensile circumferential stress dominate the final fracture mode.The fracture mode is of the ductile fracture.