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Measurement of dynamic fracture toughness and failure behavior for explosive mock materials
Pengwan CHEN, Zhongbin ZHOU, Shaopeng MA, Qinwei MA, Fenglei HUANG
《机械工程前沿(英文)》 2011年 第6卷 第3期 页码 292-295 doi: 10.1007/s11465-011-0237-8
In this work, a pre-cracked semi-circular shaped explosive simulant was loaded using a split Hopkinson pressure bar (SHPB). A high-speed camera was used to capture the deformation and fracture process of the specimen in situ. The digital images were processed using the digital image correlation (DIC) method. Next, full displacement and strain fields were obtained. The displacement vector field shows that the specimen fractured under tensile stress action. The strain field can be used to predict the crack propagation. Results show that the method of combined DIC and SHPB is effective to study the dynamic deformation and fracture behavior of explosive simulants. In addition, the specimen was loaded using a drop weight. The fracture toughness of the specimen was preliminary measured.
关键词: digital image correlation polymer bonded explosive simulant split Hopkinson pressure bar (SHPB) semicircular bending test deformation fracture toughness
李杰,王明洋,张宁,范鹏贤
《中国工程科学》 2013年 第15卷 第5期 页码 71-79
深部岩体非线性力学行为是目前岩石力学界研究的重点和难点,研究的困难在于在很大的动力变形与破坏情况下如何阐述岩体的性质。本文通过对深部围岩变形破坏机理、深部岩体动力破坏过程中的基本问题(时间效应、断裂损伤描述等)以及深部岩体特征科学现象(分区破裂、岩爆理论)等方面的研究成果进行梳理和总结,指出深部岩体力学问题是有效的四维空间问题,是在开挖寿命尺度上应力状态的演化,对深部围岩变形破坏机理的研究必须要建立与时间、空间有关的岩石性质的概念。目前要揭示深部岩体卸荷状态下真实的变形与破坏过程,必须继续在连续介质力学框架内研究基于微、细观物理力学的理论,在强度理论中引入时间参数作为塑性流动和破坏过程的特征,并采用合理的手段描述岩体的断裂损伤,岩爆和分区破裂是一个科学问题的两个现象,应当用统一的理论来解释和模拟,本文研究成果可为今后的研究工作指明方向。
A. SHAFIEI
《结构与土木工程前沿(英文)》 2018年 第12卷 第4期 页码 527-535 doi: 10.1007/s11709-018-0450-1
关键词: peridynamics inclined crack dynamic fracture crack branching
Genghuang HE, Xianli LIU, Fugang YAN
《机械工程前沿(英文)》 2012年 第7卷 第3期 页码 329-334 doi: 10.1007/s11465-012-0303-x
The dynamic mechanical characteristics of excessively heavy-duty cutting were analyzed based on the cutting experiments with 2.25Cr-1Mo-0.25V steel used in hydrogenated cylindrical shells. By investigating the influence of dynamic mechanical characteristics on the tools’ failure in limited heavy-duty cutting processes, the model of dynamic shearing force in the cutting area was established. However, the experimental results showed that the dynamic shear flow stress in the cutting area greatly influenced the tools’ fatigue. The heavy-duty cutting tool was damaged in the form of a shearing fracture. Through a comprehensive analysis of the theory, the critical condition of the tools’ fracture under extreme loading was established.
关键词: extreme loading cutting shear flow stress dynamic cutting force fatigue fracture
张宝,丁淳彤,刘宝华,陈雪莲
《中国工程科学》 2003年 第5卷 第3期 页码 44-50
利用飞轮式Hopkinson拉杆实验技术对钨质量分数为93% 的钨合金在-50~100℃温度范围、应变率ε=102~103s-1区间的动态拉伸性态进行了测试,提供了相应的σ-ε曲线和最大拉伸失效应变,并以此为依据建立了该合金动态拉伸行为的本构关系,提出了该合金受动载发生塑性失稳以致发生拉断的判据。利用断口分形分析理论,对试件拉伸断口微观特征所作的分析和对宏观力学性态实验所作的结论给予了有力的支持。
Tests on impact effect of partial fracture at steel frame connections
CHEN Yiyi, BIAN Ruoning
《结构与土木工程前沿(英文)》 2008年 第2卷 第4期 页码 295-301 doi: 10.1007/s11709-008-0049-z
关键词: structural fracture natural fracture progressive high-frequency
Effect of fly ash replacement level on the fracture behavior of concrete
Mahdi AREZOUMANDI, Jeffery S. VOLZ
《结构与土木工程前沿(英文)》 2013年 第7卷 第4期 页码 411-418 doi: 10.1007/s11709-013-0228-4
Computational modeling of fracture in concrete: A review
Luthfi Muhammad Mauludin, Chahmi Oucif
《结构与土木工程前沿(英文)》 2020年 第14卷 第3期 页码 586-598 doi: 10.1007/s11709-020-0573-z
关键词: concrete fracture macroscopic micromechanical heterogeneity
Computational modeling of fracture in capsule-based self-healing concrete: A 3D study
《结构与土木工程前沿(英文)》 2021年 第15卷 第6期 页码 1337-1346 doi: 10.1007/s11709-021-0781-1
关键词: 3D fracture self-healing concrete spherical cohesive elements heterogeneous
Evaluating the material strength from fracture angle under uniaxial loading
Jitang FAN
《结构与土木工程前沿(英文)》 2019年 第13卷 第2期 页码 288-293 doi: 10.1007/s11709-018-0480-8
A dimensional analysis on asphalt binder fracture and fatigue cracking
Qian ZHAO, Zhoujing YE
《结构与土木工程前沿(英文)》 2018年 第12卷 第2期 页码 201-206 doi: 10.1007/s11709-017-0402-1
肖红飞,何学秋,冯涛,王恩元
《中国工程科学》 2005年 第7卷 第11期 页码 81-86
为了更好地应用非接触电磁辐射方法预测预报煤岩灾害动力现象的危险性,借助于力电耦合方程计算出在天线的各个朝向电磁辐射信号的变化规律及对某一个固定监测点结果的比较,就可以确定出某一个监测点电磁辐射信号的最佳监测方向以及应力变化最大(即危险性最大)的方向;在巷道掘进过程中进行巷道迎头电磁辐射动态监测时,天线测定的位置应该放置在巷道高度方向的中部,并对着煤层层理方向,通过不断改变天线朝向来监测巷道迎头和两帮煤岩层的突出危险性;可以通过应力场数值模拟得出的应力集中区来确定有效预测距离的范围。现场电磁辐射信号测定结果表明,利用力电耦合研究煤岩灾害动力现象危险性预测中危险区域的定向定位是可行的。
Experimental research on ductile fracture criterion in metal forming
Song YU, Weiming FENG
《机械工程前沿(英文)》 2011年 第6卷 第3期 页码 308-311 doi: 10.1007/s11465-011-0233-z
Ductile fracture criterion is key limitation parameter in material forming. Accuracy predicting surface and internal failure in plastic deformation process affects on the technology design of workpiece and die greatly. Tension, compression, torsion and shearing test on 45# steel are utilized for providing the experimental values of the critical values at fracture, and 11 widely used ductile fracture criterion are selected to simulate the physical experiments and their relative accuracy for predicting and quantifying fracture initiation sites are investigated. The comparing results show that metal forming process under high triaxiality can be estimated successively using both Normalized Cockcroft-latham and the Brozzo ductile fracture criteria, but the Ayada and general Rice-Tracey model work very well for the low triaxiality cases.
关键词: ductile fracture criteria metal forming process material experiment stress triaxiality
《医学前沿(英文)》 2022年 第16卷 第3期 页码 496-506 doi: 10.1007/s11684-021-0828-7
A concise review about fracture assessments of brittle solids with V-notches
Hsien-Yang YEH, Bin YANG
《结构与土木工程前沿(英文)》 2019年 第13卷 第2期 页码 478-485 doi: 10.1007/s11709-019-0520-z
A concise review of recent studies about the fracture assessments of elastic brittle solid materials containing V-notches is presented. In this preliminary and brief survey, elastic stress distributions in V-notched solids are discussed first. The concept of notch stress intensity factor is introduced. Combine the digital image correlation method with numerical computation techniques to analyze the stress distribution near the notches. Fracture criteria such as strain energy density, J-integral, theory of critical distance are used.
标题 作者 时间 类型 操作
Measurement of dynamic fracture toughness and failure behavior for explosive mock materials
Pengwan CHEN, Zhongbin ZHOU, Shaopeng MA, Qinwei MA, Fenglei HUANG
期刊论文
Dynamic crack propagation in plates weakened by inclined cracks: an investigation based on peridynamics
A. SHAFIEI
期刊论文
Research on the dynamic mechanical characteristics and turning tool life under the conditions of excessively
Genghuang HE, Xianli LIU, Fugang YAN
期刊论文
Effect of fly ash replacement level on the fracture behavior of concrete
Mahdi AREZOUMANDI, Jeffery S. VOLZ
期刊论文
Computational modeling of fracture in concrete: A review
Luthfi Muhammad Mauludin, Chahmi Oucif
期刊论文
Hybrid deep learning model for risk prediction of fracture in patients with diabetes and osteoporosis
期刊论文