Miao Yu, Haitao Luo, Hongdi Jing, Hongyuan Li, Shuang Wang
{"title":"Simultaneous determination of dynamic fracture toughness and tensile strength through a single three-point bending test","authors":"Miao Yu, Haitao Luo, Hongdi Jing, Hongyuan Li, Shuang Wang","doi":"10.1007/s11043-023-09639-3","DOIUrl":null,"url":null,"abstract":"<div><p>The fracture process zone (FPZ) has been assumed to activate microcrack evolution and influence the mechanical parameters of the rock specimen. This can be linked to the grain size of the rock specimens located in the path of the crack propagation. However, few studies have considered the effect of the grain distribution on the size of the FPZ, especially under dynamic loadings. In this paper, we analyze the mechanism by which the strain rate and grain distribution affect the FPZ and the dynamic mechanical parameters. We selected three kinds of sandstone specimens to represent the mesostructure heterogeneities characterized by the fractal dimensions. Also, the size of the FPZ can be calculated by the grain size and the dynamic fictitious crack length under the quantified mesostructure heterogeneities and the concept of the box dimension method. Based on the results, the dynamic strength and fracture toughness can be obtained with unknown coefficients. The unknown coefficients were then determined via the dynamic fracture test, in which the processed semicircle bending (SCB) specimens were used for the pendulum hammer-driven split Hopkinson pressure bar (SHPB) apparatus. Finally, the results were validated using the existing experimental methods recommended by the International Society for Rock Mechanics (ISRM). This study provides a valid and simpler method for the simultaneous determination of the dynamic fracture toughness and tensile strength of rock specimens.</p></div>","PeriodicalId":698,"journal":{"name":"Mechanics of Time-Dependent Materials","volume":"28 3","pages":"801 - 815"},"PeriodicalIF":2.1000,"publicationDate":"2023-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Mechanics of Time-Dependent Materials","FirstCategoryId":"88","ListUrlMain":"https://link.springer.com/article/10.1007/s11043-023-09639-3","RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATERIALS SCIENCE, CHARACTERIZATION & TESTING","Score":null,"Total":0}
引用次数: 0
Abstract
The fracture process zone (FPZ) has been assumed to activate microcrack evolution and influence the mechanical parameters of the rock specimen. This can be linked to the grain size of the rock specimens located in the path of the crack propagation. However, few studies have considered the effect of the grain distribution on the size of the FPZ, especially under dynamic loadings. In this paper, we analyze the mechanism by which the strain rate and grain distribution affect the FPZ and the dynamic mechanical parameters. We selected three kinds of sandstone specimens to represent the mesostructure heterogeneities characterized by the fractal dimensions. Also, the size of the FPZ can be calculated by the grain size and the dynamic fictitious crack length under the quantified mesostructure heterogeneities and the concept of the box dimension method. Based on the results, the dynamic strength and fracture toughness can be obtained with unknown coefficients. The unknown coefficients were then determined via the dynamic fracture test, in which the processed semicircle bending (SCB) specimens were used for the pendulum hammer-driven split Hopkinson pressure bar (SHPB) apparatus. Finally, the results were validated using the existing experimental methods recommended by the International Society for Rock Mechanics (ISRM). This study provides a valid and simpler method for the simultaneous determination of the dynamic fracture toughness and tensile strength of rock specimens.
期刊介绍:
Mechanics of Time-Dependent Materials accepts contributions dealing with the time-dependent mechanical properties of solid polymers, metals, ceramics, concrete, wood, or their composites. It is recognized that certain materials can be in the melt state as function of temperature and/or pressure. Contributions concerned with fundamental issues relating to processing and melt-to-solid transition behaviour are welcome, as are contributions addressing time-dependent failure and fracture phenomena. Manuscripts addressing environmental issues will be considered if they relate to time-dependent mechanical properties.
The journal promotes the transfer of knowledge between various disciplines that deal with the properties of time-dependent solid materials but approach these from different angles. Among these disciplines are: Mechanical Engineering, Aerospace Engineering, Chemical Engineering, Rheology, Materials Science, Polymer Physics, Design, and others.