{"title":"Crack growth stabilization in the eccentric three-point end-notched flexure test of solid wood using side-grooved samples","authors":"Hiroshi Yoshihara, Makoto Maruta","doi":"10.1016/j.engfracmech.2024.110605","DOIUrl":null,"url":null,"abstract":"<div><div>A three-point eccentric end-notched flexure (3EENF) test was conducted on Sitka spruce to characterize the Mode II resistance curve (<em>R</em>-curve). To extend the range for stabilized crack growth, grooves were cut along both side surfaces of the sample to reduce the region around the neutral axis. The <em>R</em>-curve was determined by varying the initial crack lengths, and fracture toughness values were measured at both the onset and during growth. Additionally, the effect of side grooves on stabilizing crack growth in the 3EENF test was investigated by comparing numerical simulation results with those from four-point end-notched flexure (4ENF) tests. The grooves effectively stabilized crack growth, and the stabilization range was equivalent to that of the 4ENF test when the initial crack length was appropriately determined. The grooved sample exhibited behavior indicative of a longer crack than the actual length.</div></div>","PeriodicalId":11576,"journal":{"name":"Engineering Fracture Mechanics","volume":"311 ","pages":"Article 110605"},"PeriodicalIF":4.7000,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Engineering Fracture Mechanics","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0013794424007689","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MECHANICS","Score":null,"Total":0}
引用次数: 0
Abstract
A three-point eccentric end-notched flexure (3EENF) test was conducted on Sitka spruce to characterize the Mode II resistance curve (R-curve). To extend the range for stabilized crack growth, grooves were cut along both side surfaces of the sample to reduce the region around the neutral axis. The R-curve was determined by varying the initial crack lengths, and fracture toughness values were measured at both the onset and during growth. Additionally, the effect of side grooves on stabilizing crack growth in the 3EENF test was investigated by comparing numerical simulation results with those from four-point end-notched flexure (4ENF) tests. The grooves effectively stabilized crack growth, and the stabilization range was equivalent to that of the 4ENF test when the initial crack length was appropriately determined. The grooved sample exhibited behavior indicative of a longer crack than the actual length.
对锡特卡云杉进行了三点偏心端部缺口弯曲(3EENF)试验,以确定模式 II 阻力曲线(R 曲线)的特征。为了扩大稳定裂纹生长的范围,沿着样品的两侧表面切割了凹槽,以缩小中性轴附近的区域。通过改变初始裂纹长度来确定 R 曲线,并在裂纹开始和生长过程中测量断裂韧性值。此外,通过比较数值模拟结果和四点末端缺口挠曲(4ENF)试验结果,研究了侧槽对稳定 3EENF 试验中裂纹生长的影响。凹槽有效地稳定了裂纹的生长,在适当确定初始裂纹长度的情况下,稳定范围与 4ENF 试验相当。开槽样品表现出的裂纹比实际长度更长。
期刊介绍:
EFM covers a broad range of topics in fracture mechanics to be of interest and use to both researchers and practitioners. Contributions are welcome which address the fracture behavior of conventional engineering material systems as well as newly emerging material systems. Contributions on developments in the areas of mechanics and materials science strongly related to fracture mechanics are also welcome. Papers on fatigue are welcome if they treat the fatigue process using the methods of fracture mechanics.