Theoretical and Applied Fracture Mechanics最新文献

{"title":"Propagation and fracture mechanism of an internal crack in brittle solid based on 3D-ILC under uniaxial tension","authors":"Yunfei Wang ,&nbsp;Haijun Wang ,&nbsp;Zhende Zhu ,&nbsp;Jihong Yu","doi":"10.1016/j.tafmec.2025.105019","DOIUrl":"10.1016/j.tafmec.2025.105019","url":null,"abstract":"<div><div>Owing to the low tensile strength of rocks, internal crack expansion under tensile loading is highly susceptible to causing rock engineering failure without warning. In order to reveal the propagation and fracture mechanism of 3D internal cracks under tensile loading, uniaxial tensile tests. numerical simulations were carried out in this study using the 3D-ILC (3D-internal laser-engraved crack) method for prefabricated 3D internal cracks inside transparent rock-like materials. The results indicate that: under axial tension, the crack propagation surface is “S” shaped from the inside to the outside through the outer surface of the specimen, near the left and right side boundaries of the crack surface in the principal max tensile stress is approximately horizontal; According to the distribution and direction of the Wallner lines of the fracture surface, it is known that the prefabricated crack firstly propagates in the ring under the action of uniaxial tension and then changes into a wave shape to propagate to the transverse boundaries on both sides; The trend of crack propagation under uniaxial tension at different inclination angles was basically the same, and the relationship between <em>K</em>_II/<em>K</em>_I and crack deflection angle is revealed by mutual verification of the theoretical formula of energy release rate and numerical simulation results, i.e., the pre-crack inclination angle increases, <em>K</em>_II/<em>K</em>_I increases subsequently, and the crack deflection angle also increases. The research findings will serve as experimental and numerical references for studies on the propagation and fracture mechanism of internal cracks under tensile loading conditions across a spectrum of brittle materials, including rocks.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"139 ","pages":"Article 105019"},"PeriodicalIF":5.0,"publicationDate":"2025-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144177838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Damage and energy evolution characteristics of pre-cracked sandstone under multi-stage amplitude-increasing cyclic loading","authors":"Jun Xu,&nbsp;Shihe Sun,&nbsp;Sen Luo","doi":"10.1016/j.tafmec.2025.105011","DOIUrl":"10.1016/j.tafmec.2025.105011","url":null,"abstract":"<div><div>To systematically investigate the damage evolution and energy dissipation mechanisms associated with rock fracture induced by cyclic disturbance, a series of multi-stage amplitude-increasing cyclic loading tests are conducted on red sandstone specimens containing elliptical pre-existing flaws. The results indicate that, under low-cycle fatigue loading, the peak stress of red sandstone specimens shows a V-shaped variation with increasing defect inclination, with a minimum-to-maximum difference of 26.3 %. In contrast, the peak stress exhibits a W-shaped variation with increasing defect size, with a difference of 18.9 %. Under low-cycle fatigue loading, the elastic modulus exhibits significant hardening and can be modeled accurately with a quadratic function. Furthermore, the evolution of damage with respect to the fatigue life ratio (<em>N</em>/<em>N</em>_f, where <em>N</em> represents the current cycle count and <em>N</em>_f denotes the total number of cycles) can be categorized into three stages: an initial rapid increase stage (0 ≤ <em>N</em>/<em>N</em>_f &lt; 0.2), a middle steady increase stage (0.2 ≤ <em>N</em>/<em>N</em>_f ≤ 0.8), and a late rapid increase stage (0.8 &lt; <em>N</em>/<em>N</em>_f ≤ 1). Additionally, a one-dimensional constitutive equation describing the fatigue damage evolution of red sandstone is established. Energy calculation results demonstrate that both dissipated energy and elastic strain energy exhibit a trend of slow growth followed by sharp increases during the progression of fatigue life ratio. This change can be quantitatively characterized using an exponential function model. The ratio <em>K</em>, defined as the dissipated energy (density) to elastic strain energy (density), remains consistently below 0.7 throughout the evolution of low-cycle fatigue damage. It exhibits three distinct stages of variation as the fatigue life ratio increases. These research findings not only enhance the understanding of rock mass failure mechanisms induced by cyclic disturbances but also provide critical experimental evidence and theoretical support for the design, construction, and long-term stability assessment of deep rock mass engineering.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"139 ","pages":"Article 105011"},"PeriodicalIF":5.0,"publicationDate":"2025-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144168303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating fracture toughness distributions of laser cladding repaired hydrogenation reactors by spherical indentation tests (SITs)","authors":"Tairui Zhang ,&nbsp;Rutai Yue ,&nbsp;Xin Ma ,&nbsp;Zhiqiang Ge ,&nbsp;Alexander Kren ,&nbsp;Xiaochao Liu","doi":"10.1016/j.tafmec.2025.105013","DOIUrl":"10.1016/j.tafmec.2025.105013","url":null,"abstract":"<div><div>Laser cladding repairing provides reliable technical support for the remanufacturing of hydrogenation reactors. However, its repair quality can be significantly affected by process parameters, material aging, and a variety of other factors, urgently demanding an in-situ evaluation method to ensure service reliability of remanufactured hydrogenation reactors. In this case, this study provides an extensive experimental investigation on the fracture toughness predictions by spherical indentation tests (SITs). Firstly, SIT-based fracture toughness predictions are conducted on repaired specimens under optimal process parameters, which indicates significant ductile-to-brittle transitions can be observed in different regions of repaired specimens, together with obvious initial damage existing in both the cladding zone and interface. These factors significantly impact the prediction accuracy of <em>meso</em>-damage mechanics-based models, while the critical stress-critical strain criterion demonstrates superior capability in predicting ductile-to-brittle transitions across different zones. Subsequently, the critical stress-critical strain criterion is employed to investigate the fracture toughness distributions under different process parameters and aging status. It is found that compared to conventional large-scale sampling, the localized characteristics enable SITs providing more precise acquisition of fracture toughness distribution, thus facilitates identification and evaluation of the weakest part of repaired specimens.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"139 ","pages":"Article 105013"},"PeriodicalIF":5.0,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144135004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A new mixed mode I/II fracture test specimen considering the influence of cracks and holes","authors":"Yu Zhao ,&nbsp;Qian Cao ,&nbsp;Shuang Dang ,&nbsp;Chaolin Wang ,&nbsp;Kun Zheng ,&nbsp;Zhongqian Chen ,&nbsp;Wei Tang","doi":"10.1016/j.tafmec.2025.105014","DOIUrl":"10.1016/j.tafmec.2025.105014","url":null,"abstract":"<div><div>This study presents a novel testing specimen for mixed-mode I/II fracture characterization in cracked-perforated materials commonly found in pipelines and tunnels. The improved semi-circular bend (ISCB) specimen incorporates a semi-ring geometry with a centrally located hole and prefabricated radial crack, enabling accurate simulation of crack-hole interactions under structural loading conditions. Through finite element analysis, we systematically quantified critical fracture parameters including mode I/II stress intensity factors and T-stress. Experimentally, three-point bending tests on PMMA ISCB specimens using a universal testing machine quantified crack initiation angles and fracture toughness values. Comparative analyses of classical fracture criteria revealed the generalized maximum tangential stress (GMTS) criterion’s superior predictive capability. The GMTS criterion achieved the most accurate fracture angle predictions with &lt;5 % deviation in average fracture toughness estimates.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"139 ","pages":"Article 105014"},"PeriodicalIF":5.0,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144168795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stress ratio effect on fatigue crack growth behavior for steels related to yield-to-tensile strength ratio and fracture toughness","authors":"Anye Xu ,&nbsp;Yipin Wan ,&nbsp;Bolun Li ,&nbsp;Xing Yang ,&nbsp;Min Ye ,&nbsp;Xuding Song","doi":"10.1016/j.tafmec.2025.105015","DOIUrl":"10.1016/j.tafmec.2025.105015","url":null,"abstract":"<div><div>Fatigue crack growth (FCG) behavior related to stress ratio (<em>R</em>) is critical for assessing material durability. Based on fracture mechanics theory and asymptotic analysis, a progressive FCG rate model is derived by incorporating <em>R</em>, yield-to-tensile strength ratio, and fracture toughness by linking asymptotic limits of FCG rate curve with the <em>R</em>-dependent relationship between fracture toughness and fatigue crack growth threshold. Additionally, lognormal distribution theory is introduced for probabilistic analysis to consider the inevitable scatter in FCG measurements caused by material heterogeneity and testing errors. Validation results show that the proposed model can accurately describe FCG behavior for long cracks in near-threshold, Paris, and unstable stages at varying <em>R</em> from 0 to 0.6 for steels.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"139 ","pages":"Article 105015"},"PeriodicalIF":5.0,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144134999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation on the dynamic fracture behavior of three-centered circle twin tunnels containing a joint under impact loading","authors":"Jingkang Feng,&nbsp;Lei Zhou,&nbsp;Fukuan Nie,&nbsp;Jian Hua,&nbsp;Yao Li","doi":"10.1016/j.tafmec.2025.105010","DOIUrl":"10.1016/j.tafmec.2025.105010","url":null,"abstract":"<div><div>This paper explored the dynamic failure mechanism of three-centered circle twin tunnels under dynamic loads and a joint is located in the surrounding rock mass, a combined method of model tests and numerical simulations is adopted in this paper. Dynamic fracture tests were conducted using a split-Hopkinson pressure bar (SHPB) apparatus by employing a model of a three-centered circle of twin tunnels. The dynamic fracture behavior of three-centered circle twin tunnels was analyzed by using a digital image correlation (DIC) method. Meanwhile, numerical simulations were carried out using the RHT constitutive model in LS-DYNA software to reveal the stress distribution law and the influence of the concrete initial support structure. The fracture extends in the direction of the stress wave propagation and converges at the tunnel shoulder region, some fractures extend along the stress wave direction at the joint tips and converge at the tunnel shoulders. Based on the dynamic mechanical behavior analysis, pre-joint significantly reduce the dynamic compressive strength (DCS) and elastic modulus of the twin tunnels. At low inclination angles (0°–30°), especially at 0°, the DCS and dynamic elastic modulus experience a reduction of 16.89 % and 13.08 GPa, respectively. With the rise of the inclination angle, the DCS and dynamic elastic modulus exhibit a progressive recovery trend, and are close to the level of the specimen without prefabricated cracks at high inclination angles (75°–90°). The dynamic stress concentration factor (DSCF) analysis shows that the increase of support significantly reduces the stress concentration degree at various locations around the tunnel, especially in vulnerable areas, which further improves the stability of the tunnel. When the joint dip angle is from 60° to 90°, crack propagation paths show multi-branch characteristics, and the interaction between tunnels is limited. The DSCF in the tunnel crown and bottom areas is the key factor initiating failure. The concrete initial support significantly enhances the twin tunnels’ resistance to dynamic disturbance load, reducing the normalized damage volume by up to 37.37%.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"139 ","pages":"Article 105010"},"PeriodicalIF":5.0,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144138097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of bedding orientation and loading rate on fracture behaviors in coal: Analysis of experiments","authors":"Wei Wang ,&nbsp;Bingchao Zhao ,&nbsp;Yixin Zhao","doi":"10.1016/j.tafmec.2025.105012","DOIUrl":"10.1016/j.tafmec.2025.105012","url":null,"abstract":"<div><div>To explore the fracture behaviors in coal, laboratory tests are conducted on semi-circular bend specimens with various pre-crack inclinations and bedding orientations subjected to quasi-static and dynamic loadings, respectively. Considering the bedding distribution, the coal is regarded as a transversely isotropic media, its elastic properties are derived from uniaxial compression tests. The critical stress intensity factors are determined using an experimental–numerical method. Findings indicate that the variations of critical stress intensity factors are significantly co-affected by pre-crack inclination, bedding orientation and loading rate. With bedding angle increasing, the planar positional relationship between beddings and loading direction is progressively evolving from orthogonality state to parallelism state, the critical stress intensity factors decline owing to the low cementation strength within beddings. As pre-crack rotates, due to the finite number of angles and strong anisotropy, the variations have no evident regularity. Furthermore, the critical stress intensity factors of coal exhibit sensitivity to loading rate, augmenting with an increase in rate, while anisotropy diminishes. Based on the elastic theory of transversely isotropic body, the conventional fracture criterion, maximum tangential stress, is refined to better describe the fracture onset in coal.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"139 ","pages":"Article 105012"},"PeriodicalIF":5.0,"publicationDate":"2025-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144135000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A phase-field model for stress-assisted hydrogen diffusion and fracture: An Abaqus implementation","authors":"K. Shiva Reddy ,&nbsp;Amirtham Rajagopal ,&nbsp;Timon Rabczuk","doi":"10.1016/j.tafmec.2025.104988","DOIUrl":"10.1016/j.tafmec.2025.104988","url":null,"abstract":"<div><div>Hydrogen dissolved in metals – whether from either internal or external sources – can significantly degrade mechanical properties by interacting with material defects. In the present work, a comprehensive finite element framework for modelling the coupled deformation-diffusion-fracture problem is discussed. A staggered approach is employed to solve the coupled problem, where displacement, crack phase-field, and concentration fields are weakly coupled. A novel implementation of phase-field modelling for hydrogen-assisted fracture is developed within Abaqus/Standard, employing user-defined UEL and UVARM subroutines. The detailed implementation procedure facilitates modelling hydrogen-assisted fracture and similar coupled problems, providing researchers with a practical and accessible computational approach. The finite element code developed for one of the numerical simulations is available at: <span><span>https://github.com/shivareddykondakindi/HED-Abaqus.git</span><svg><path></path></svg></span>.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"139 ","pages":"Article 104988"},"PeriodicalIF":5.0,"publicationDate":"2025-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144154774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural integrity and life assessment of railway and aeronautical components – Review of four case studies","authors":"Aleksandar Sedmak ,&nbsp;Aleksandar Grbović ,&nbsp;Simon Sedmak","doi":"10.1016/j.tafmec.2025.105008","DOIUrl":"10.1016/j.tafmec.2025.105008","url":null,"abstract":"<div><div>Structural integrity and life assessment of railway and aeronautical components, critical for the safety of these two important means of transport, is analysed using four case studies, two for each of them. In respect to railway components, a brief failure analysis of a fractured wheel is presented, with the idea to use this experience to improve structural integrity of wheels in general. Second case study is focused on coupling link used in freight wagons, once again providing failure analysis to improve its safety. Case studies of aeronautical components comprise torque links and High Temperature and Pressure (HTP) casings, as crucial components of airplane landing gear and jet engine, respectively. In both cases residual fatigue life was in focus with an aim to replace damaged torque link with a new one, produced by Additive Manufacturing (AM), and to check if damaged HTP casing can remain in operation for a certain period o time.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"139 ","pages":"Article 105008"},"PeriodicalIF":5.0,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144130802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on the effect of the spalling area and interfacial shear stress on fiber pullout behavior: Experimental and meso-mechanical analysis","authors":"Jiebin Li ,&nbsp;Muyun Liu ,&nbsp;Yanfei Niu ,&nbsp;Jiangxiong Wei ,&nbsp;Qijun Yu ,&nbsp;Dengwu Jiao","doi":"10.1016/j.tafmec.2025.105009","DOIUrl":"10.1016/j.tafmec.2025.105009","url":null,"abstract":"<div><div>This study investigated the pullout behavior of steel fibers with different curing ages (7, 14, 28 days) and inclination angles (0°, 30°, 45°, 60°), assessing the degree of matrix spalling as well as utilizing <em>meso</em>-mechanical model to evaluate the pullout behavior. The pullout load and average bond strength were maximum at 45° for different inclination angles, while the maximum pullout energy occurred at 60°. The spalling area of matrix was less influenced by curing age but was significantly affected by inclination angle, with the maximum spalling area occurring at 60°. An equation was provided to assess the relationship between spalling area and inclination angle. The degradation of interfacial shear stress determined the trend of descending branch (debonding stage), with the shape changing from concave to convex and the curvature of the convex shape gradually increasing with different curing ages and inclination angles. Expanding the value of shape coefficient <span><math><mrow><mi>η</mi></mrow></math></span> from −0.1 to −0.05 and introducing an interfacial enhancement factor <span><math><mrow><mi>b</mi></mrow></math></span> with a range of values from −8 to −2 can effectively evaluate the change of the interfacial shear stress, and the results of the numerical analysis were in agreement with experimental results.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"139 ","pages":"Article 105009"},"PeriodicalIF":5.0,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144177837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}