Wanmei Gui , Xiaozhi Hu , Lan Wang , Chao Li , You Zhan , Fei Zhang , Zehua Tian
{"title":"Investigating fracture behaviors of fiber-reinforced warm-mixed recycled SBS modified asphalt mixtures using the DIC and AE techniques under different loading modes","authors":"Wanmei Gui , Xiaozhi Hu , Lan Wang , Chao Li , You Zhan , Fei Zhang , Zehua Tian","doi":"10.1016/j.tafmec.2025.105194","DOIUrl":"10.1016/j.tafmec.2025.105194","url":null,"abstract":"<div><div>To enhance the early-stage crack resistance of warm-mixed recycled asphalt mixtures, various types of reinforcing fibers were incorporated and investigated through a multi-scale analysis. Digital Image Correlation (DIC) and Acoustic Emission (AE), both non-destructive techniques, were utilized to monitor damage evolution in real-time. This study investigates the effects of basalt fiber morphology and fracture loading modes on the fracture resistance and synergistic crack resistance mechanisms of fiber-reinforced warm-mixed recycled SBS modified asphalt mixtures (WRAM-BF). Edge-Notched Disc Bending (ENDB) tests were conducted under mode I, mode III, and mixed mode I/III loading conditions using flocculent and chopped basalt fibers, combined with DIC and AE monitoring techniques. AE signal parameters, including source localization, peak frequency, and ringing counts, were analyzed to characterize the initiation and evolution of internal microcracks. DIC strain field mapping and the damage factor were employed to quantify full-field mesoscale strain distributions and crack propagation. The results indicate that the integration of AE and DIC facilitates a thorough and quantitative assessment of fracture behavior in WRAM-BFs. Specifically, flocculent fibers were found to effectively delay microcrack initiation, whereas chopped fibers significantly suppressed macrocrack propagation under various fracture modes. The findings also offer insights into the toughening mechanisms of fiber–rejuvenator synergy in sustainable asphalt composites.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"140 ","pages":"Article 105194"},"PeriodicalIF":5.6,"publicationDate":"2025-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144988630","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}
Bingyan Wei, Xiongjun He, Zhiyi Tang, Huayi Wang, Ming Zhou
{"title":"Study on the fracture behavior of hybrid fiber-reinforced high-strength concrete single-edge notched beams: Theoretical analysis and experimental verification","authors":"Bingyan Wei, Xiongjun He, Zhiyi Tang, Huayi Wang, Ming Zhou","doi":"10.1016/j.tafmec.2025.105206","DOIUrl":"10.1016/j.tafmec.2025.105206","url":null,"abstract":"<div><div>To investigate hybrid fiber effects on the fracture behavior of high-strength concrete (HSC), three-point bending tests were performed on single-edge notched beams (SENB). These tests evaluated the influence of hybrid fiber types and volume fractions on load-crack mouth opening displacement (CMOD) curves, fracture energy, characteristic length, and fracture toughness. A stress-crack width (<span><math><mrow><mi>σ</mi><mo>-</mo><mi>w</mi></mrow></math></span>) curve for hybrid fiber-reinforced HSC (HFRHSC) was also established using the double-K fracture model and inverse analysis. Results demonstrated that fiber incorporation significantly enhanced concrete fracture behavior and had a significant strengthening and toughening effect. For single-doped wave steel fiber (WSF) reinforcement, increased WSF volume fraction improved fracture behavior. Compared to single-doped WSF, optimal hybridization of fiber types and ratios further enhanced fracture behavior while maintaining high post-cracking load-bearing capacity. A notable discrepancy emerged between the bilinear <span><math><mrow><mi>σ</mi><mo>-</mo><mi>w</mi></mrow></math></span> curve derived from the double-K model and inverse analysis results. The double-K model inadequately captured nonlinear fiber-bridging stress distribution, whereas inverse analysis accurately reconstructed crack evolution control equations, revealing the gradient distribution of fiber-bridging forces in the fracture process zone. This inverse analysis approach more precisely characterized HFRHSC’s post-cracking pseudo-hardening behavior and multi-stage load-transfer mechanisms.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"140 ","pages":"Article 105206"},"PeriodicalIF":5.6,"publicationDate":"2025-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144925453","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}
Zhongping Yang , Miao Liu , Shunbo Zhang , Yang Gao , Shanmeng Hou
{"title":"Damage evolution and constitutive model of limestone considering fissure angle and wet-dry cycles under axial stress","authors":"Zhongping Yang , Miao Liu , Shunbo Zhang , Yang Gao , Shanmeng Hou","doi":"10.1016/j.tafmec.2025.105212","DOIUrl":"10.1016/j.tafmec.2025.105212","url":null,"abstract":"<div><div>Fissured limestone in the hydro-fluctuation belt of the Three Gorges Reservoir is prone to degradation under wet-dry cycles, posing a significant risk in geologically hazardous regions. However, the damage evolution mechanisms and mechanical response behavior of fissured rock masses under combined wet-dry cycles and axial stress remain poorly understood, and effective non-contact early warning technologies are still lacking. To address this, we conducted microscopic analysis, uniaxial compression testing, and digital image correlation monitoring to investigate the deterioration characteristics of limestone with varying fissure angles and wet-dry cycles. Moreover, we proposed a statistical early-warning method grounded in the divergence rate and statistical characteristics of strain and displacement fields. A piecewise constitutive model incorporating macroscopic, wet-dry cycle and microscopic damage was established incorporating the compaction stage. Results show that wet-dry cycles significantly alter the pore structure and calcite content, and that limestone degradation arises from the combined effects of physical reaction, chemical reaction, and axial stress. Peak stress and elastic modulus increase with fissure angle but decrease with cycle count. The failure mode is jointly influenced by fissure angle and number of wet-dry cycles, with fissure angle playing a dominant role. The statistical indicators and divergence rates of the strain and displacement fields enable identification of three distinct stages of failure: stable, crack propagation, and failure. The model predictions align well with experimental stress–strain curves. This study provides new insight into the damage mechanisms of fissured limestone and offers theoretical support for precursor identification and geohazard mitigation in reservoir environments.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"140 ","pages":"Article 105212"},"PeriodicalIF":5.6,"publicationDate":"2025-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144988633","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":"Fatigue-free cohesive zone model for fatigue delamination prediction in fiber reinforced composite laminates","authors":"Pengcheng Xue, Jian Xiong","doi":"10.1016/j.tafmec.2025.105214","DOIUrl":"10.1016/j.tafmec.2025.105214","url":null,"abstract":"<div><div>This work proposes a Fatigue-free cohesive zone model (F-free model) for predicting fatigue delamination growth in fiber reinforced composite laminates. Unlike traditional empirical approaches that rely on fatigue test calibration, the F-free model is grounded in mechanics and requires only quasi-static delamination data. The formulation combines Timoshenko beam theory with a fatigue cohesive zone model, where the interfacial toughness evolves with crack length to account for the influence of bridging fibers. A proof-stress-inspired method is used to define the cohesive zone endurance limit, eliminating the need for fatigue-specific testing. The model is validated against two benchmark cases. The predicted fatigue delamination growth rates show excellent agreement with experimental data, and the results indicate that the model predictions successfully encompass the full range of observed growth rates. Additionally, the Paris’ law exponents derived from model predictions closely match those obtained from the experimental data. Beyond accuracy, the approach offers physical insight into the mechanical role of fiber bridging, revealing its effect in raising the fatigue threshold and steepening the crack growth curve. Overall, the model provides a robust framework that does not require fatigue data for simulating fatigue delamination growth in fiber reinforced composite laminates.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"140 ","pages":"Article 105214"},"PeriodicalIF":5.6,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144932097","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}
Huidong Cao , Jianfeng Zhao , Ali Arab , Tianyang Du , Shiqi Liu , Chunwei Zhang
{"title":"Effect of strain rate on crack propagation and fracture toughness of the concrete at mode I and mixed mode I/II","authors":"Huidong Cao , Jianfeng Zhao , Ali Arab , Tianyang Du , Shiqi Liu , Chunwei Zhang","doi":"10.1016/j.tafmec.2025.105210","DOIUrl":"10.1016/j.tafmec.2025.105210","url":null,"abstract":"<div><div>Although the fracture toughness of concrete materials has been widely studied at different loading rates, the concrete crack propagation and the failure process, which are of great significance to understand the failure mechanism concrete, have been rarely studied. This study conducts the fracture tests at different loading-rate on Semi-circular bending (SCB) specimens with different pre-notched angles by universal testing machine and Split Hopkinson Pressure Bar (SHPB). Digital Image Correlation (DIC) technology is applied to analyze the fracture process of concrete SCB specimens in detail. A new method has been proposed to determine the coordinated time between the SHPB signal and the history of DIC, thereby determining the crack initiation and termination of concrete. The failure on the concrete surface is mainly interfacial transition zone (ITZ) failure, while inside the concrete, the combined failure of aggregates, mortar, and ITZ constitutes the overall fracture at low loading rate. The results show that the peak load of the specimen and its variability increase with loading rate and pre-notched angle, with variability being more sensitive to pre-notched angle. Additionally, as the loading rate increases, the crack propagation speed also increases. The excessively high loading rates should not be used to achieve the expected fracture mode (mode I and mixed mode I/II), and it will overestimate the real value of the fracture toughness. For specimens with <em>β</em> = 0° and 45°, <span><math><mover><mi>K</mi><mo>̇</mo></mover></math></span> <sub>eff</sub> should not exceed 212.44 <span><math><mrow><mi>GPa</mi><mo>∙</mo><msup><mrow><mi>m</mi></mrow><mrow><mn>1</mn><mo>/</mo><mn>2</mn></mrow></msup><mo>/</mo><mi>s</mi></mrow></math></span> and 226.63 <span><math><mrow><mi>GPa</mi><mo>∙</mo><msup><mrow><mi>m</mi></mrow><mrow><mn>1</mn><mo>/</mo><mn>2</mn></mrow></msup><mo>/</mo><mi>s</mi></mrow></math></span> for the specimens in the test, respectively. In addition, by inverting the maximum tangential stress (MTS) criterion, the dynamic tensile strength of pre-notched concrete SCB specimens has been determined. This innovative and effective method solves the previously unresolved challenge of calculating dynamic tensile strength in pre-notched SCB specimens. When the loading rates are 3.95 m/s and 4.79 m/s, the tensile strengths of the concrete are 11.63 MPa and 23.45 MPa respectively, and the strain rates are 10.78 s<sup>−1</sup> and 88.65 s<sup>−1</sup> respectively.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"140 ","pages":"Article 105210"},"PeriodicalIF":5.6,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144932687","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}
Jiquan Ma , Shunchuan Wu , Feng Dai , Haiyong Cheng , Jiaxin Wang , Yafan Zhang , Xiaolong Yang
{"title":"Study on crack propagation laws of two flaws with antarafacial strike lines in rock-like materials","authors":"Jiquan Ma , Shunchuan Wu , Feng Dai , Haiyong Cheng , Jiaxin Wang , Yafan Zhang , Xiaolong Yang","doi":"10.1016/j.tafmec.2025.105205","DOIUrl":"10.1016/j.tafmec.2025.105205","url":null,"abstract":"<div><div>The presence of flaws in natural rocks causes significant anisotropy in their strength and failure behavior. To investigate the impact of two flaws with antarafacial strike lines on the mechanical behavior of rocks, this study first conducted uniaxial compression tests using rock-like materials with prefabricated flaws at angles of 0°, 45°, and 90°. Subsequently, double-sided digital image correlation (DIC) and acoustic emission (AE) techniques were employed to analyze the failure characteristics of these specimens under the influence of two flaws at various angles. Finally, particle flow code was utilized to further interpret and validate the experimental results. According to the results, the weakening effects of the nine flaw angle combinations on uniaxial compressive strength and elastic modulus follow the order: two 0° flaws > one 0° flaw combined with one 5° flaw > two 45° flaws > one 0° or 45° flaw combined with one 90° flaw > two 90° flaws. For specimens with prefabricated 0° and 45° flaw combinations, the interaction between flaws is significant, exhibiting a pronounced dilatancy effect upon failure and generating transverse cracks and triangular or trapezoidal failure patterns. Additionally, more cracks are generated when the specimen initially fails, and multiple bursts of AE signals appear. The specimens are most prone to failure at the tips of the 0° flaws, at a certain distance away from these tips, and at the tips of the 45° flaws. Overall, these findings provide valuable insights and guidance for analyzing the failure characteristics of complex three-dimensional flawed rocks.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"141 ","pages":"Article 105205"},"PeriodicalIF":5.6,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145010882","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}
Shuxin Liu , Xiaofei Liu , Xiaoran Wang , Qiang Sun , Jinhua Wang , Jiaxin Shao , Joseph F. Labuz
{"title":"Acid-Induced fracture and pore structure evolution in basalt","authors":"Shuxin Liu , Xiaofei Liu , Xiaoran Wang , Qiang Sun , Jinhua Wang , Jiaxin Shao , Joseph F. Labuz","doi":"10.1016/j.tafmec.2025.105200","DOIUrl":"10.1016/j.tafmec.2025.105200","url":null,"abstract":"<div><div>Basalt has emerged as a promising candidate for in-situ mineral carbonation in CCUS applications. Developing fracture and pore networks in basalt formations is crucial for facilitating CO<sub>2</sub>-rock interactions by increasing the reactive surface area. This study investigates the mechanistic effects of acid-induced weakening on fracture propagation and pore structure evolution in basalt. Notched semi-circular bend (NSCB) tests were conducted under various pH conditions, combined with multi-scale characterization techniques including acoustic emission (AE) monitoring, nuclear magnetic resonance (NMR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The results show that with decreasing pH, the elastic modulus, peak load, and fracture toughness of basalt significantly decline, while the length of the fracture process zone (FPZ) increases. Meanwhile, the number of AE events and associated energy release intensify, suggesting earlier crack initiation and more rapid propagation. AE responses exhibit earlier onset, higher cumulative energy, and a marked increase in mid-to-low frequency, high-amplitude signals. Additionally, the proportion of tensile mode fractures increases with increasing acidity. NMR results indicate substantial increases in both micro- and macropore volumes following acid treatment. As acidity increases, the spatial and temporal fractal dimensions of AE events, along with the full-scale pore fractal dimension, generally decrease, reflecting enhanced internal connectivity of the pore network. Under stronger acidic conditions, these dimensions increase slightly, implying the development of more complex and dispersed microcracks and pores. The full-scale pore fractal dimension is positively correlated with the spatial and temporal fractal dimensions of AE events. From an engineering perspective, the integration of downhole logging with geophysical monitoring may offer a useful reference for real-time reservoir evaluation, contributing to improved injectivity and CO<sub>2</sub> sequestration efficiency in basalt formations.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"140 ","pages":"Article 105200"},"PeriodicalIF":5.6,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144988620","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":"Experimental study on the failure mechanism of sandstone containing en-echelon joints and anchoring control effect of NPR bolt","authors":"Yuxiang Feng , Ruixue Zhang , Zhigang Tao , Qinzheng Feng","doi":"10.1016/j.tafmec.2025.105207","DOIUrl":"10.1016/j.tafmec.2025.105207","url":null,"abstract":"<div><div>This study systematically investigates the failure mechanisms of en-echelon jointed rock with varying joint dip angles and the bolt anchoring control effects through uniaxial compression tests combined with acoustic emission monitoring and digital image correlation techniques. The results demonstrate that unanchored specimens exhibited through-going failure characteristics, with the severity of failure significantly increasing as the joint dip angle increases. When the joint dip angle ranges from 15° to 45°, the specimens exhibit tensile cracks through-going failure, with AE events being dispersed and strain concentration zones localized around the joints. In contrast, at higher dip angles (60°–75°), the specimens exhibit shear cracks through-going failure, with AE events concentrating during the failure stage and showing higher peak values. Bolt anchoring significantly improves the mechanical properties of en-echelon rock, effectively reducing the degree of failure and strain values. Furthermore, strain values in the anchored zone are lower than in the distal jointed regions. Meanwhile, it leads to more dispersed AE events with lower peak amplitudes during the failure stage. At higher joint dip angles, bolt anchoring transforms the specimen’s failure mode from through-going failure to block failure. Negative Poisson’s Ratio (NPR) bolt anchoring provides better anchoring effects and reduces the transition angle of failure modes. Bolt restraint is pronounced under low dip angle conditions, with axial force increasing sharply during the plastic stage. Under high dip angle conditions, axial force increases sharply only during the failure stage. These findings provide critical insights for optimizing support strategies in en-echelon jointed rock engineering.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"140 ","pages":"Article 105207"},"PeriodicalIF":5.6,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144925452","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}
Tianlong Ma , Qiaoling Zhang , Yongbin Ge , Wentao Ma
{"title":"A displacement-spatial co-adaptive strategy for the meshfree simulation of brittle phase-field fracture","authors":"Tianlong Ma , Qiaoling Zhang , Yongbin Ge , Wentao Ma","doi":"10.1016/j.tafmec.2025.105191","DOIUrl":"10.1016/j.tafmec.2025.105191","url":null,"abstract":"<div><div>While prior studies have typically explored displacement-adaptive (DA) or spatially adaptive (SA) strategies independently, few have achieved their integration within a unified phase-field framework. To our knowledge, this work presents the first integration of adaptive displacement step-size adjustment and damage-partitioned spatial refinement within the RPIM meshfree framework. For the DA component, we develop a variation-driven step-size adjustment algorithm, in which the next displacement increment is adaptively determined based on the maximum variations of the phase field and history strain energy between successive load steps, as well as the current step size. For the SA component, we embed our previously proposed damage-driven partitioned node refinement scheme [<span><span>1</span></span>], which automatically adjusts nodal density in low-, medium-, and high-damage zones without requiring prior knowledge of the crack path. By combining DA and SA with RPIM’s capabilities (including irregular geometry handling, accurate interpolation, and low mesh sensitivity), the unified DSA accelerates simulations through simultaneous reduction of displacement steps and spatial nodes, significantly improving computational efficiency over using DA or SA alone. Validation on 2D and 3D benchmarks confirms superior adaptivity, efficiency, and accuracy.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"140 ","pages":"Article 105191"},"PeriodicalIF":5.6,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144988619","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}