Theoretical and Applied Fracture Mechanics最新文献

{"title":"Experimental study of Rockburst in structurally controlled deep-buried roadways under static–dynamic coupling via true triaxial tests","authors":"Zhiqiang Qiao ,&nbsp;Kegang Li ,&nbsp;Mingliang Li ,&nbsp;Guojian Zeng ,&nbsp;Rui Yue ,&nbsp;Naeem Abbas","doi":"10.1016/j.tafmec.2025.105244","DOIUrl":"10.1016/j.tafmec.2025.105244","url":null,"abstract":"<div><div>This study explores the influence of different lateral pressure coefficients on rockbursts in deep-buried structural roadways under dynamic disturbance, using true triaxial experiments combined with acoustic emission and SEM analysis. The test results show that the lateral pressure coefficient significantly influences both the scale and location of roadway damage on the structural surface. The failure mode of the implied structural test samples is mainly the crack failure of the weak laminate, while the spalling of the edge of the structural plane is mainly the exposed structural surface. The initial damage of the implicit structural plane is the crack propagation of the weak layer, while the exposed structural plane begins with the separation of the free end of the structural plane. The structural planes significantly weaken specimen strength and accelerate overall failure. Based on fracture modes, two types of structural rockbursts are identified: surface-pressure-induced and buckling-induced. As the lateral pressure coefficient decreases, the cumulative AE count, energy release, and fractal dimension of rockburst debris exhibit a “V-shaped” trend initially weakening, then intensifying. Meanwhile, microcrack numbers decline and the proportion of shear cracks increases. Rockbursts in implied structures are more intense than in exposed ones. Although higher lateral pressure coefficients stabilize initial rock conditions, ultimately lead to stronger rockbursts. Both specimen types exhibit highly “instantaneous” and “sudden” failure, reflected by sharp peaks in acoustic emission activity.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"141 ","pages":"Article 105244"},"PeriodicalIF":5.6,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097140","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":"Analysis of mechanical properties and failure modes of single-fracture water-bearing sandstone under different dynamic disturbances","authors":"Mengjia Shi ,&nbsp;Dong Wang ,&nbsp;Yujing Jiang ,&nbsp;Xiaoming Sun ,&nbsp;Yong Zhang ,&nbsp;Chengyu Miao","doi":"10.1016/j.tafmec.2025.105242","DOIUrl":"10.1016/j.tafmec.2025.105242","url":null,"abstract":"<div><div>In the intricate geological milieu of deep mining areas, the interplay of water and fractures profoundly diminishes the stability of the surrounding rock, rendering it more susceptible to disturbances engendered by mining operations. This process triggers cumulative damage and initiates dynamic hazard failures, thereby compromising the stability of mine tunnels. The present study investigates the mechanical properties, energy dissipation, and evolution of failure modes of water-bearing single-fractured sandstone under dynamic disturbances of different amplitudes. The results indicate that: (1) Increased water content significantly reduces the compressive strength of sandstone, heightening its sensitivity to disturbances. (2) Across increasing disturbance amplitudes (1–5 MPa), sandstone exhibits significantly higher dissipation energy density and accelerated damage accumulation. While its failure mode transitions from tensile to mixed shear-tensile failure. These results provide fundamental insights into instability mechanisms and dynamic hazard control strategies for deep water-rich soft rock mines.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"141 ","pages":"Article 105242"},"PeriodicalIF":5.6,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145096722","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":"Correlation between the evolution of double-K fracture toughness and microstructural parameters in thermally treated granite","authors":"Jian Li ,&nbsp;Zhongping Guo ,&nbsp;Dechun Ai","doi":"10.1016/j.tafmec.2025.105240","DOIUrl":"10.1016/j.tafmec.2025.105240","url":null,"abstract":"<div><div>This study integrates Digital Image Correlation (DIC), Acoustic Emission (AE) in-situ monitoring, and quantitative microstructural analysis techniques to reveal the micromechanical control mechanisms of Double-K fracture toughness in heat-treated granite (25–800 °C). The observed evolution of the Fracture Process Zone (FPZ) by DIC, the broadband characteristics of AE time–frequency signals, and microstructural analysis collectively demonstrate that above 400 °C, grain boundary microcracks evolve from independent nucleation to networked interconnection, directly inducing a transition in granite fracture behavior from linear-elastic to nonlinear. By quantitatively characterizing microstructural parameters such as grain equivalent diameter, aspect ratio, and fractal dimension, it was found that the synergistic control of decreasing grain diameter, increasing aspect ratio, and rising fractal dimension governs the attenuation of Double-K toughness. Based on microstructural parameters including grain morphology and microcrack networks, an Artificial Neural Network (ANN) prediction model was constructed, achieving high-precision prediction of Double-K fracture toughness.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"141 ","pages":"Article 105240"},"PeriodicalIF":5.6,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145118881","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":"Dynamic tensile fracture of fissured sandstone: Fissure angle dependence","authors":"Jinwen Bai ,&nbsp;Shuquan Sun ,&nbsp;Xudong Shi ,&nbsp;Guorui Feng ,&nbsp;Jun Guo ,&nbsp;Shanyong Wang ,&nbsp;Xinyu Yang ,&nbsp;Kai Wang","doi":"10.1016/j.tafmec.2025.105241","DOIUrl":"10.1016/j.tafmec.2025.105241","url":null,"abstract":"<div><div>The dynamic tensile behavior of fissured rock masses critically influences the stability assessment of rock engineering structures under dynamic loading. In this study, dynamic Brazilian splitting tests were carried out on sandstone disc specimens with different prefabricated fissure angles using Split Hopkinson Pressure Bar (SHPB). Macroscopic damage characteristics—including dynamic tensile strength, energy dissipation patterns, and strain concentration—were quantitatively analyzed. Complementary PFC-FLAC coupled simulations revealed microscopic damage evolution through destructive processes and contact force distributions. Based on this, the effect of fissure angle on the damage mechanism was investigated. The results showed that dynamic peak load and reflected energy followed a concave trend with increasing fissure angle, while dissipated and transmitted energy percentages showed inverse correlations. The Strain concentration propagated along fissure direction and end-to-tip paths. Crack initiation consistently occurred at the incident bar contact point and nearest fissure tip. Damage severity followed parabolic evolution with fissure angles. The fissure angle not only had an effect on the stress extension path of the specimen during loading, but also controlled the stress redistribution of the specimen after loading. As the fissure angle increased, the crack changed from a direct tensile crack to a tensile shear crack.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"141 ","pages":"Article 105241"},"PeriodicalIF":5.6,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145096723","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 fatigue evaluation parameter for resistance spot welding with gap defects","authors":"Yulong Su ,&nbsp;Kai Song ,&nbsp;Yixin Chen ,&nbsp;Changye Liu ,&nbsp;Qihong Fang ,&nbsp;Hao Jin","doi":"10.1016/j.tafmec.2025.105238","DOIUrl":"10.1016/j.tafmec.2025.105238","url":null,"abstract":"<div><div>Resistance spot welding (RSW) is a prevalent method for connecting thin plates in automotive body structures, directly impacting structural safety. Variations such as sheet forming rebound, assembly deviation, and manufacturing errors often result in initial gaps (IGs) between sheets prior to welding. These gaps can exacerbate uneven plastic deformation, leading to warping deformations (i.e., gap defects) that significantly influence fatigue crack initiation and propagation rates, as well as the stiffness and fatigue resistance of the overall structure. Therefore, investigating fatigue evaluation parameters for RSW with gap defects is crucial for predicting service life accurately. Currently, there is a need to refine and optimize fatigue evaluation parameters for such defects. This study introduces a two-dimensional equivalent decomposition model for RSW with gap defects, deriving an analytical solution (AS) for the stress intensity factor (SIF) at critical locations based on linear elasticity theory. The finite element solution (FES) is obtained through finite element analysis. The results demonstrate a high level of consistency between the AS and FES, enhancing the SIF solution approach. Additionally, the analysis of fatigue evaluation parameters (FEP), a precise fatigue life prediction model with a correlation coefficient of 0.9019 is developed. This model offers theoretical support for practical engineering applications.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"141 ","pages":"Article 105238"},"PeriodicalIF":5.6,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145107226","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":"Thermal mechanical coupling fracture performance of granite under true Mode III loading: experimental realization and mechanism analysis via novel torsional testing","authors":"Zhi Wang ,&nbsp;Qingyu Yan ,&nbsp;Yingnan Gao ,&nbsp;Peng Li","doi":"10.1016/j.tafmec.2025.105239","DOIUrl":"10.1016/j.tafmec.2025.105239","url":null,"abstract":"<div><div>Accurately understanding the Mode III (tearing-mode) fracture behavior of rocks at elevated temperatures is essential for assessing the stability of engineered geostructures such as deep geothermal reservoirs. This study investigates the Mode III fracture characteristics of granite under thermo-mechanical coupling conditions, addressing a significant yet underexplored area in rock fracture mechanics relevant to deep geothermal applications. A novel torsion testing system was developed to conduct pure Mode III fracture experiments on square cross-section specimens with annular cracks at temperatures up to 800 °C. Finite element analysis confirmed a nearly pure shear stress state with negligible tensile components, validating the true Mode III crack propagation observed along the original notch plane. The results reveal a three-stage degradation of Mode III fracture toughness (<em>K_IIIC</em>) with increasing temperature: a gradual decline up to 200 °C, accelerated reduction between 200–400 °C, and stabilization above 600 °C, correlated sequentially with microcrack initiation, mineral dehydration, and quartz phase changes. At room temperature, the fracture toughness hierarchy <em>K_IIC</em> &gt; <em>K_IIIC</em> &gt; <em>K_IC</em> was quantified with ratios of <em>K_IIC</em> / <em>K_IC</em> = 2.33 and <em>K_IIIC</em> / <em>K_IC</em> = 1.81, respectively. Morphological transitions from brittle cleavage to plastic deformation features and thermally smoothed surfaces illustrate a brittle-to-ductile shift across temperatures. A normalized crack length threshold (2<em>a/W</em> ≥ 0.4) is established to ensure pure Mode III failure. Comparative validation using red sandstone confirms the reliability of the method, showing only 1.22 % deviation from existing results. This work establishes fundamental criteria for evaluating fracture behavior in deep geothermal environments under coupled thermal-shear loading.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"141 ","pages":"Article 105239"},"PeriodicalIF":5.6,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145047199","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 and statistical comparison of fracture and fatigue performance of notched geopolymer and conventional concrete beams","authors":"Sumit Singh Thakur,&nbsp;Zeeshan Abbas,&nbsp;Khushi Bansal,&nbsp;K.M. Pervaiz Fathima","doi":"10.1016/j.tafmec.2025.105211","DOIUrl":"10.1016/j.tafmec.2025.105211","url":null,"abstract":"<div><div>Sustainable alternatives to conventional concrete are gaining attention, and fly ash-based geopolymer concrete (GPC) is emerging as a promising material because of its potential for a lower carbon footprint and improved mechanical performance. However, existing studies lack detailed comparison of fracture and fatigue behavior of plain fly ash-based GPC with PCC at similar compressive strengths. This study investigates and compares the fracture and fatigue performance of fly ash-based plain GPC with ordinary Portland cement-based plain cement concrete (PCC) having the same compressive strength (M25) by conducting experiments on notched three-point bend specimens with three different initial notch lengths under static and cyclic loading. The results indicate that GPC demonstrates superior fracture and fatigue performance, withstanding more load cycles than PCC. The analysis reveals that the crack growth coefficient <span><math><mi>C</mi></math></span> of the size adjusted Paris’ law for GPC is significantly lower than that of PCC. However, both materials exhibit a similar crack growth exponent <span><math><mi>m</mi></math></span>. Microstructural analysis suggests that GPC’s enhanced fracture and fatigue performance is linked to its spheroidal globular type three dimensional microstructure and its elemental composition. Statistical analysis further confirms the superior performance of GPC over PCC at different stages of crack growth, with its variability best captured by log-uniform distribution in monotonic loading and Beta distribution in cyclic loading. Furthermore, the application of a predictive boundary effect method (BEM) confirmed the existence of a size effect in GPC. The findings of this study suggest that GPC could serve as a more durable and sustainable material for transit infrastructure such as roads, bridges, and rail sleepers subjected to cyclic loads.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"141 ","pages":"Article 105211"},"PeriodicalIF":5.6,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145061231","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":"Study on mechanical properties and failure mechanism of single-fractured granite under impact load","authors":"Hui Guo ,&nbsp;Weizhou Chen ,&nbsp;Ying Li ,&nbsp;Jun Wang ,&nbsp;Siting Huang ,&nbsp;Cheng Tao ,&nbsp;Yu Chen","doi":"10.1016/j.tafmec.2025.105236","DOIUrl":"10.1016/j.tafmec.2025.105236","url":null,"abstract":"<div><div>Fractured granite is a predominant geological medium in underground mining, tunnel excavation, and rock mass reinforcement. Its mechanical behavior under complex loading conditions directly controls engineering stability and long-term operational safety. However, systematic research on single-fractured granite remains insufficient, particularly regarding the influence of geometric characteristics (e.g., fracture inclination angle, length, and width) on its mechanical properties, failure mechanisms, and energy dissipation. This knowledge gap impedes accurate stability assessment and risk mitigation in practical engineering applications. This research employs a microcomputer-controlled electro-hydraulic servo universal testing machine and a split Hopkinson pressure bar to conduct quasi-static and dynamic compression tests on single-fracture granite of three different strengths. Simultaneously, LS-DYNA is used to establish numerical models of single-fracture granite with different fracture geometries to deeply investigate the specific impacts of fracture angle, length, and width on the mechanical properties and crack propagation characteristics of single-fracture granite through numerical simulation. The results show that intact granite under stress waves forms axial shear-tensile cracks, while single-fractured granite generates wing-shaped cracks from the prefabricated fracture tip. Lower strength in single- fractured granite leads to higher energy efficiency. Crack initiation shifts clockwise along the fracture edge with increasing inclination, involving oblique shear cracks along the fracture and diagonal shear cracks from the vertices. For fracture lengths &lt; 20 mm, stress concentration is balanced. For fracture lengths ≥ 20 mm, stress focuses at the upper end, causing upward shear cracks. Wider fractures reduce shear cracks along the prefabricated fracture but intensify damage from vertex-initiated shear cracks. The critical fracture parameters (20 mm length, 45° inclination) and energy dissipation laws derived from this study provide a quantitative basis for stability assessment of fractured rock masses, optimization of support schemes, and early warning of rock burst risks in underground engineering.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"141 ","pages":"Article 105236"},"PeriodicalIF":5.6,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145047198","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":"Crack path under non-proportional fatigue loading — Evaluating tests with existing crack growth direction criteria","authors":"Sjoerd T. Hengeveld ,&nbsp;Davide Leonetti ,&nbsp;H.H. (Bert) Snijder ,&nbsp;Johan Maljaars","doi":"10.1016/j.tafmec.2025.105069","DOIUrl":"10.1016/j.tafmec.2025.105069","url":null,"abstract":"<div><div>Proper descriptions of the fatigue crack growth rate and direction are crucial for determining the residual fatigue life of metallic structures. In non-proportional multi-axial loading, the prediction of the fatigue crack growth direction is not trivial. This study evaluates the effect of different state-of-the-art crack growth direction criteria on the predicted crack paths by comparing the results with experiments with non-proportional load done by others. The results are compared in terms of predicted angles at different experimental crack lengths and cumulative predicted crack path. Based on this study, it is concluded that none of the studied criteria based on linear elastic fracture mechanics is able to accurately predict the crack growth direction in non-proportional loading for the general case. The mismatch of some cases studied is so large that these criteria cannot be used in crack growth path prediction for an arbitrary, non-proportional load case.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"141 ","pages":"Article 105069"},"PeriodicalIF":5.6,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145159183","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":"Mechanical behaviors and fracture characteristics of heat-treated sandstone with pre-existing flaw under uniaxial compression: A study on the failure behavior of flawed building sandstone after fire","authors":"Weijing Xiao ,&nbsp;Kun Liu ,&nbsp;Dongming Zhang ,&nbsp;Haosen Guo ,&nbsp;Shujian Li ,&nbsp;Hongpeng Wan","doi":"10.1016/j.tafmec.2025.105231","DOIUrl":"10.1016/j.tafmec.2025.105231","url":null,"abstract":"<div><div>In civil engineering, building sandstone often develops defects due to weathering and crustal movement.<!--> <!-->Investigating the failure mechanisms of such defective rocks under elevated temperatures is therefore essential for postfire restoration and stability analysis of buildings. In this paper, uniaxial compression experiments are conducted on the flawed sandstone exposed to temperatures ranging from 25 °C to 1000 °C. The stress–strain curves, acoustic emission (AE) signals and macroscopic fracture images of rock are obtained. The rock mechanical properties and fracture characteristics are analyzed. The results show that: (1) the strength of the sandstone is the highest at 200 °C, and the peak strength decreases with temperature rise after 200 °C, and the energy dissipation becomes more significant. (2) the failure starts from the wing crack at the flaw tips, and then gradually cross through to form a macroscopic fracture surface. The complexity of rock fracture cracks increases exposed to temperatures more than 400 °C, and the fluctuation of AE correlation dimension reflects the nonlinear evolution process of rock internal damage. (3) When the temperature is lower than 400 °C, the proportion of shear cracks exceeds that of tension cracks only when the stress level exceeds 80 %. When the temperature reaches 800 °C, the proportion of shear cracks always exceeds that of tension cracks, and the progressive failure is particularly obvious, which is related to rock thermal fracture and the loose rock particles after high temperatures. The research results provide reference for post-disaster restoration and stability analysis of rock buildings after fire.</div></div>","PeriodicalId":22879,"journal":{"name":"Theoretical and Applied Fracture Mechanics","volume":"141 ","pages":"Article 105231"},"PeriodicalIF":5.6,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145096724","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}