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Paper‐based friction materials with phenolic resin as the matrix are prone to thermal damage under harsh working conditions easily leading to materials failure. To satisfy the requirements of high speed and heavy load service situations, paper‐based friction materials with different polyimide resin content were prepared by wet forming technology to reveal the effect of polyimide resin on the properties of composites. And a paper‐based composite with phenolic resin was used for comparison. Results show that compared with the phenolic composite, tensile strength, and shear strength of the polyimide composite were increased by 50.5% and 36.4%, respectively. Due to the strong hydrogen bond in the imide ring of polyimide, the temperature of the polyimide composite at 2% weight loss was 292.7°C, which was 106.3°C higher than that of the phenolic composite. Moreover, the wear rate was reduced by 30.3% because the friction transfer film was produced during friction. To sum up, polyimide resin has the potential to replace phenolic resin under the condition of high speed and heavy load. Besides, the composite with polyimide resin content of 40.0 wt% demonstrated the best wear resistance and considerable strength attributed to the best interface combination. This research lays a theoretical foundation for the application of polyimide resin to paper‐based friction materials. [ABSTRACT FROM AUTHOR]

Fracture mechanics are utilized to successfully predict the allowable bend radii achieved through experimentation for ion‐exchanged glass having thicknesses of 25 to 125 microns. The origin of the non‐monotonic relationship between puncture resistance and glass thickness is also described. [ABSTRACT FROM AUTHOR]

A better physical understanding of mesoscale and microscale mechanisms behind deformation and failure of paperboard material is important to optimize industrial packaging converting processes and decrease waste. In this study, these mechanisms were investigated using synchrotron X‐ray tomography during in situ continuous uniaxial tensile loading. High spatial and temporal data resolution enabled quantification of rapid changes in the material occurring before, during and after material failure. The evolution of 3D strain fields, fibre orientations and sample thickness showed that deformation and failure mechanisms differ significantly between samples tested in machine direction (MD), cross direction (CD) and 45° from the loading direction. In 45° and CD, gradual failure processes could be followed across several load steps. Immediately after failure, the in‐plane fracture region was significantly larger in both 45° and CD compared to MD. Both fracture characteristics and strain field distributions differed between the three material directions. Significant fibre reorientation was an active deformation mechanism in 45° already from the beginning of the loading, also present in CD after peak load but absent in MD. The MD‐dependent mechanisms interpreted and quantified at the scale of the fibre network in this study can help guide model development and likely have wider applicability to other paper‐based materials. [ABSTRACT FROM AUTHOR]

Since the first paper on the fatigue of metallic materials by J. Albert in 1837, tremendous numbers of papers have been published in various journals by many researchers all over the world. Based on such a long history, several papers on the very high cycle fatigue (VHCF) in the life‐time longer than 107 cycles had appeared in some journals during the period of 1980's. One characteristic finding in these works is the fact that the metallic material can fail even at the stress level lower than the conventional fatigue limit. This fact means that the conventional fatigue design of mechanical structures cannot give the safety of the practical products in the very high cycle regime. Due to this fact, fatigue properties of structural materials in very long life regime has become an important subject; and a lot of studies have been carried out, and many important results have been accumulated until now. Typical aspects on VHCF property are summarized as follows: (1) the fatigue crack tends to occur around the interior inclusion, (2) fine granular area (FGA) is formed around such an inclusion, and (3) duplex S–N characteristics appear in the VHCF regime. In this paper, a brief historical review together with the future prospect on the very high cycle fatigue of metallic materials is attempted for the sake of reference to facilitate the research in this area. Highlights: Historical review and future prospect for researches on metal fatigue.Progress of researches on very high cycle fatigue of metallic materials.Review of interior crack initiation and growth mechanisms around inclusion.Quantitative formulation of interior crack growth around inclusion. [ABSTRACT FROM AUTHOR]

The in‐plane static fracture of a fabric reinforced all‐poly(propylene) (all‐PP, Curv®) composite was studied at ambient temperature using the concept of the linear elastic fracture mechanics. The apparent fracture toughness was determined on single‐edge notched tensile specimens (SEN‐T) considering the maximum load. The related values did not differ much from those determined by the resistance curve (KR) method. The crack growth, requested to construct the KR curves, was traced by the movement in the center of gravity of the cumulative amplitude of the located acoustic emission (AE) events. The quality of consolidation of the all‐PP composite was reflected by the force‐displacement curve (appearance of pop‐in), course of the cumulative AE events during loading, extension and change of the estimated damage zone during fracture. The failure behavior was studied also by fractography and is discussed. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In a recent paper in Structural Concrete, the authors Dönmez and Bažant explain that the theoretical background of the Model Code 2010 equations for one way and punching shear are not sufficiently grounded in theory and should instead use an energy‐based size effect law in their formulation to match behavior. To support this claim, finite element simulations were presented. In this paper the basic assumption that an energy‐based method must govern the shear failure of beams without stirrups is questioned. These questions are shown to be based on the hardening behavior of aggregate interlock tests and the inability for slip strains to localize during shear failure. In addition to these theoretical arguments finite element analyses were conducted with a constitutive model that is energy‐based but that also does an appropriate job at modeling aggregate interlock, an aspect that appears to be lacking in the analyses of Dönmez and Bažant. These new results are shown to better model the test results and confirm that aggregate interlock is important in explaining shear strength and therefore the size effect in shear for slender members. As such any concerns about the safety of the Model Code shear equations appear unwarranted. [ABSTRACT FROM AUTHOR]

Proof testing is used to remove weak ceramic components from a manufactured batch in turn truncating the lower end of the strength‐failure probability distribution. With proof testing, components are subjected to stresses comparable to those observed during service load histories resulting in the remaining ones having assured minimum reliabilities. The degree to which the reliability of the remaining parts is assured depends on the proof test protocol, which includes multiple variables such as stress level, realistic sampling of flaws, complex geometries, multiaxial stresses, transient loading histories, time‐dependent damage due to slow crack growth and/or fatigue, and change in material behavior due to temperature and/or environmental conditions. This paper advances the early work done on proof test theory, which was limited to simple stress states, to include general stress and material states. The theory introduced in this paper takes into account practical conditions often encountered in industrial applications. This advanced proof test theory was coded into the CARES/Life code (Ceramics Analysis and Reliability Evaluation of Structures/Life). Examples are provided to demonstrate the theory. [ABSTRACT FROM AUTHOR]

The article discusses a study which was carried out to investigate the local and effective fracture behaviour of polycrystalline silicon for microelectromechanical systems (MEMS). The apparent mode I critical stress intensity factor was determined from MEMS-scale tension specimens. The distribution of values was attributed to local cleavage anisotropy and to enhanced grain boundary toughening.

This paper starts with an overview of the application of the three guidelines (GL) of the German Research Association of Mechanical Engineers (FKM). Each of these provides algorithms for calculating fatigue lives of components under constant or variable amplitude loading, however, with underlying different failure criteria, that is, technical crack initiation life (GL‐nonlinear), fatigue crack growth life (GL‐fracture mechanics), and total fracture life (GL‐linear). Since the GL‐linear only considers linear‐elastic material behavior in the fracture fatigue life calculation, the guideline is not capable for the LCF and is not able to take sequence effects into account. For a better approximation of fracture fatigue lives, the elastic–plastic material behavior has to be taken into account. This paper introduces the U‐Concept which has been evaluated from a large structural durability database from the literature with more than 1,500 experiments for constant and more than 700 experiments for variable amplitude loading. The U‐Concept is a small add‐on to the local strain approach (LSA) which is the backbone of the GL‐nonlinear. It enables (1) to directly calculate the fatigue life to total fracture based on elastic–plastic material behavior according to the LSA or (2) to estimate the remaining fatigue life from crack initiation to fracture without a crack growth simulation. Furthermore, the U‐Concept needs no experimental determined crack growth parameters, the only necessary material parameter is the ultimate tensile strength Rm. The U‐Concept is therefore easy applicable for industrial users and increases the accuracy of the approximated fatigue lives by considering the elastic–plastic material behavior. [ABSTRACT FROM AUTHOR]

The material network in the chemical process has the characteristics of a complex network. Once the fault occurs, it will spread and lead to cascading failures, causing the chemical production process to not proceed normally. Previous studies of cascading failures have been limited by the size and characteristics of the network, which prevented the definition of the fault propagation capacity of the edge based on the actual situation. Studies on the effects of network topology and certain risk factors on the amount of fault propagation still need to be completed. Because of the above shortcomings, this study constructs a chemical material network cascading failure invulnerability analysis model that considers the failure propagation ability. Through the study of the chemical material network topology structure and the analysis of various flammable and explosive chemicals, the paper defines the fault propagation coefficient, which affects the load propagation quantity on the connecting edge. Then, based on the load‐capacity nonlinear cascading failure model, the chemical material network's invulnerability was analyzed by adjusting the model parameters. The effectiveness of the model is verified through case analysis. Compared to the existing model, the model in this paper effectively improves the invulnerability of the material network and can reduce the phenomenon of large‐scale failure of the material network due to the failure propagation capability is not considered. [ABSTRACT FROM AUTHOR]

MIL‐STD 1530D requires that the certification of an aircraft part employ analytical tools that are capable of modeling crack growth. It is further stated that the durability and damage tolerance (DADT) analyses should be based on linear elastic fracture mechanics (LEFM) and follow a building block approach. This paper illustrates the durability analysis required to certify an additively manufactured part by using the examples of durability tests performed on two wire arc additively manufactured (WAAM) 18Ni 250 Maraging steel specimens. Highlights: Examines the growth cracks in WAAM 18Ni 250 maraging steel specimens with rough surfaces.Reveals that cracking in specimens with rough surfaces is characterized by a single equation.Illustrates the Hartman–Schijve equation for assessing specimens with rough surfaces. [ABSTRACT FROM AUTHOR]

A computational framework of anisotropic phase field model is used to investigate the effects of effective critical energy release rate, interface property, and hole shape on the failure of composite material in this paper. This model is implemented in ABAQUS using a user‐defined element (UEL). First of all, the model is validated through a benchmark model. Second, the effective critical energy release rate is introduced, which can improve the accuracy of the simulation result. Then, the influence of strong and weak interfaces on the failure of composite material is studied. It can be found that the interface properties can change the evolution mode of crack and the final load–displacement response. Finally, the effect of hole shapes on the failure of the composite material is also explored, which shows that the bearing capacity of model can be improved by changing the shape of the hole. [ABSTRACT FROM AUTHOR]

Metal additive manufacturing technologies provide new opportunities for manufacturing complex components. However, the limited data on fracture behavior are delaying adoption in safe‐critical applications. This paper aims to evaluate the effect of orientation and the intra‐build design parameters on EBM Ti6Al4V fracture toughness using a design of experiments. Three builds comprised of over 150 compact tension samples were printed representative of the EBM build chamber, followed by microstructural characterization, X‐ray microcomputed tomography, and fracture toughness testing per ASTM E399. The average fracture toughness was 65 MPa√m, with anisotropy as the largest source of variation due to crack growth behavior with respect to the build direction. Microstructure coarsening was observed with increase in height, resulting in an increase in fracture toughness, irrespective of sample geometry or orientation. Build orientation and sample location influenced the microstructure and fracture toughness and should be considered when adopting EBM components in load‐bearing applications. [ABSTRACT FROM AUTHOR]

This paper reports the damage mechanism of 30Cr1Mo1V rotor steel during thermal fatigue at 540°C. Detailed information on macro‐failure characteristics and micro‐failure mechanisms was revealed here. The results showed that both intragranular micro‐defects and intergranular micro‐crackings were formed during the fatigue process. The formation of intragranular micro‐defects was related to the dislocation tangle inside the ferrite sub‐grains, while the formation of intergranular micro‐cracking could be related to the weakening of atomic cohesion at the matrix/cementite interface. Eventually, the transgranular crackings occurred in the 30Cr1Mo1V steel. The morphology of these crackings presented an edge‐shaped discontinuity, which may propagate perpendicularly to the loading direction and cause the material to fracture. [ABSTRACT FROM AUTHOR]

In this paper, blends of ABS‐TPU with two different weight percentages of TPU were prepared using fused deposition modeling technology. The effect of adding TPU on the fracture toughness of ABS and mechanical properties was comprehensively studied. Tensile, compression, fracture toughness, and shear tests were conducted on the 3D‐printed samples. Thermal and microstructural analyses were performed using dynamic mechanical thermal analysis (DMTA), and scanning electron microscope (SEM). The DMTA results showed that adding TPU decreased the storage modulus and the glass transition temperature of ABS, as well as its peak intensity. The mechanical test results showed that adding TPU decreased the strength but increased the formability and elongation of the samples. Fracture tests showed that the addition of TPU decreased the maximum force needed for a crack to initiate. The force required for crack initiation decreased from 568.4 N for neat ABS to 335.3 N for ABS80 and 123.2 N for ABS60. The ABS60 blend exhibited the highest strength against crack growth, indicating that TPU can change the behavior of ABS from brittle to ductile. Shear test results and SEM images also showed good adhesion strength between the printed samples for all three specimens, indicating their good printability. Adding TPU resulted in a reduction in the size and number of voids and holes between the printed layers. Highlights: Melt mixing, filament preparation, and 3D printing of ABS‐TPU blends.Investigation of mechanical properties, microstructure, and fracture toughness.Improved resistance to crack growth and elongation by adding TPU to ABS.Improving printability and reducing microholes in blends compared with ABS.Achieving a wide range of mechanical properties for various applications. [ABSTRACT FROM AUTHOR]

Crack assessment has remained one of the high‐priority research topics for structural health monitoring. However, the current research mainly focuses on the crack assessment at some point, but pays relatively less attention to the long‐term development of cracks, which is important for structure health monitoring. In this paper, a new method based on dual‐convolutional neural network (CNN) (well over 94% accuracy), digital image processing technology and shape context is proposed, which achieves a fully automated process composed of crack detection, crack measurement, and quantitative crack growth monitoring. In crack growth monitoring, an algorithm to label each crack is put forward for the first time, which is able to reflect the sequential order of the occurrence of cracks. Therefore, each skeleton point of cracks will be assigned an ID which contains information about its identity and width in order to monitor cracks at both a global and local level. Experimental studies of a concrete member with complex cracks are utilized for the illustration and validation of the proposed methodology. [ABSTRACT FROM AUTHOR]

This paper describes finite element simulations of the structural deformation and material fracture behaviour of high‐strength steel RHS K gap truss joints. The fundamental scope was to examine whether the joint strength predictions based on the behaviour of lower strength and more ductile steel with a yield stress of 355 MPa or less would hold good for higher strength 450 MPa steel with a lower ductility. The FEA reliability analysis indicates that for failure modes associated with local buckling, yielding and deformation (chord side wall failure, chord face plastification and brace failures due to reduced effective width), the existing approach could, with modifications, be extended to cover higher strength tubes, but for failure modes associated with fracture or ductility or modes liable to brittle failure (tearing in the tension brace and chord punching shear), a strength reduction modifying factor was required. The finite element simulations incorporated a damage mechanics approach to calibrate experimental results in both the fracture and deformation modes of failure. The paper proposes a new formulation for strength and incorporates reduced ductility in high‐grade steel with a modifier function that is not based on yield stress, instead recognizes the reduced ultimate strains, damage parameter for fracture and ultimate stress of the material. [ABSTRACT FROM AUTHOR]

The present paper deals with the J‐A concept in two‐parameter elastic–plastic approaches of fracture mechanics. The cumulative damage rule in a solid is employed to construct the quantitative elastic–plastic J‐A fracture criterion. As a result, the constraint corrected elastic–plastic fracture toughness JmatC as a function of the crack‐tip constraint parameter A, the yield stress, the strain hardening exponent and the failure stress has been proposed. The significant effect of the strain hardening exponent on the normalized constraint corrected fracture toughness is observed. The value of the normalized constraint corrected fracture toughness decreases with the increase of the applied failure stress and the decrease of the crack aspect ratio to a certain values, and then it stabilizes. Highlights: The cumulative damage rule in a solid and the J‐A concept are employed.Quantitative two‐parameter J‐A fracture criterion is proposed.The constraint corrected fracture toughness is described as a function of crack‐tip constraint.The effect of the constraint parameter A is analyzed for some standard specimens. [ABSTRACT FROM AUTHOR]

In this paper, comprehensive progressive damage analyses are performed to evaluate the effects of patch sizes and layups on restarting crack growth of single‐side repaired aluminum panels with central inclined cracks under high cycle fatigue loading. Complicated nonlinear damage behavior of adhesive bonding, composite patch, mixed‐mode cracks, and fatigue loadings require precise numerical tools to consider and analyze the coupling effects of various damages on fatigue life of such complex component. In progressive damage analysis, high cycle fatigue cohesive zone modeling is used for debonding of patch, and high cycle fatigue continuum damage model used for composite patches. Practical composite patch layups and sizes are selected in huge number of models, and the restarting crack growth life is predicted. The obtained results show the possibility of increasing the restarting crack growth life using an appropriate composite patch layup and geometry dimensions. Highlights: Restarting crack growth of single‐side repaired panels fatigue loadingComprehensive progressive damage analysesEffects of composite patch size and layup on restarting crack growthCrack growth retardation using appropriate composite patch [ABSTRACT FROM AUTHOR]

This paper investigates the fracture behavior of high‐performance grouting materials in the grouted connection section of marine structures, where they are subjected to complex stress states. This study utilizes a combination of experimental and numerical simulation methods to establish a reliable numerical simulation technique for the fracture process of high‐performance grouting materials. The mixed mode fracture behavior is analyzed using six different types of specimens, and the strain contour is analyzed using the Digital Image Correlation technique. An extended peridynamics model is proposed for the numerical simulation, which adopts a fracture criterion based on strain energy density. The accuracy of the model is verified qualitatively and quantitatively, and the simulation results are consistent with the experiments. Overall, this study provides insights into the fracture behavior of high‐performance grouting materials in complex stress states and presents a reliable numerical simulation technique for the fracture process. Highlights: Different fracture criteria were used to analyze the four points bending test results.Digital Image Correlation technique was adopted to predict the crack initiation position and failure mode.The failure mode, failure angle, and fracture toughness of material were discussed.An extended peridynamics model is established for failure analysis of grouted material. [ABSTRACT FROM AUTHOR]

Advanced fatigue assessment methods, e.g. the Two‐Stage‐Model, are needed for the design of complex constructions or to accurately evaluate the remaining fatigue life of existing structures. The applicability of the Two‐Stage‐Model, including strain‐life approach and linear elastic fracture mechanics, was experimentally validated for uniaxial stress states only. However, typical construction details of steel and composite structures often exhibit a multiaxial non‐proportional stress state, which leads to variable principal stress values and directions. Comprehensive extensions of the Two‐Stage‐Model from uniaxial to multiaxial stress states are missing so far. This paper shows a study on advanced approaches that incorporate multiaxial stress states for both the crack initiation stage and the crack propagation stage, and their application in the Two‐Stage‐Model. For crack initiation, several approaches for the strain‐life approach, including multiaxial non‐proportional hardening and damage assessment based on critical planes are evaluated with respect to an application on the strain‐life approach. For the extension of the crack propagation stage, a computational procedure using XFEM and mixed‐mode approaches is presented. [ABSTRACT FROM AUTHOR]

This paper develops a mesoscopic numerical method for evaluating the fracture energy of concrete. In this method, concrete is modeled as a three‐phase composite material, composed of mortar, coarse aggregate, and the interface between them. The actual mixed‐mode I–II crack growth path in mode I fracture tests is traced by applying crack propagation criteria. After verifying the numerical method by a series of three‐point bending tests, the effects of aggregate location, aggregate size, and crack propagation path on the fracture energy of concrete are evaluated. It is found that for the fracture mode of crack bypassing aggregates, the actual fracture energy of concrete is significantly affected by the aggregate location but independent of the aggregate size and the crack propagation path. Highlights: A mesoscopic numerical method is proposed for the fracture energy of concrete.The actual mixed‐mode I–II crack growth path is traced by applying crack growth criteria.The actual fracture energy of concrete is significantly affected by aggregate location.The actual fracture energy of concrete is independent of crack growth path. [ABSTRACT FROM AUTHOR]

The papers summarize recent findings in numerical and theoretical models aimed to assess the fracture and fatigue behavior of structural components as well as new interesting set of data combined with new experimental techniques. Thus, this VSI embraces different works aimed to understand the material behavior using advanced approaches, disruptive fracture mechanics concepts, and advanced experimental techniques for fatigue crack behavior assessment. Also, the effect of different manufacturing processes on the fatigue and crack propagation behavior is addressed.3,4 Other works are focused on fracture mechanics formulations. [Extracted from the article]

In the past decade, polymer‐based glass fiber‐reinforced laminate composites have gained significant popularity in various mass transit applications, including marine, aircraft, and automotive industries. However, it is crucial to consider the degradation and potential failure of these materials, especially in mass transit networks. To address this concern, fractographic analysis has emerged as a valuable approach for investigating fracture surfaces, extracting vital information, and facilitating the development of new materials. Furthermore, it sheds light on the underlying physical mechanisms that contribute to composite failure. This paper primarily focuses on examining flaws, failure modes, and performing fractography analysis on fiber‐reinforced polymer (FRP) laminate composites subjected to various loading conditions such as tension, compression, flexure, impact, shear, and fracture. Fractography, as an indispensable method, plays a pivotal role in the comprehensive development of composite structures and has become a reliable tool for composite engineers. The outcomes of this study are expected to serve as a foundation for identifying areas that require further investigation in terms of fracture analysis and failure modes specific to FRP composite materials, particularly those used in marine applications. Highlights: Introduction to FRP laminate composites in marine structures.Concise analysis of failure modes in FRP laminate composites.SEM fractography review of FRP laminate composites under varied loading conditions.Comprehensive study on tensile, flexural, impact, compression, shear, and fracture toughness failure modes.Summarization of identified defects in FRP composites. [ABSTRACT FROM AUTHOR]

The composite interlamination is the key part of load transfer and plays a decisive role in the overall mechanical performance of composite structures. The interlaminar property is predominantly influenced by the matrix resin which is easily affected by the hygrothermal environment. This paper delved into the effect of hygrothermal aging duration on the interlayer debonding behavior of unidirectional (UD) laminates. The pre‐cracked specimens were treated by hygrothermal aging with a period of 0, 15, 30, 60, 90, and 120 days. The double cantilever beam (DCB) tests were employed to evaluate the interlaminar property. The effect of hygrothermal aging on load–displacement responses, R‐curves, crack growth speed, and fracture surface topography was analyzed. The results revealed that the load‐bearing capacity of aged specimens presented a reduction of 18.6%–29.0% compared with unaged ones. The interlaminar fracture toughness of specimens subjected to 15 days of treatment decreased significantly compared with that of unaged specimens due to the increase of water absorption caused by hygrothermal aging. With the increase in hygrothermal aging time, the interlaminar fracture toughness peaked at 60 days because of the post‐curing effect, followed by a declining trend influenced by the dominant hygrothermal aging effect. The fiber bridging of aged samples was increasingly obvious, became the most prominent at 60 days, and then gradually reduced. The fiber bridging diminished the crack propagation speed, hindered interlaminar debonding, and contributed to the interlaminar toughening. Highlights: The samples underwent hygrothermal aging for 0, 15, 30, 60, 90, and 120 days.Load ability of aged samples was at least 18.6% lower than that of unaged ones.R‐curves rose before the crack length of 79 mm and then tended to stabilize.Fracture toughness first decreased, then increased and reduced with aging time.Fiber bridging could hinder crack growth and improve the interlayer property. [ABSTRACT FROM AUTHOR]

This paper presents a novel high‐resolution direct analysis of mating AA7050‐T7451 fracture surfaces at crack lengths from 0.1 to 1.3 mm (Kmax of 4.51 to 16.39 MPa√m) for the purpose of analyzing the fatigue growth mechanisms. The various fractographic features observed at these crack lengths were then compared to the known accelerative effects of an applied loading sequence that contained underloads at regular intervals. A correlation was found between some of the observed features and the local fatigue crack growth rate. This study provides new insight into the prominent mechanisms that dictate crack growth rate and ultimately should assist with developing crack growth prediction methods that more accurately represent the physics of the fatigue crack growth mechanisms. Highlights: Mating fatigue surfaces are compared at high resolution in AA7050‐T7451.Striation features are shown to significantly differ on mating surfaces.Fissuring from underloads is found to occur at all investigated crack lengths.This fissuring may be mechanistically linked to underload acceleration effects. [ABSTRACT FROM AUTHOR]

In degradation modeling, stochastic processes often do not meet the classical properties necessary for traditional goodness‐of‐fit tests. This paper presents an initial investigation into employing the ACH depth function and its potential in degradation model selection. We commence by presenting various stochastic processes as degradation models and their selection criteria. Subsequently, we delve into the ACH depth function, highlighting its potential in this context. Through simulated data, we assess the application of this functional depth measure for model selection. The methodology's validity is further reinforced by its application to real‐world data, underscoring its effectiveness. [ABSTRACT FROM AUTHOR]

This paper presents an extensive experimental investigation on fatigue properties of carbon‐black filled isoprene rubber under complex loadings. A basic life prediction model taking strain energy density as fatigue parameter is first proposed based on fatigue crack growth tests and uniaxial tension fatigue tests under relaxing loads at room temperature. A database of fatigue life including relaxing and non‐relaxing is established through a great number of fatigue tests under five temperatures. Based on the database, two empirical parameters, that is, temperature factor (NRT/NHT) and life reinforcement factor (Re), are introduced to quantitatively characterize the coupling effects of high temperature and non‐relaxing loads on fatigue life. The fatigue mechanisms under different conditions are compared via wide‐angle x‐ray diffraction tests and postmortem analysis. It reveals that the weakening of life reinforcement at high temperatures is closely related to the strain induced crystallization behavior of rubber. [ABSTRACT FROM AUTHOR]

2.5D woven structures are of interest in new thermal protection systems for their excellent interlayer properties and structural stability. In this paper, dense (CDP) and lightweight (CLP) carbon/phenolic 2.5D woven composites were prepared. Quasi‐static tensile experiments were performed on the specimens before ablation (TCDP‐0, TCLP‐0) and after ablation for 30 s (TCDP‐30, TCLP‐30). A quarter macro–meso hybrid model that takes into account the degradation of material properties after ablation and ablative crack pores was innovatively proposed. The predicted tensile elastic modulus is within 9% error from the experimental results. The results show that TCDP‐30 and TCLP‐30 have rapid damage expansion and lethal injury at smaller displacements than the pre‐ablation specimens. The displacement of the maximum load point of TCDP‐30 is 38.7% lower than that of TCLP‐30. The forms of damage in TCDP‐30 are dominated by matrix fragmentation and matrix cracks. The damage forms of TCLP‐30 are dominated by debonding and delamination. Highlights: Micro‐CT was used to collect matrix fabrication defects and ablative crack pores defect.A quarter macro–meso hybrid model that takes into account the degradation of material properties after ablation and ablative crack pore was innovatively proposed.The tensile failure mechanism of the material after ablation was revealed by the combination of experiment and numerical method. [ABSTRACT FROM AUTHOR]

Thermomechanical fatigue (TMF) crack growth of Alloy 718 when the cycle includes long high‐temperature tensile dwells is often accelerated because sustained‐load crack growth occurs during the dwells and a temperature affected zone (TAZ) develops ahead of a crack tip that reduces fatigue crack growth resistance upon application of a cycle after the long dwell. This paper presents new TMF and sustained‐load tests that aim to study and characterize the TAZ development and growth ahead of semi‐elliptical and single‐edge cracks. The influence of constraint on crack growth is assessed. This investigation focuses on a coarse‐grained (CG) Alloy 718 at 650°C. By comparing the crack growth behavior between a fine‐grained and CG microstructure after a long tensile dwell, a modification of the TAZ growth prediction model that includes the influence of grain size is proposed. Using this improved model for TAZ growth and acceleration, the TMF crack growth prediction of surface cracks is improved. Highlights: Temperature affected zone (TAZ) develops during tensile dwells in Alloy 718.The extent of TAZ is reduced when grains are larger.The extent of TAZ is also dependent on the constraint near the crack tip.A new grain size dependent TAZ growth model improves TMF predictions. [ABSTRACT FROM AUTHOR]

The numerical approach is a vital means for evaluating the stability of flawed rocks. In this paper, the extended non‐ordinary state‐based peridynamics (NOSB‐PD) theory is employed to simulate the fracture process of rocks containing two pre‐existing flaws. Two stress criteria, including the maximum tensile stress criterion and the Mohr–Coulomb criterion, are implemented into the NOSB‐PD numerical method to respectively judge the tensile and shear failure of rock materials. The effects of inclination angles and ligament angles on the crack initiation and coalescence modes for flawed rocks are investigated based on the numerical results. The numerical results are in good agreement with the previous experimental results. The fracture mechanism of flawed rocks is revealed based on the evolutionary distribution characteristics of the maximum principal stress field and shear stress field obtained by the extended NOSB‐PD theory. Highlights: The extended non‐ordinary state‐based peridynamics (NOSB‐PD) theory is employed.The fracture characteristics of flawed rocks are investigated by the extended NOSB‐PD.The fracture failure mechanism of flawed rocks is revealed by the extended NOSB‐PD. [ABSTRACT FROM AUTHOR]

To better solve the issues of steady crack extension with broad plasticity and the crack‐related problems in general yielding situations when the assumption of small‐scale plastic yielding fails, it is of great significance to further study the macroscopic mechanism of crack extension. In this paper, a new insight into the elastic–plastic crack extension is proposed on the foundation of critical storage of elastic strain energy (SESE). The feasibility of the new methodology is validated by designing and implementing two different experimental schemes in three typical elastic–plastic materials. The experimental results indicate that the critical SESE decreases linearly with the increase of crack length and U‐notch initial length. Besides, the SESE release rate is obtained through experimental and theoretical methods, and they are in the same order of magnitude and their value sequences are also accordant with all tested materials. Therefore, this investigation provides a new approach to characterizing crack extension in elastic–plastic materials. Highlights: A new insight is proposed to characterize crack growth in elastic–plastic materials.A novel experimental methodology is adopted to obtain the critical SESE.The established linear correlation is well validated by two experimental schemes.By experimental and theoretical methods, G is obtained and they fit each other well. [ABSTRACT FROM AUTHOR]

Multiaxial fatigue failure is the most common problem in engineering structures. It is worth noting that short crack growth accounts for most of the fatigue life. Hence, it is necessary to study the short crack growth models for multiaxial fatigue life assessment. The primary focus of this study is to develop a hierarchical Bayesian linear regression method to estimate parameters in multiaxial fatigue crack growth model. The Bayesian method is used to estimate the intercept and slope of the regression equation for each loading path and ensemble test datasets. The method of this work was demonstrated on three multiaxial fatigue crack growth datasets. The main results obtained in this paper were that the parameters of the multiaxial fatigue crack growth model changed significantly with different loading paths, and the parameters of the model depended on the multiaxial loading path. Highlights: An equivalent strain‐based intensity factor ΔKESA was proposed.Hierarchical Bayesian linear regression is developed for parameter estimation.Hierarchical Bayesian model considers the differences of each loading paths.The parameters of the fatigue crack growth model depend on the loading path. [ABSTRACT FROM AUTHOR]

In multiscale analysis, homogenization methods are needed to up‐scale the micromechanical response obtained from investigating the underlying microstructure to the next higher scale. The standard homogenization schemes are based on volume averaging over the entire microstructure following Hill's approach, which requires that the virtual energies generated on the two involved scales equalize. However, these standard homogenization schemes are not applicable to softening phenomena due to localization, and representativeness of the considered microscale volume is lost. One way to overcome these drawbacks is to perform the volume averaging only within the localizing failure zone. Thereby, representative results can be achieved even in the softening region. In this paper, we apply the failure zone homogenization approach to both, mode I and mode II loading scenarios, as well as mixed‐mode loading of long fiber reinforced plastics. For an accurate description of material failure within the epoxy matrix, a scalar damage model at large strains with gradient enhancement is used, such that the obtained results are mesh‐independent. As a result, we show that for all considered cases representative volume element (RVE) sizes can be determined by using the failure zone homogenization scheme. Nevertheless, the energy distributions of all involved mechanisms have to be considered carefully in order to allow generalizations. [ABSTRACT FROM AUTHOR]

Using artificial intelligence‐based methods in predicting material properties, in addition to high accuracy, saves time and money. This paper models and predicts the fracture toughness properties of polymer concrete (PC) composites using the deep learning method. After preparing a database consisting of 209 experimental data from 19 relevant studies, the effect of seven important variables on critical stress intensity factor (KIc) and crack tip opening displacement (CTOD) is considered. Then, the deep neural network (DNN) model is developed and trained using the prepared database. The accuracy of the DNN model is examined by implementing four statistical criteria, MSE, R2, RMSE, and MAE. Finally, the sensitivity of the KIc and CTOD to each input variable is evaluated using a partial dependence plot (PDP) analysis. While aggregate size, nanofiller content, and a/R ratio have the most positive effect on KIc, aggregates and nanofiller content have the most positive influence on CTOD. Highlights: An experimental database for fracture mechanics of polymer concrete (PC) is prepared.A deep neural network (DNN) model is developed to predict the fracture properties of PC.The effect of seven input variables on KIc and CTOD of PC is evaluated.The sensitivity of KIc and CTOD of PC is analyzed by using partial dependence plots. [ABSTRACT FROM AUTHOR]

This paper contains the in‐service fatigue fracture analysis for the first stage low‐pressure compressor disk of the aircraft engines D30KU‐154. Based on the results of the fractographic investigation on collapsed compressor disks the fatigue crack initiation and propagation principles were established. It is shown that the crack initiation in the rim part of the compressor disk is due to a high frequency loading that leads to very high cycle fatigue fracture. The total fatigue lifetime of the compressor disk is determined by simultaneous action of low amplitude loading due to blades vibration, and high amplitude loading due to flight cycle (centrifugal forces). Study of in‐service fracture of the compressor disk was based on the evaluation of numerical simulations of the stress state in the damaged zone under corresponding loading conditions. The estimation of fatigue lifetime and crack path predictions were performed based on the multiregime fatigue fracture model developed by the authors. Highlights: The two‐criteria multimode fatigue fracture model is introduced.The operational fatigue breaks in different aircraft structures are analyzed.The numerical simulations of compressor disk failure performed under different loading conditions and scenarios.The minimum fatigue lifetime was calculated for VHCF initiation and HCF crack growth scenario. [ABSTRACT FROM AUTHOR]

Hydraulic fracturing is the most widely used primary method for the stimulation of unconventional oil and gas resources. While knowledge of hydraulic fracture parameters is critical to reservoir productivity, predicting the fracture initiation is important for determining the complexity of the fracture network. Subcritical crack growth in reservoir rock plays an important role in forming fracture networks, but the understanding of the influence of fracturing conditions on subcritical crack growth is still lacking. In this paper, the subcritical crack growth behavior of sandstone and shale under ambient air, deionized (DI) water, and slick‐water conditions is studied. X‐ray diffraction analysis is done on the rock samples to determine their mineralogical composition, while tensile strength is measured by the Brazilian test. Then in Load Relaxation mode, a Double‐Torsion test (DT) is carried out under different conditions to study the subcritical crack growth of the samples. To further verify the influence of clay‐rich minerals, a similar analysis is performed on clay‐free granitic rock samples. The results of the tensile strength test and DT test demonstrate that the presence of clay minerals is the main reason for the difference in the subcritical crack growth behavior of shale and sandstone samples. DI water seems to better improve the subcritical crack growth compared with other test conditions. The value of the Subcritical Index (n) is smaller in a slick‐water environment than that in a DI water environment, revealing that slick water can better promote complex fracture propagation. [ABSTRACT FROM AUTHOR]

This paper presents a fully coupled thermo‐hydro‐mechanical (THM) model which simulates frost heave in fully saturated soils. The model is able to simulate the formation and growth of multiple distinct ice lenses. The basic equations of the system were derived using the continuum theory of mixtures, nonequilibrium thermodynamics, and fracture mechanics, considering skeleton deformation, water flow and heat transport. Central to this model is the coupled transport of mass due to the temperature gradient across the frozen fringe, which acts as the main driving force of the phenomenon. The model is formulated in terms of measurable physical properties and thus no ad hoc parametrization is required. In an ice‐lens‐free state, the system is solved as a continuum using the finite element method (FEM). It is then locally treated as a discontinuous system upon the formation of ice lens, by enriching the elements carrying the embedded ice lens(es) using the extended finite element method (X‐FEM). The accuracy and efficiency of the proposed model has been verified using several laboratory tests on Devon silt samples at different overburden pressures and thermal boundary conditions. Shut‐off pressures have been also estimated and compared with the experimental results. [ABSTRACT FROM AUTHOR]

This contribution introduces the work of early researchers in the field of fracture mechanics and materials testing. The development in fracture mechanics around the turn of the century in Germany and Austria-Hungary is presented, and the work of pioneers, e.g. K. Wieghardt, A. V. Leon, K. Wolf, A. Smekal and P. Ludwig is critically discussed. A comparison with the developments by G. I. Inglis and A. A. Griffith is elaborated. It will be shown that the work of these pioneers—particularly the 1907 paper by Wieghardt on the development of the basic analytical equations of fracture mechanics— predates many of the later developments by several decades. The work by Wieghardt was in fact directly related to a practical failure case, and the voluminous work of Leon was mainly driven by practical needs of engineering. The reasons for the neglect of Wieghardt's fundamental paper of 1907—particularly in the Anglo-American hemisphere—are critically discussed. [ABSTRACT FROM AUTHOR]

Unloading compliance (UC) method and normalization method (NM) are two of the most commonly used methods for determining the fracture toughness of materials. However, considerable differences often exist in the fracture toughness determined by these two methods, which solicits a new method to determine the fracture toughness accurately. In this paper, the compliance of crack length differences is discovered, analyzed, and verified by experiments. Based on this compliance, a new accurate method, known as the accurate J‐R curve method (AJR), is developed and verified by test results. It is found that the J‐R curves determined by the new AJR method are more accurate than those determined by UC and NM. The developed new AJR method and the results presented in this paper can assist engineers and researchers to determine J‐R curves and fracture toughness of steels more accurately and can contribute to the body of knowledge of fracture mechanics. [ABSTRACT FROM AUTHOR]

Numerical methods have been extensively applied to fracture mechanics, while they cannot simulate the problems without the mechanical models or constitutive equations. Artificial neural networks (ANNs) can be utilized to predict complex fracture problems, but these approaches require large amounts of data for the training. Therefore, in this paper, to combine the advantages of the numerical methods and the ANNs, an improved back propagation neural network (BPNN) is proposed by introducing the enrichment used in the numerical methods into the activation function utilized in the neural networks. The enrichment is able to represent the crack tip field which can accelerate the convergence. At the field near the crack tip, the improved BP solution can converge to the analytical solutions which validate the high accuracy of the proposed method. Without sufficient data, especially the data are missing in the near field of the crack tip, the improved BP method can also achieve high accuracy and convergence, while the conventional BP method may not converge to the predetermined error bound. Numerical simulations of the quasi‐static and fatigue crack problems demonstrate that the improved BP method can accurately predict the crack propagation and its growth rate with relatively little data. [ABSTRACT FROM AUTHOR]

Understanding deformations and fluid flow in fractured rocks is of central importance for many subsurface flow applications. Thus, numerical frameworks are needed that capture the coupled mechanical and hydraulic behaviour, including scenarios with complex fracture networks. This paper employs the extended finite volume method to represent fracture manifolds in a poroelastic matrix domain and to compute shear and tensile displacements of fracture segments. However, using embedded fractures with non‐conforming grids can lead to severe convergence issues while computing shear slip and tensile opening of intersecting and parallel fractures, particularly if they have similar slopes. Our proposed solution of this problem is to slightly deform the fracture geometry by merging critical segments. We discuss and show examples of which attributes the merged segment has to adopt to ensure the correct slip behaviour at an intersection. Thereby it is crucial that the flow topology remains unaltered. Analysing failures of kinked fractures and fracture intersections show the flexibility of the devised algorithm. Moreover, it is demonstrated that deformation and opening patterns of a natural network with more than 200 fractures are qualitatively predicted very well. This method is a simple solution to treat multiple fracture segments in a grid cell, hence it can be used for any model embedding fractures in non‐conforming grids. [ABSTRACT FROM AUTHOR]

Hydraulic fracture, whether a natural phenomenon or an engineered process, consists of a highly pressurized flow evolving within a rock and, when necessary, fracturing such a medium. Particularly, in the context of oil and gas exploitation, a mixture of water and proppant is injected through a well to improve the oil extraction conditions by artificially increasing the local permeability. From a modeling standpoint, it is fundamental to acknowledge that this complex flow involves, among other disciplines, fracture mechanics, fluid dynamics, non‐Newtonian flow, solid mechanics, and flow in porous media. Therefore, explicitly or not, a model bears multiple scales and multiple physics, leading to a non‐linear moving boundary mathematical problem that is hard to solve through analytical techniques. Amongst them, the Pseudo‐3D, which computes fracture evolution in reservoirs confined by symmetric stress barriers, is frequently employed in the oil and gas industry domain. The different assumptions made to obtain the P3D model lead to inaccurate predictions, like the overestimation of fracture height for important operating conditions. We propose a model discrepancy term in a multi‐fidelity approach to correct such drawbacks. The main difficulty associated is constructing a mapping between the inputs and outputs that faithfully represents the error between high and low fidelity models. In this paper, we investigated the performance of a nonlinear multi‐fidelity approach relying on Gaussian Processes. We present a careful analysis to assess the good performance of such a proposition and also present results involving Uncertainty Quantification, which is made feasible by using the bi‐fidelity surrogate. [ABSTRACT FROM AUTHOR]

The additional local stress concentration caused by undercut and misaligned defects could lead to lower fatigue strength of welded joints. The paper aims to investigate the effects of undercuts and misalignments on fatigue performance and reliability of Load‐carrying Cruciform Welded Joint (LCWJ) quantitatively by probabilistic statistics theory and fracture mechanics theory. Firstly, the geometrical characteristics of undercut and misalignment are summarized from the literature and our experiments. Subsequently, the probabilistic distributions of material fracture properties, the configurations of geometries, and flaws were evaluated under specific loading conditions. The fatigue strengths are further estimated by the probabilistic reliability theory by combining the actual fatigue data. The results demonstrate a clear disparity of fatigue crack growth threshold and resistances for the tested data of base metal and weldment. The level of defects determines the interval of fatigue life, and the larger the dispersion accompanying earlier fatigue failure occurs. Highlights: The effects of weld defects on fatigue strength and reliability were assessed quantitatively by the probabilistic method.FCGRs of HAZ and U‐WM are more conservative than the base metal.The SIFs in mismatched LCWJs were evaluated by the weight function theory. [ABSTRACT FROM AUTHOR]

The text discusses the Eighth International Conference on Very High Cycle Fatigue (VHCF8), which was held online from July 5 to 9, 2021, and distributed from Sapporo, Japan. The conference focused on the emerging issue of very high cycle fatigue (VHCF) in materials strength, particularly in metallic materials, polymers, and composites. The conference covered a wide range of topics, including crack initiation and propagation mechanisms, fatigue life estimation, and nondestructive approaches for internal damage analyses. After the conference, 17 high-quality papers were selected for a special issue of the journal Fatigue and Fracture of Engineering Materials and Structures (FFEMS) to highlight the research presented at the conference. [Extracted from the article]

Crack behavior at the interface between two materials is the core problem of layered material fracturing. In this paper, first, experimental tests were conducted on layered material using a drop weight test system following the caustics method. The layered material was made of poly (methyl methacrylate) (PMMA) and epoxy resin bonded with Loctite‐330 at two inclination angles (30° and 60°). A corresponding numerical simulation was carried out using continuum–discontinuum element methods. Crack propagation is found to mainly occur in mode I in the PMMA and epoxy resin but follows a mixed cracking mode at the interface. The fracture parameters of the crack tip in the layered materials changed substantially owing to the existence and change of the interface structure. After the crack enters the interface, the crack propagation speed increases significantly. Higher crack dip angles are associated with greater crack propagation speed increases after entering the interface. The simulation results indicate that the interface strength properties affect crack behavior at the interface. This effect also varies as a function of interface inclination and impact velocity. Highlights: Caustics method is used to study fracture parameters of layered material.A mixed‐mode fracture model is implemented into CDEM to simulate interface crack.Effect of strength properties on interface crack are simulated.Effect of impact velocity on interface crack are simulated. [ABSTRACT FROM AUTHOR]

Considering fracture constraint is an efficient way to describe stress-strain field and fracture toughness more accurately, so it is necessary to realise the relationship with in-plane and out-of-plane constraint for different standard specimens. In this paper, three-dimensional finite element method is applied to study the in-plane and out-of-plane constraint for both cruciform specimen and single edge notched bending specimen made from commercial pure titanium. Crack length and in-plane loading as the factors affecting in-plane constraint, and thickness as the factor affecting the out-of-plane constraint are used to study the effect on both in-plane and out-of-plane constraint in this paper. From the results, in-plane and out-of-plane constraint are both related to specimen geometries and loading styles. And there exist relationships with in-plane and out-of-plane constraint because of factors for different specimens. Depending on crack length, out-of-plane constraint increases with in-plane constraint. While depending on transverse loading, out-of-plane constraint decreases with in-plane constraint. In addition, when the in-plane constraint of a specimen is higher, in-plane constraint increases with out-of-plane constraint (thickness). When the in-plane constraint is lower, in-plane constraint almost remains unchanged with out-of-plane constraint. [ABSTRACT FROM AUTHOR]

Using a robust three‐dimensional generalized/eXtended finite element method (G/XFEM) algorithm, this paper presents a comprehensive study on multiple hydraulic fracture propagation and their interactions under different treatment conditions. Aimed at capturing the complex multiphysics behavior, the resulting nonplanar fracture footprints under mixed‐mode conditions are simulated using a formulation, which couples the solid/rock domain equations and the fluid flow within the fractures/crevices. Due to the small length scale of the fracture process zone relative to the surrounding formation size, as typically encountered in tight shale reservoirs, linear elastic fracture mechanics based on a regularized Irwin criterion is adopted to describe the fractured solid/rock response while a power law is used for the fluid flow by assuming a Newtonian fluid behavior. Equipped with the capability for mesh adaptivity and automatic time step search algorithms, the G/XFEM utilized to discretize the resulting system of coupled nonlinear equations allows the adoption of independent meshes for the background solid domain and the fracture surfaces without any matching/compatibility requirement between the two. Fracture propagation directions are decided based on the modes I, II, and III stress intensity factors that are extracted using the displacement correlation method. The presented model is first applied to a pair of misaligned fractures and then to an array of en échelon fractures for qualitative verification against a literature prediction by the boundary element method (BEM) and an observed field behavior, respectively. Next, simulation of several sets and configurations of multiple hydraulic fractures, resulting in a total of 23 parametric studies, are carried out to investigate the influences of fracture spacing, injection fluid viscosity, number of fracture clusters, and the type of remote stress conditions. [ABSTRACT FROM AUTHOR]

This paper evaluates the capabilities of the recently developed CF20 cohesive fatigue model, which can predict crack initiation as well as the rates of crack propagation by relying on intrinsic relationships between a stress‐life diagram and its corresponding Paris law. The model is validated here using a partially reinforced double cantilever beam (R‐DCB) benchmark proposed in literature. The two parameters needed for the CF20 cohesive fatigue model were obtained by performing preliminary analyses of a conventional DCB. The analysis results indicate that the CF20 cohesive fatigue model can accurately reproduce the complex evolution of the delamination observed in the R‐DCB. Highlights: A 3D benchmark is analyzed using the mixed‐mode CF20 cohesive fatigue formulation.The parameters of the model are obtained from experimental results of DCB specimens.The model predicts crack growth rate and delamination shape changes during propagation.A parametric study illustrates the precision needed to accurately predict the final delamination length. [ABSTRACT FROM AUTHOR]

This paper presents a new model for anisotropic damage in bedrock under the combined influences of biotite weathering, regional stresses, and topographic stresses. We used the homogenization theory to calculate the mechanical properties of a rock representative elementary volume made of a homogeneous matrix, biotite inclusions that expand as they weather, and ellipsoidal cracks of various orientations. With this model, we conducted a series of finite element simulations in bedrock under gently rolling topography with two contrasting spatial patterns in biotite weathering rate and a range of biotite orientations. In all simulations, damage is far more sensitive to biotite weathering than to topographic or regional stresses. The spatial gradient of damage follows that of the imposed biotite weathering rate at all times. The direction of micro‐cracks tends to align with that of the biotite minerals. Relative to the topographic and regional stresses imparted by the boundary conditions of the model, the stress field after 1,000 years of biotite weathering exhibits higher magnitudes, wider shear stress zones at the feet of hills, more tensile vertical stress below the hilltops, and more compressive horizontal stress concentrated in the valleys. These behaviors are similar in simulations of slowing eroding topography and static topography. Over longer periods of time (500 kyr), the combined effects or weathering and erosion result in horizontal tensile stress under the hills and vertical tensile stress under and in the hills. These simulations illustrate how this model can help elucidate the influence of mineral weathering on Critical Zone evolution. Plain Language Summary: In bedrock, stresses are generated through a combination of chemical weathering, topography, and tectonic forces. Together, these disaggregate minerals and redistribute stress, thereby damaging the rock. In this study, we focus on the sensitivity of rock damage to the weathering of biotite, which expands as it weathers and pushes on the surrounding minerals. We propose a micro‐mechanical model in which small cracks grow in response to biotite weathering. The mechanical properties of the bulk rock are obtained by homogenization. With this model, we conducted a series of finite element simulations in bedrock under gently rolling topography, two contrasting spatial patterns in biotite weathering rate, and a range of biotite orientations. In our simulations, the spatial distribution of rock damage always follows that of biotite weathering. This shows that crack growth is far more sensitive to biotite weathering than to the topographic or regional stresses applied in these simulations. These simulations also highlight the importance of the direction of the biotite minerals relative to the regional stress field. Together, these simulations show that biotite weathering is capable of dominating the development of bedrock damage. More generally, these simulations show that the proposed model can be used as a tool to explore the influence of mineral weathering on Critical Zone evolution. Key Points: We present a new model for anisotropic rock damage under the influences of biotite weathering, regional stresses, and topographic stressesSimulations show that under common topographic and tectonic conditions, microcrack propagation can be far more sensitive to biotite weathering than far‐field stressesBiotite weathering produces shear stress zones at the bottom of hillslopes, vertical tension below hilltops and horizontal compression in valleys [ABSTRACT FROM AUTHOR]