Mechanics of Materials最新文献

{"title":"Modelling of interfacial debonding between FRP and concrete using the scaled boundary finite element method","authors":"Runyan Du ,&nbsp;John Orr ,&nbsp;Zhenjun Yang ,&nbsp;Zihua Zhang","doi":"10.1016/j.mechmat.2026.105622","DOIUrl":"10.1016/j.mechmat.2026.105622","url":null,"abstract":"<div><div>Interfacial debonding between fibre-reinforced polymer (FRP) and concrete is one of the most common failure modes in externally bonded FRP (EB-FRP) strengthened concrete structures, typically occurring within a thin layer of concrete near the interface. This study uses the scaled boundary finite element method (SBFEM), a semi-analytical numerical approach, to model the interfacial debonding process between FRP and concrete. The quadtree meshing scheme is used to smooth the mesh transition near the interface, and high computational efficiency is achieved by exploiting the advantages of SBFEM. The Mazars damage model, which considers the tensile and compressive damage separately, is integrated with a nonlocal model to eliminate mesh sensitivity, thereby enabling the accurate prediction of damage evolution in the concrete substrate. Several benchmarks, including three-point bending notched beams (TPBNB), a double-notched tension beam (DNTB) and single shear FRP-concrete specimens, are simulated to confirm the effectiveness and reliability of the proposed method. The numerical results align closely with both the experimental data and finite element modelling. Furthermore, the effects of internal length, bond length, FRP stiffness, and concrete strength on the interfacial bonding performance are investigated. The existence of the effective bond length and its relation to the bond length are confirmed. The results also reveal that the failure mode of the interface is sensitive to the internal length and that the ultimate debonding load depends critically on both FRP stiffness and concrete strength.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"215 ","pages":"Article 105622"},"PeriodicalIF":4.1,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146078161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stability of extrinsic cohesive-zone model with penalty-based contact in explicit dynamic fragmentation simulations","authors":"Thibault Ghesquière-Diérickx,&nbsp;Jean-François Molinari,&nbsp;Guillaume Anciaux","doi":"10.1016/j.mechmat.2025.105581","DOIUrl":"10.1016/j.mechmat.2025.105581","url":null,"abstract":"<div><div>Dynamic fragmentation simulations are essential for predicting material response at high strain rates, yet explicit dynamic simulations that combine an extrinsic cohesive-zone model (CZM) with penalty-based contact often exhibit severe instabilities. In a two-dimensional benchmark, we observe exponential energy growth and resulting artificial fragmentation under standard contact penalty settings and time step choices, which motivates a systematic analysis of instability sources. Three mechanisms are isolated and quantified: (i) diverging initial cohesive stiffness, which constrains the stable time step; (ii) discontinuous stiffness jumps at the cohesive–contact interface; and (iii) discontinuity introduced by cohesive softening. Analytical error estimates, phase-space diagnostics, and energy growth metrics reveal that repeated cohesive–contact switching can accumulate small per-step energy errors into long-term energy drift. Within the explored parameter space, maintaining stability requires time steps well below the usual limit. To mitigate these energy artifacts, we assess an adaptive penalty strategy that ties the contact stiffness to the evolving cohesive stiffness. This modification eliminates the discontinuity and restores energy conservation, but it allows larger interpenetration, making it suitable as a diagnostic rather than a definitive remedy. Overall, our study identifies the root causes of unphysical energy drift and demonstrates that penalty-based contact is not a viable approach for long-term, energy-consistent fragmentation simulations with physically meaningful fragment statistics.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"215 ","pages":"Article 105581"},"PeriodicalIF":4.1,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145928287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the evaluation of in-situ mechanical properties of an additively manufactured BCC lattice","authors":"Malo Valmalle ,&nbsp;Benjamin Smaniotto ,&nbsp;Junhe Lian ,&nbsp;Luc St-Pierre ,&nbsp;François Hild","doi":"10.1016/j.mechmat.2026.105602","DOIUrl":"10.1016/j.mechmat.2026.105602","url":null,"abstract":"<div><div>Additive manufacturing enables for the fabrication of complex lattice materials with superior strength-to-weight ratios. These lattice structures are made from small struts that are difficult to test individually and whose responses may be size-dependent. In the present work, the mechanical response of a BCC lattice was studied when subjected to <em>in-situ</em> compression, <em>i.e.,</em> monitored via Digital Volume Correlation (DVC). Backtracking was implemented in the DVC procedure to account for geometric imperfections generated by the manufacturing process. Displacement fields were measured via DVC and then employed in a Finite Element Model Updating (FEMU) procedure to calibrate the parameters of the constitutive law. Numerical simulations with the calibrated parameters were found to be in good agreement with experiments. The lattice material had a lower strength than that reported in the literature and measured with <em>ex-situ</em> tensile tests. This difference is attributed to size effects; this work demonstrates that they can be accounted for and that a single <em>in-situ</em> test is sufficient to calibrate such material properties.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"215 ","pages":"Article 105602"},"PeriodicalIF":4.1,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Plasticity and fracture properties of laser powder bed fusion fabricated 316L stainless steel - Experimental and numerical investigations","authors":"Jian Liu ,&nbsp;Guobin Li ,&nbsp;Cunyi Li ,&nbsp;Chuanqiang Li ,&nbsp;Jianguang Fang","doi":"10.1016/j.mechmat.2026.105597","DOIUrl":"10.1016/j.mechmat.2026.105597","url":null,"abstract":"<div><div>To understand the complex mechanical behaviour of Laser Powder Bed Fusion (LPBF) fabricated 316L stainless steel (LPBF-316L), its anisotropic plasticity and ductile fracture are systematically investigated under various stress states and strain rates in this study. For comparison, tensile tests are also conducted on traditionally rolled 316L stainless steel (TR-316L) samples. Based on the experimental results, the transversely isotropic Hill-48 yield criterion and a modified Johnson-Cook (J-C) plasticity model are calibrated to describe the dynamic and anisotropic plastic response. Scanning electron microscopy reveals that fracture morphology is strongly influenced by stress state, strain rate, and build orientation, with void coalescence and dimple formation indicative of ductile failure, alongside manufacturing-induced defects. Additionally, a modified Mohr-Coulomb criterion (MMC) is proposed to characterise both anisotropic fracture initiation and strain rate sensitivity. A combination of experimental and numerical approaches is employed to capture the evolution of stress and strain fields during deformation. Finally, a comparative analysis of the three-dimensional fracture envelopes of TR-316L and LPBF-316L samples is performed. It is found that LPBF-316L exhibits lower sensitivity to the average normalised Lode angle than TR-316L. This study offers critical insight into the mechanical performance of additively manufactured metallic materials and informs the development of predictive models for advanced structural applications.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"215 ","pages":"Article 105597"},"PeriodicalIF":4.1,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145928350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of iterated variational homogenization for microstructure evolution in porous materials","authors":"R. Vigneshwaran,&nbsp;A.A. Benzerga","doi":"10.1016/j.mechmat.2026.105616","DOIUrl":"10.1016/j.mechmat.2026.105616","url":null,"abstract":"<div><div>The purpose of this work is to assess iterated variational homogenization estimates of the evolution of relative lengths and axes of ellipsoidal pores under unhomogeneous yielding. The latter is generally understood as the percolation of elastically unloaded zones in a porous material. To this end, the instantaneous average strain rate and rotation rate of the pores are calculated by requiring the overall strain rate to be congruent with unhomogeneous yielding. The predictions are then compared against numerically determined strain and rotation rates of the pores using finite element based limit-analysis. The two fundamental modes of unhomogeneous yielding are considered: opening/closure and sliding. We discuss in particular whether the predictions capture the extreme shearing of pores under sliding or the lateral bulging of pores under opening. For the opening mode, iterated variational homogenization performs well in predicting lateral bulging, except for nearly spherical pores. For sliding shear, the iterated variational homogenization estimates are qualitatively inaccurate and consistently underpredict the shearing and rotation rates of the pores. It is shown that simpler estimates from linear variational homogenization, augmented with ‘complementary’ concentration tensors, compare favorably with numerical results.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"215 ","pages":"Article 105616"},"PeriodicalIF":4.1,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146078224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The role of chain stretch heterogeneity on the uniaxial failure response of rubbery networks","authors":"Lucas Mangas Araujo,&nbsp;Laurence Brassart","doi":"10.1016/j.mechmat.2026.105599","DOIUrl":"10.1016/j.mechmat.2026.105599","url":null,"abstract":"<div><div>The macroscopic failure response of rubbery networks such as elastomers and hydrogels involves the scission of individual polymer chains, mediated by the network topology. However, the precise mechanisms by which individual chain scission events result in macroscopic failure remain poorly understood. In this work, we use Discrete Network (DN) simulations to investigate failure mechanisms in model random networks in uniaxial tension. Our DN simulation results suggest that macroscopic failure, characterised by a sharp drop in the macroscopic stress–stretch response, only requires the scission of a small fraction of chains in a localised region of the network, even in perfect monodisperse networks. Localised failure is triggered by pre-existing heterogeneities in the chain stretch and is further modulated by network parameters such as the chain length or chain strength. Simple micromechanical models of rubber elasticity, such as the three-chain and eight-chain models, fail to capture the onset of damage because they do not capture the chain stretch heterogeneity. More sophisticated microsphere theories in their affine and non-affine versions only partially address this shortcoming. Overall, our results provide new insights into failure mechanisms of rubbery networks, while providing reference results useful for the validation of improved constitutive theories.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"215 ","pages":"Article 105599"},"PeriodicalIF":4.1,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145928233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of soft materials with cylindrical cavity pores via indentation technique","authors":"Haoyuan Che ,&nbsp;Zepu Liu ,&nbsp;Fei Jia ,&nbsp;Jian Sun ,&nbsp;Yanju Liu","doi":"10.1016/j.mechmat.2026.105620","DOIUrl":"10.1016/j.mechmat.2026.105620","url":null,"abstract":"<div><div>Soft materials with designed pore structures often exhibit superior properties, becoming increasingly important in advanced applications such as metamaterials and soft robotics. Quantitative characterization of the intrinsic mechanical properties of defect-containing soft materials is crucial for optimizing their performance. This study investigates spherical indentation for soft materials with cylindrical cavity defects. In contrast to the response of bulk materials, a critical load <span><math><msub><mrow><mi>P</mi></mrow><mrow><mn>1</mn></mrow></msub></math></span> is identified from the load–displacement curve of the indentation test, at which the insertion-induced instability occurs. This is followed by a load decay and subsequent stabilization to <span><math><msub><mrow><mi>P</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span> in regions sufficiently remote from the cavity termini. By combining dimensional analysis with finite element method, the explicit expressions relating <span><math><msub><mrow><mi>P</mi></mrow><mrow><mn>1</mn></mrow></msub></math></span> and <span><math><msub><mrow><mi>P</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span> to material parameters and friction coefficients are determined. An indentation method is subsequently developed to evaluate the shear modulus <span><math><msub><mrow><mi>μ</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span> and friction coefficient <span><math><mi>f</mi></math></span> simultaneously. Optimal parameter space of normalized cavity radius <span><math><msub><mrow><mover><mrow><mi>R</mi></mrow><mrow><mo>̄</mo></mrow></mover></mrow><mrow><mtext>h</mtext></mrow></msub></math></span> and <span><math><mi>f</mi></math></span> is preliminarily determined to provide guidance for the indentation tests and avoid the absence of <span><math><msub><mrow><mi>P</mi></mrow><mrow><mn>1</mn></mrow></msub></math></span> or the phenomenon of self-contact. The effectiveness of the proposed method is validated experimentally. By combining finite element analysis with theory of contact mechanics, we analyze the evolution of the load <span><math><mi>P</mi></math></span> during indentation process. Experiments on specimens with multiple cavities show that the method remains reasonably effective for specimens containing multiple cavities. Through the incorporation of the Ogden hyperelastic model into finite element simulations, the method’s sensitivity to strain hardening is evaluated, confirming its robust performance for typical soft materials. Finally, an approximate expression for the stabilized load <span><math><msub><mrow><mi>P</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span> under low-friction conditions is derived, and the adhesive stress is further considered in the indentation method for cases involving low friction and relatively small adhesive stress.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"215 ","pages":"Article 105620"},"PeriodicalIF":4.1,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146024178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Uniaxial Mechanochemical Coupling Model for Chemical Bond Scission-Triggered Self-Strengthening in Double-Network Hydrogels","authors":"Xinbo Liu,&nbsp;Haibao Lu","doi":"10.1016/j.mechmat.2026.105625","DOIUrl":"10.1016/j.mechmat.2026.105625","url":null,"abstract":"<div><div>Although weak chemical bonds are anticipated to diminish the mechanical strength of soft matter, recent studies have demonstrated that introducing weak bonds to trigger mechanoradical polymerization enables the synthesis of a new type of rapid self-strengthening double-network hydrogel (RSS DN hydrogel), offering a novel strategy for designing high-strength soft matter. However, the working mechanisms underlying the self-strengthening and rate-dependent behavior remain unclear. In this study, a mechanochemical rate-dependent model, which combines mechanoradical polymerization and a dynamic multi-network framework, has been developed for the RSS DN hydrogels. A free energy equation is initially formulated based on the inverse Langevin statistical theory to describe the interpenetrating multi-networks. Then, the kinetics of the mechanochemical reaction is introduced to characterize the bond scission, in which the mechanoradical polymerization theory is employed to describe the polymerization kinetics of newly formed networks. Finally, the effectiveness of the proposed model is validated by uniaxial experimental data in the reported literature. The model captures the rate dependence of bond scission-triggered self-strengthening, and provides a physical insight into the complex mechanochemical coupling effect and strengthening principle in RSS DN hydrogels.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"215 ","pages":"Article 105625"},"PeriodicalIF":4.1,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146170108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A spatio-temporally adaptive asynchronous variational integrator for a phase field model of dynamic fracture","authors":"Deepak B. Jadhav ,&nbsp;Dhananjay Phansalkar ,&nbsp;Kerstin Weinberg ,&nbsp;Michael Ortiz ,&nbsp;Sigrid Leyendecker","doi":"10.1016/j.mechmat.2026.105604","DOIUrl":"10.1016/j.mechmat.2026.105604","url":null,"abstract":"<div><div>Phase field modeling of fracture is an effective approach for simulating crack propagation. However, the presence of a length scale parameter in the phase field model requires a uniformly fine mesh, leading to high computational costs, especially in dynamic simulations where the global time step is determined by the smallest spatial mesh element. A recently proposed asynchronous variational integrator (AVI) for the phase field modeling of dynamic fracture addresses this by allowing each spatial element to evolve with an independent time step. In this approach, mechanical fields are updated at every time step, while the phase field is updated only after the displacement update of the largest spatial mesh element, reducing the computational costs. We build upon this formulation by incorporating spatial adaptivity, refining the mesh based on a criterion guided by the phase field variable. This leads to a spatio-temporally adaptive AVI for the phase field model of dynamic fracture, with spatial adaptivity driven by the phase field evolution and temporal adaptivity inherently provided by the AVI. Benchmark studies show that the proposed method reduces computational costs while accurately capturing dynamic fracture behavior.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"215 ","pages":"Article 105604"},"PeriodicalIF":4.1,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Micromechanical modeling of the nonlinear behavior of lightweight aggregate concrete — Failure under multiaxial loading conditions","authors":"Slim Kammoun ,&nbsp;Bilel Miled ,&nbsp;Ali Ellouze ,&nbsp;Karim Miled","doi":"10.1016/j.mechmat.2026.105628","DOIUrl":"10.1016/j.mechmat.2026.105628","url":null,"abstract":"<div><div>This paper presents a micromechanical model to predict the quasi-brittle behavior of Lightweight Aggregate Concrete (LWAC) under uniaxial and multiaxial loadings. The model integrates the incremental mean-field homogenization theory with continuum damage mechanics, focusing on LWAC filled with varying combinations of fine and coarse expanded clay (EC) aggregates. To simplify the modeling of EC aggregates with different densities, the concept of Fictitious Equivalent Inclusion (FEI) is introduced. Each LWAC sample is represented as a two-phase composite within a Representative Volume Element (RVE), consisting of a reference concrete matrix and a volume fraction of FEI. The incremental Mori–Tanaka model predicts stress and strain phase averages in the RVE, while the cementitious matrix follows Mazars’s <span><math><mi>μ</mi></math></span>-damage model coupled with fracture energy regularization. A confinement coefficient, accounting for triaxiality and porosity, enhances the model’s accuracy under multiaxial loadings. FEI, treated as softer than the matrix, exhibit elastic behavior. The model is validated against experimental data from literature, showing promising predictions for uniaxial, biaxial, and triaxial compression responses of LWC samples with various densities.</div></div>","PeriodicalId":18296,"journal":{"name":"Mechanics of Materials","volume":"215 ","pages":"Article 105628"},"PeriodicalIF":4.1,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146078162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}