International Journal of Non-Linear Mechanics最新文献

{"title":"Constitutive modeling of rock failure behavior under pressure conditions spanning the brittle–ductile transition","authors":"Sili Liu ,&nbsp;Lurong Hua ,&nbsp;Qizhi Zhu ,&nbsp;Jin Zhang ,&nbsp;Qiaojuan Yu ,&nbsp;Shuai Zhao ,&nbsp;Lunyang Zhao","doi":"10.1016/j.ijnonlinmec.2025.105117","DOIUrl":"10.1016/j.ijnonlinmec.2025.105117","url":null,"abstract":"<div><div>The brittle–ductile transition is a fundamental mechanical characteristic of rocks in a range of engineering applications. While various constitutive models have been proposed to predict rock failure, only a few are capable of quantitatively capturing the brittle–ductile transition. Moreover, to date, few existing models are able to uniformly describe the distinct mechanical behaviors of rocks in the brittle and ductile regimes. This paper presents a unified elastoplastic damage model capturing the mechanical behavior of rocks spanning the brittle–ductile transition. A subtly single cap-type plastic yield criterion is formulated in the effective stress space and a monotonic hardening function is introduced into the yield criterion to describe pre-peak hardening behavior accurately. The post-peak softening behavior is solely due to material damage, for which we propose a damage criterion. Unlike prevailing models, our hypothesis suggests that the damage process begins with localized cracking after reaching the peak stress, eliminating any accumulation of damage prior to the peak stress. In this context, the yield surface at peak stress state constitutes the real strength envelope. Furthermore, to accurately replicate post-peak softening behavior and brittle–ductile transition in rocks, we establish a theoretical correlation between residual damage and confining pressure. Numerical simulations are performed for three types of rock subjected to conventional triaxial compression. Comparisons between numerical predictions and test data demonstrate that the model effectively captures key features of mechanical behavior observed in these rocks. Particularly noteworthy is its ability to simulate the brittle–ductile transition.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"175 ","pages":"Article 105117"},"PeriodicalIF":2.8,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transverse and axial vibrations of masonry beams and towers","authors":"Maria Girardi","doi":"10.1016/j.ijnonlinmec.2025.105086","DOIUrl":"10.1016/j.ijnonlinmec.2025.105086","url":null,"abstract":"<div><div>Studying the effects of the earthquakes’ vertical component on the dynamic response of masonry buildings is still an open issue. This subject is investigated using a simplified masonry-like beam model with a generalized stress–strain relationship. The nonlinear dynamic equations that couple the transverse and axial oscillations of the beam are solved numerically. Some examples are presented and discussed, focusing on the structural typology of masonry towers and the recent earthquakes that threatened the North-Central Apennines in Italy.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"175 ","pages":"Article 105086"},"PeriodicalIF":2.8,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143868975","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stability analysis of a spline-rotor system subjected to friction-induced self-excited vibrations","authors":"Peng Cao ,&nbsp;Runze Zhang ,&nbsp;Ye Wei ,&nbsp;Baian Hu ,&nbsp;Xinxing Ma ,&nbsp;Zhenguo Zhang","doi":"10.1016/j.ijnonlinmec.2025.105127","DOIUrl":"10.1016/j.ijnonlinmec.2025.105127","url":null,"abstract":"<div><div>Spline joints introduce cross-coupling, internal friction, and interface discontinuities, that can lead to system instability and self-excited vibrations under certain operating conditions. Predicting the onset conditions and amplitudes of self-excited vibrations in the spline-rotor system, as well as their dependence on physical parameters such as misalignment and interfacial friction, is crucial for effective design work. Therefore, in this study, a comprehensive stability analysis of a spline-rotor system subjected to self-excited vibrations induced by interfacial friction is carried out. First, the complex eigenvalue method is used to identify the equilibrium point stability. Then, numerical continuation methods are applied to perform a global stability assessment and to rapidly predict limit cycles. To improve computational efficiency, model reduction is integrated, which allows a systematic investigation of the effects of parameters on system stability and vibration response, elucidating the friction mechanism and influence laws. Through this in-depth study, the stability and nonlinear behavior of the spline rotor system subjected to self-excited vibration is revealed, providing crucial theoretical support for effective design strategies to mitigate system instability and self-excited vibration in rotating machinery.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"175 ","pages":"Article 105127"},"PeriodicalIF":2.8,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143852030","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling photo-oxidation effects in semicrystalline polymer: Boundary-value simulations and experimental multiscale analysis","authors":"Ali Kassab ,&nbsp;Georges Ayoub ,&nbsp;Mustapha Makki ,&nbsp;Christopher Pannier ,&nbsp;Moussa Nait Abdelaziz","doi":"10.1016/j.ijnonlinmec.2025.105124","DOIUrl":"10.1016/j.ijnonlinmec.2025.105124","url":null,"abstract":"<div><div>This study presents a comprehensive computational framework designed to capture the mechanical property changes and damage accumulation in UV-aged semicrystalline polymers. The approach integrates time-dependent continuum damage mechanics with anisotropic plasticity and damage, implemented through user-defined subroutines in commercial finite element analysis (FEA) software. To account for UV-induced photo-oxidation, we introduce an experimentally informed photodegradation kinetics model, seamlessly coupled with the continuum damage mechanics formulation. Our focus is on semi-crystalline Low-Density Polyethylene (LDPE) films subjected to accelerated ultraviolet (UV) aging. Through extensive mechanical and rheological characterizations, we propose competing multi-scale mechanisms to describe the observed material behavior: initial strengthening, driven by chemi-crystallization, is followed by softening due to the formation of chemical cracks as UV exposure increases. The continuous decrease in strain to failure is attributed to oxidation-induced chain scission. The developed model is validated through FEA boundary-value problems modeling the experimentally tested samples. Comparative analysis between the simulated and experimental results highlights the model's accuracy in predicting mechanical behavior, damage progression, and fracture initiation. Overall, the proposed computational framework, along with its finite element implementation, delivers reliable and experimentally validated predictions.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"175 ","pages":"Article 105124"},"PeriodicalIF":2.8,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nonlinear stochastic evolution of spatial uncertainty along the process axis","authors":"N. Malkiel ,&nbsp;O. Rabinovitch","doi":"10.1016/j.ijnonlinmec.2025.105125","DOIUrl":"10.1016/j.ijnonlinmec.2025.105125","url":null,"abstract":"<div><div>This paper builds upon the existing concept of process axis analysis in strongly nonlinear structural problems by introducing a novel approach for assessing the evolution of spatial uncertainty. Specifically, it adapts the stochastic perturbation method to enable Random Field representation of uncertainty and analyze its effect along the process axis. As an example, the delamination process of a composite beam bonded to a substrate using an adhesive layer is looked at. The strongly nonlinear physical behavior and the uncertainty that accompanies such behavior are investigated along the axis of the nonlinear delamination process. This approach is innovatively developed to allow a random field representation of uncertainty by the adaptation of the stochastic perturbation method to the process axis analysis. Numerical results are compared with reference ones obtained by quadrature-rule numerical integration and Monte Carlo simulation. The ability to handle strongly nonlinear problems while avoiding the singularity and divergence of the stochastic analysis near snap-through and snap-back folds, achieved by means of the projection of the stochastic perturbation method to the process axis, and the representation of the parametric and spatial uncertainties of the structural properties by Random Fields are among the innovative and original contributions of the present work.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"175 ","pages":"Article 105125"},"PeriodicalIF":2.8,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143852029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"FEM-SPH adaptive method for dynamic analysis of the diaphragm's fracture in hypersonic impulse facilities","authors":"Jiahao Zhang,&nbsp;Linjie Huang,&nbsp;Zixuan Wan,&nbsp;Xia Song,&nbsp;Gun Li,&nbsp;Jiang Lai","doi":"10.1016/j.ijnonlinmec.2025.105123","DOIUrl":"10.1016/j.ijnonlinmec.2025.105123","url":null,"abstract":"<div><div>The shock tunnel is a key land-based test facility used to study the aerodynamic performance of supersonic aircraft. The diaphragm is an essential component of the shock tunnel test, which acts as the trigger device. The critical rupture pressure of the diaphragm is significant because it determines the operating conditions for the shock tunnel test. However, when the diaphragm ruptures, it generates fragments that can pose risks to the safe operation of the test equipment. The finite element method (FEM) is the most commonly used approach for analyzing the dynamic response of diaphragm rupture. While FEM can accurately predict the critical rupture pressure and rupture time, it has limitations in simulating the fragments produced during the rupture process. This paper proposes a method for calculating the dynamic response of a shock tunnel diaphragm rupture by combining the finite element method and smoothed particle hydrodynamics (FEM-SPH) to address this limitation. This method has been verified for its accuracy in predicting critical rupture pressure and time. Additionally, the paper introduces a research method for characterizing the fragments using aggregated SPH particles. It analyzes the dynamic response characteristics of the diaphragm and the pieces during the rupture process.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"175 ","pages":"Article 105123"},"PeriodicalIF":2.8,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143852027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A pseudo-compressible dual 4-chain model of polymer networks for exploring rubber elasticity","authors":"Ziyu Xing","doi":"10.1016/j.ijnonlinmec.2025.105122","DOIUrl":"10.1016/j.ijnonlinmec.2025.105122","url":null,"abstract":"<div><div>Rubber elasticity has been a subject of studies for an extended period of polymer physics. Currently, the advancement of rubbery polymers is proceeding at an accelerated pace, and the network structure is exceptionally complex. To comprehensively comprehend the mechanical behavior exhibited by these rubbery materials, it is imperative to further evolve the theoretical framework of rubber elasticity. To understanding this problem, this study introduces a pseudo-compressible dual four-chain model for analyzing polymer networks and rubber elasticity. To address the lack of periodicity in the 4-chain model, a pseudo-compressible dual four-chain model is constructed, which accounts for intrinsic moments and volume effects. The model assumes isotropic of the polymer and affine motion of crosslinking points, which changed the coordinate system, leading to a simplified 4-chain model. Due to the poor symmetry of the 4-chain model, the force balance caused by chain deformation is different from that of traditional Langevin statistics models. Based on the phantom network model, preliminary estimates of volume effects were made using phenomenology and scaling equations. The proposed model is validated against experimental data from literature on various mechanical tests, including compressibility, uniaxial tension, uniaxial compression, pure shear, equi-biaxial tension, and biaxial strain tests. Using uniaxial tensile data from literature, the fitting results of different models (proposed dual 4-chain model, <em>p</em>-chain model, Yeoh model, Anssari-Benam model) are also used to illustrate the characteristics of the proposed model. The proposed constitutive model provides a new dual 4-chain strategy for exploring rubber elasticity.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"175 ","pages":"Article 105122"},"PeriodicalIF":2.8,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143834016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Linear stability of Navier–Stokes–Voigt fluid under the influence of uniform magnetic field in a porous medium","authors":"C.M. Arjun,&nbsp;Praveena M.M.,&nbsp;Shashi Prabha Gogate S.,&nbsp;Bharathi M.C.","doi":"10.1016/j.ijnonlinmec.2025.105105","DOIUrl":"10.1016/j.ijnonlinmec.2025.105105","url":null,"abstract":"<div><div>We analyze the instability of plane Poiseuille flow for a viscoelastic Navier–Stokes–Voigt fluid influenced by a vertical magnetic field within a homogeneous porous medium. The viscoelastic fluid, confined between two parallel plates, is driven by a pressure gradient. To examine the effects of the Voigt parameter <span><math><mi>Λ</mi></math></span>, permeability <span><math><mi>Ω</mi></math></span>, and Hartmann number <span><math><mrow><mi>H</mi><mi>a</mi></mrow></math></span> on flow stability, we numerically solve the generalized eigenvalue problem using the Chebyshev spectral collocation method, which provides an accurate upper bound for stability. For the set of parameters, the plane Poiseuille flow of the Navier–Stokes–Voigt fluid stabilizes as <span><math><mi>Ω</mi></math></span> and <span><math><mrow><mi>H</mi><mi>a</mi></mrow></math></span> increase, preserving the Newtonian eigenspectrum within a specific range of <span><math><mi>Λ</mi></math></span>, <span><math><mi>Ω</mi></math></span>, and <span><math><mrow><mi>H</mi><mi>a</mi></mrow></math></span>. The eigenspectra display a characteristic <span><math><mi>Y</mi></math></span>-shaped structure with three distinct modes, depending on the phase speed. The instability consistently emerges in the wall mode for the physical parameters <span><math><mi>Λ</mi></math></span>, <span><math><mi>Ω</mi></math></span>, and <span><math><mrow><mi>H</mi><mi>a</mi></mrow></math></span>. The transition from laminar flow to turbulence is identified at a Reynolds number <span><math><mrow><mi>R</mi><mi>e</mi><mo>=</mo><mn>5772</mn><mo>.</mo><mn>22</mn></mrow></math></span> and a disturbance wavenumber <span><math><mrow><mi>a</mi><mo>=</mo><mn>1</mn><mo>.</mo><mn>02</mn></mrow></math></span> in the case of channel Poiseuille flow of a Newtonian fluid and this is termed as Tollmien–Schlichting instability. The neutral stability curves corresponding to different values of <span><math><mi>Λ</mi></math></span>, <span><math><mi>Ω</mi></math></span>, and <span><math><mrow><mi>H</mi><mi>a</mi></mrow></math></span> extend the Tollmien–Schlichting instability observed in Newtonian channel flow. Stability regions expand with increasing <span><math><mi>Λ</mi></math></span>, <span><math><mi>Ω</mi></math></span>, and <span><math><mrow><mi>H</mi><mi>a</mi></mrow></math></span>, as demonstrated by the neutral stability diagrams obtained for various associated parameters. Furthermore, the energy budget method is employed to validate our findings by quantifying the physical mechanisms driving instability. While Reynolds stress leads to negative energy production, viscous dissipation and viscoelastic contributions positively influence energy production, ultimately reducing the kinetic energy growth rate and enhancing stability.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"175 ","pages":"Article 105105"},"PeriodicalIF":2.8,"publicationDate":"2025-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143843160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unsteady one-dimensional flows of chemically reacting gas: Group analysis and solution of a strong explosion problem","authors":"Yu.N. Grigoriev ,&nbsp;E.I. Kaptsov ,&nbsp;S.V. Meleshko","doi":"10.1016/j.ijnonlinmec.2025.105100","DOIUrl":"10.1016/j.ijnonlinmec.2025.105100","url":null,"abstract":"<div><div>This work analyzes a system describing the motion of a two-component chemically reacting gas. We provide a complete group classification, enabling the identification of self-similar solutions to address the strong explosion problem. This approach allows for the examination of real Arrhenius-type chemical kinetics. Instead of solving a complex system of determining equations for admitted Lie groups, we employ an alternative method based on the system’s equivalence transformations. The strong explosion problem is studied, and, as in the classical case, the solution is reduced to integrating a system of ordinary differential equations in self-similar variables, which differ from the classical case. The results are illustrated with visual representations.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"175 ","pages":"Article 105100"},"PeriodicalIF":2.8,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143808112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 the camber angle of an aircraft radial tire: stress, contact, damage, and modal behaviors","authors":"Ziyao Ma ,&nbsp;Hanjing Lu ,&nbsp;Caishan Liu ,&nbsp;Xiaoting Rui","doi":"10.1016/j.ijnonlinmec.2025.105118","DOIUrl":"10.1016/j.ijnonlinmec.2025.105118","url":null,"abstract":"<div><div>During the landing process, there often exists a camber angle θ between the aircraft and the ground, complicating the tire-ground contact behavior and the consequential damage evolution. In this paper, a finite element analysis considering the cord-rubber composite structure of the aircraft radial tire, along with the hyperelasticity and Mullins effect of rubber is performed to investigate the effect of the camber angle θ on its stress distribution, the tire-ground contact behavior, the damage evolution, and the vibration characteristics. According to the stress analysis of the numerical results, under different θ, the tire shoulder is always the most vulnerable location where the stress concentrates the most and the Mullins damage indicator accumulates the most. The tire-ground contact behavior under different θ is analyzed and it is found that the vertical stiffness-displacement curves can be divided into three regimes due to the different involvement of the tire shoulder in the tire-ground contact process. The largest Mullins damage is first detected in the cross-section surface which is 30° from the middle of the contact region while as the load increases, the Mullins damage in the contact region increases rapidly and exceeds that in the 30° surface. Moreover, the vibration characteristics of the non-damaged tire and the damaged tire are extracted and compared. Different degrees of decrease in the natural frequencies are observed while no change is detected in modal shapes when Mullins damage is introduced. This paper reveals the importance of the tire shoulder in the tire structure design and the tire-ground contact process, and provides an insight into the damage monitoring technique of the aircraft radial tire.</div></div>","PeriodicalId":50303,"journal":{"name":"International Journal of Non-Linear Mechanics","volume":"175 ","pages":"Article 105118"},"PeriodicalIF":2.8,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143829796","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}