The clean fuels of ammonia and methanol are used to replace diesel in shipbuilding industry, but there exists corrosion risk for the engine parts in combustion products. The corrosion fatigue behavior of cylinder liners cast iron in simulated combustion product solutions of ammonia, methanol and diesel fuels were investigated. The corrosion rate and corrosion fatigue sensitivity in the three simulated

A new nonlinear fatigue cumulative damage model is proposed to address the challenge of insufficient accuracy in calculations stemming from nonlinear cumulative damage models that fail to account for strength degradation effects and interactions among multi-level loads. This model, an enhancement of the Aeran fatigue damage model, incorporates stress ratios to capture load interactions and includes

A novel Isogeometric topology optimization (ITO) method considering stress constraint and load uncertainties is proposed for the fiber reinforced composite structures. Firstly, with the density and fiber orientations at the control points of Non-Uniform Rational B-Splines (NURBS) defined as design variables while the magnitudes and direction angles of uncertain external loads described as interval

This paper develops a novel Hybrid Particle Element Method (HPEM) to model large deformation problems in solid mechanics, combining the strengths of both mesh-based and particle approaches. In the proposed method, the computational domain is discretized into two independent components: a set of finite elements and a set of particles. The finite elements serve as a temporary tool to compute the spatial

Continuum solid mechanics form the foundation of numerous theoretical studies and engineering applications. Distinguished from traditional mesh-based numerical solutions, the rapidly developing field of scientific machine learning, exemplified by methods such as physics-informed neural networks (PINNs), shows great promise for the study of forward and inverse problems in mechanics. However, accurately

The load-displacement softening response of quasi-brittle solids exhibits an unstable structural behavior, which is characterised by a negative slope in the post-peak regime. In severely brittle situations, the post-peak behaviour can show a virtual positive slope, the fracture propagation occurring unexpectedly with a catastrophic loss in the load-carrying capacity. In this case, if the displacement

High-temperature oxidation damage in C/SiC composite, alongside mechanical failure, has becoming a focal point of developing high performance motor components. However, most of existing models focus on only one field and thus can hardly to simulate a complete process. To address this, a thermodynamically consistent phase field model tailored specifically for C/SiC composites is proposed. This model

A complete understanding of the wrinkling of compressed films on curved substrates remains illusive due to the limitations of both analytical and current numerical methods. The difficulties arise from the fact that the energetically minimal distribution of deformation localizations is primarily influenced by the inherent nonlinearities and that the deformation patterns on curved surfaces are additionally

The phase field model (PFM) has emerged as a popular computational framework for analyzing and simulating complex fracture problems. Despite PFM's inherent capacity to model relatively complex fracture phenomena such as nucleation, branching, deflection, etc., the computational costs involved in the analysis are quite high. Hence, a multi-level adaptive mesh refinement framework is proposed for a unified

In this paper, a novel time-weighted residual methodology is developed in the two-field form of structural dynamics problems to enable generalized class of optimal zero-order overshooting Linear Multi-Step (LMS) algorithms by design. For the first time, we develop a novel time-weighted residual methodology in the two-field form of the second-order time-dependent systems, leading to the newly proposed

We propose a novel framework of generalised Petrov–Galerkin Dynamical Low Rank (DLR) Approximations in the context of random PDEs. It builds on the standard Dynamical Low Rank Approximations in their Dynamically Orthogonal formulation. It allows to seamlessly build-in many standard and well-studied stabilisation techniques that can be framed as either generalised Galerkin methods, or Petrov–Galerkin

The fatigue experiments for titanium alloy Ti60 under different uniaxial/multiaxial thermo-mechanical loading modes found that the combined action of high temperature and tensile stress can cause the debonding of the second phase strengthening particles between grain boundary, reducing the ability to resist deformation of Ti60, which leads to a decrease in the fatigue life of the material. In addition

Titanium alloy welded structures are often subjected to cyclic loading with composite waveform and variable amplitude during actual service, exacerbating the damage to the joints and leading to low fatigue life. Therefore, a three-stage heat treatment was adopted in this work to enhance the fatigue life of TC4 titanium alloy pulsed laser-arc hybrid welded joints, and its microstructure evolution and

The First-Order Reliability Method (FORM) is renowned for its high computational efficiency, but its accuracy declines when addressing the nNar Limit-State Function (LSF). The Second-Order Reliability Method (SORM) offers greater accuracy; however, its approximation formula can sometimes introduce errors. Additionally, SORM requires extra calculations involving the Hessian matrix, which can reduce

We propose a relatively simple and mesh-independent approach to model crack branching and merging using the Shifted Fracture Method (SFM), within the class of Shifted Boundary Methods. The proposed method achieves mesh independency by accurately accounting for the area of the fracture surface, in contrast to traditional element-deletion/node-release techniques. In the SFM, the true fracture is embedded

We consider the coupled Navier–Stokes/transport equations with nonlinear transmission conditions, which constitute one of the most common models utilized to simulate a reverse osmosis effect in water desalination processes when considering feed and permeate channels coupled through a semi-permeate membrane. The variational formulation consists of a set of equations where the velocities, the concentrations

We propose a randomized data-driven solver for multiscale mechanics problems which improves accuracy by escaping local minima and reducing dependency on metric parameters, while requiring minimal changes relative to non-randomized solvers. We additionally develop an adaptive data-generation scheme to enrich data sets in an effective manner. This enrichment is achieved by utilizing material tangent

High fidelity modeling of multiphysical systems is typically achieved using nonlinear coupled differential equations, often with multiscale model coefficients. These simulations are performed using finite-element methods with implicit time stepping. Within each time step, nonlinearities are numerically linearized using Newton-like iterative solvers, which increases the computational complexity. For

We study the numerical approximation of advection–diffusion equations with highly oscillatory coefficients and possibly dominant advection terms by means of the Multiscale Finite Element Method (MsFEM). The latter method is a now classical, finite element type method that performs a Galerkin approximation on a problem-dependent basis set, itself precomputed in an offline stage. The approach is implemented

The statistics obtained from turbulent flow simulations are generally uncertain due to finite time averaging. Most techniques available in the literature to accurately estimate these uncertainties typically only work in an offline mode, that is, they require access to all available samples of a time series at once. In addition to the impossibility of online monitoring of uncertainties during the course

This paper presents a finite element analysis of steady-state crack propagation in viscoelastic soft solids exhibiting Mullins softening. A cohesive-zone model is employed to simulate the localized processes at the tip of a Mode I crack in materials governed by viscoelastic behavior and damage-induced Mullins effects. The study numerically evaluates the intrinsic dissipation characteristics of typical

This paper introduces a digital twin solution for corner fatigue crack growth assessment. The digital twin comprises three core features: (1) diagnosis, (2) prognosis and (3) updating. The diagnosis arm performs remote crack size measurement via strain data collected from strategically identified locations. The prognosis component postulates the fatigue life across both linear-elastic and elasto-plastic

Soft-magnetorheological elastomers (s-MREs) are particulate composites made of a non-magnetic elastomeric matrix dispersed with micron-sized particles of a “soft-magnetic” material. The phenomenon of magnetostriction in specimens made from s-MREs is the change in their shape when they are subjected to an external magnetic field. Experiments in the literature show that for circular cylindrical specimens

In this paper, we extend the micromechanics-based phase-field model to simulate fatigue failure. The coupling of a micromechanics-based framework with the phase-field approach helps to differentiate between failure modes, by distinguishing between open and closed microcracks. This integrated framework links continuum field variables, such as plastic strain and damage variable, to micromechanical mechanisms

The work is devoted into investigating the multiaxial low cycle fatigue behavior and constitutive model of 316L under various strain amplitudes, strain ratios, and phase angles at 550 °C. Experimental results show that both axial and shear stress amplitudes present three stages of cyclic hardening, softening and fracture. Internal stress analysis reveals that initial cyclic hardening is influenced

The present paper studies fatigue crack growth (FCG) produced by a load pattern obtained numerically in a simulation of trains crossing a real bridge. It uses a model where the cyclic plastic deformation is assumed to be the main damage mechanism and that cumulative plastic strain at the crack tip is the driving parameter for FCG. The accumulation of damage was found to be very irregular along each

Continuum lattice grid structures which consist of joined elastic beams subject to flexural deformations are ubiquitous. In this work, we establish a theoretical framework of the topological dynamics of continuum lattice grid structures, and discover the topological edge and corner modes in these structures. We rigorously identify the infinitely many topological edge states within the bandgaps via

The ultra-high-strength engineering cementitious composites demonstrates pseudo strain hardening behavior when subjected to uniaxial tension, making it a promising material for enduring repeated or fatigue loads. Extensive research has been conducted on the quasi-static, dynamic, and fatigue behavior of this composites. However, due to the challenges of conducting direct tensile testing on concrete

This work considers a recently developed finite-deformation elastoplasticity theory that assumes distinct tensorial fields describing macro-plasticity and micro-plasticity, where the latter is determined by a higher-order balance equation with associated boundary conditions. Specifically, micro-plasticity evolves according to a contribution to the Helmholtz free-energy density that depends on a Nye–Kröner-like

The mechanical properties of fractured rock mass have an important influence on the safety and stability of underground engineering. Grouting is a common way to reinforce fractured rock mass. The uniaxial compression tests of red sandstone specimens with different prefabricated crack inclination angles before and after grouting were carried out. Based on the load-deformation data and synchronous image

Concrete is prone to damage under explosive loads, which can cause a large number of casualties and property losses. The concrete fragmentation process during explosion is transient and dynamic, and the experimental measurement of such events is difficult and risky to conduct, and the intermediate explosion process is difficult to observe in the experimental tests. Therefore, the numerical simulation

This paper proposes a new infill criterion for the optimization of expensive black-box design problems. The method complements the classical Efficient Global Optimization algorithm by considering the distribution of improvement instead of merely the expectation. During the optimization process, we maximize a penalized expected improvement acquisition function from a specially collected infill candidate

Understanding uncertainty is critical, especially when data are sparse and variations are large. Bayesian neural networks offer a powerful strategy to build predictable models from sparse data, and inherently quantify both, aleatoric uncertainties of the data and epistemic uncertainties of the model. Yet, classical Bayesian neural networks ignore the fundamental laws of physics, they are non-interpretable

The advantages of data science have inspired the development of data-driven approaches for solving constitutive modeling problems, which have become a new research focus in engineering mechanics. These approaches help fully utilize the information inherent in the data, bypassing the traditional modeling processes.

This paper presents a convolution tensor decomposition based model reduction method for solving the Allen–Cahn equation. The Allen–Cahn equation is usually used to characterize phase separation or the motion of anti-phase boundaries in materials. Its solution is time-consuming when high-resolution meshes and large time scale integration are involved. To resolve these issues, the convolution tensor

In this paper, we introduce a novel, data-driven approach for solving high-dimensional Bayesian inverse problems based on partial differential equations (PDEs), called Weak Neural Variational Inference (WNVI). The method complements real measurements with virtual observations derived from the physical model. In particular, weighted residuals are employed as probes to the governing PDE in order to formulate

Non-probabilistic convex models are powerful tools for structural model updating with uncertain‑but-bounded parameters. However, existing non-probabilistic model updating (NPMU) methods often struggle with detecting parameter correlation due to limited prior information. Worth still, the unique core steps of NPMU, involving nested inner layer forward uncertainty propagation and outer layer inverse

Multiaxial fatigue life prediction models rely on intrinsic parameters that provide the balance between arbitrary and reference stress/strain conditions. However, this balance may be compromised due to evolving damage mechanisms, causing initially determined model parameters to deviate from actual values, resulting in life prediction errors. Despite the significant impact of fatigue model parameters

Time-dependent deformation and damage in viscoelastic materials exhibit distinct characteristics compared to purely brittle or ductile materials, especially under large deformations. These behaviours become even more complex in the presence of pre-cracks. To model this process, we propose an improved non-ordinary state-based peridynamics (NOSB-PD) with implicit adaptive time-stepping (IATS). The proposed

An experiment was conducted to evaluate the creep-thermal fatigue (CTF) behavior of thin-walled structures with holes. To achieve this, a high-temperature hold phase was added in the testing. The crack propagation of CTF is driven by the combined effects of creep, thermal fatigue, and oxidation. Therefore, a creep-thermal fatigue-oxidation phase field model was developed to simulate CTF behavior. The

The fatigue-induced fracture failure of the aircraft canopy occurred in the poly(methyl methacrylate) (PMMA) layer laminated on polycarbonate (PC) during flight. For more than 24 years, the aircraft had been operated at high altitudes and supersonic flight. To identify the root cause and the mechanism for the formation of the fracture, the fracture surfaces were investigated. The fracture morphologies

The computational cost associated with structural reliability analysis increases substantially when dealing with multiple response metrics and high-dimensional input spaces. To address this challenge, an innovative global prediction framework is proposed which leverages multi-output Gaussian process (MOGP) modeling. This framework reduces the computational burden for high-dimensional, multi-response

Uncertainty quantification (UQ) and inference involving a large number of parameters are valuable tools for problems associated with heterogeneous and non-stationary behaviors. The difficulty with these problems is exacerbated when these parameters are statistically dependent requiring statistical characterization over joint measures. Probabilistic modeling methodologies stand as effective tools in

Pulmonary capillary perfusion and gas exchange are physiological processes that take place at the alveolar level and that are fundamental to sustaining life. Present-day computational simulations of these phenomena are based on low-dimensional mathematical models solved in idealized alveolar geometries, where the chemical reactions between O2-CO2 and hemoglobin are simplified. While providing general

Fatigue crack growth (FCG) tests were conducted on compact tension specimens made of a Ni-based superalloy to investigate the near-threshold FCG behaviors using both the stepped load reduction method (LRM) and the constant-amplitude loading method (CALM) at three stress ratios (R = 0.05, 0.5 and 0.7) under ambient condition. It is found that after the FCG threshold being approached by the LRM, a remarkable

In order to isolate the influence of ply orientation on the mode I fatigue delamination propagation behavior of carbon fiber reinforced composite laminates, multidirectional laminates with the same overall stiffness are designed while three different interfaces (0//0, 45//45, and 90//90), which can avoid the coupling effect of remote plies. Test results show that the fatigue delamination behavior is

A three-layered experimental thermal and environmental barrier coating (TEBC) was deposited using air plasma spraying technology on cylindrical specimens of nickel-based superalloy MAR-M247. TEBC consists of mullite (Al6Si2O13) and hexacelsian (BaAl2Si2O8) upper layer, Y2O3 stabilised ZrO2 interlayer and CoNiCrAlY bond coat deposited on the grit-blasted surface of MAR-M247. The cyclic plastic response

A systematic understanding of the toughening and self-healing mechanisms of artificial soft tissues is crucial for advancing their robust application in biomedical engineering. However, current models predominantly possess a phenomenological nature, often devoid of micromechanical intricacies and quantitative correlation between microstructure damage and macroscopic energy dissipation. To bridge this

This paper presents an innovative methodology that seamlessly integrates the peridynamic method with advanced deep learning techniques, specifically utilizing the Gated Recurrent Unit (GRU) neural network. This integration results in the development of a highly accurate and efficient model for predicting fatigue cracking and life. This model can effectively forecast the fatigue crack patterns and fatigue

The aim of the present work is to design, analyze theoretically, and test numerically, a generalized Dryja–Smith–Widlund (GDSW) preconditioner for composite Discontinuous Galerkin discretizations of multicompartment parabolic reaction–diffusion equations, where the solution can exhibit natural discontinuities across the domain. We prove that the resulting preconditioned operator for the solution of

Modeling damage and failure behaviors of hyperelastic composites under large deformations is pivotal for advancing the design of cutting-edge elastomers used in biomedical engineering and soft robotics. However, existing methods struggle with capturing the non-linearities and singularities in the displacement field under such conditions. To address these difficulties, we propose a novel bond-based

In this paper, we present a Bayesian framework for the identification of the parameters of nonlinear constitutive material laws using full-field displacement measurements. The concept of force-based Finite Element Model Updating (FEMU-F) is employed, which relies on the availability of measurable quantities such as displacements and external forces. The proposed approach particularly unfolds the advantage

In engineering applications, surface modifications of materials can greatly influence the lifetime of parts and structures. For instance, laser melt injection (LMI) of ceramic particles into a metallic substrate can greatly improve abrasive resistance. The LMI process is challenging to model due to the rapid temperature changes, which induce high mechanical stresses. Ultimately, this leads to plastification

We propose a novel variational framework to regularize softening plasticity problems. Specifically, we modify the plastic dissipation potential term by adding a contribution depending on the cumulative plastic strain-rate gradient. We formulate the evolution of the so-obtained strain-rate gradient plasticity model with an incremental variational principle. The time-discretized evolution equations are

An efficient SGBEM–FEM framework for predicting transient hydrocarbon production by coupling transient Darcy flow and channel flow is proposed, which extends the steady state analysis framework developed in Hu and Mear (2022). The governing equation of transient Darcy flow in the matrix is formulated by an integral equation method, and that of channel flow in the fracture is cast in a weak form suitable

Stress and material deformation field predictions are among the most important tasks in computational mechanics. These predictions are typically made by solving the governing equations of continuum mechanics using finite element analysis, which can become computationally prohibitive considering complex microstructures and material behaviors. Machine learning (ML) methods offer potentially cost effective

Exploring the long-term performance of welded details in composite trapezoidal corrugated web (TCW) girders is a significant focus for the service life of these structures exposed to atmospheric environment and traffic flow. The majority of the present studies have been conducted without accounting for thermal stresses induced by temperature differences and accurately reflecting internal force transfers

In fields where predictions may have vital consequences, uncertainty quantification (UQ) plays a crucial role, as it enables more accurate forecasts and mitigates the potential risks associated with decision-making. However, performing uncertainty quantification in real-world scenarios necessitates multiple evaluations of complex computational models, which can be both costly and time-consuming. To

Nickel-based single-crystal (SC) superalloys exhibited excellent exceptional mechanical properties at high temperatures due to the elimination of internal grain boundaries, contributed a strong orientation-dependent material response. The anisotropy of SC superalloys was modeled viscoplastically from a macroscopic viewpoint based on the Kelvin decomposition theory [1] which was a decomposition of the

We present a novel high order semi-implicit hybrid finite volume/virtual element numerical scheme for the solution of compressible flows on Voronoi tessellations. The method relies on the operator splitting of the compressible Navier–Stokes equations into three sub-systems: a convective sub-system solved explicitly using a finite volume (FV) scheme, and the viscous and pressure sub-systems which are