Mechanics Research Communications最新文献_第8页

Feasible and robust optimisation of cable forces in suspended bridges: A two-stage metaheuristic approach 悬索桥缆索力的可行和稳健优化：两阶段元启发式方法

IF 2.3 4区工程技术 Q3 MECHANICS

Mechanics Research Communications

Pub Date : 2025-10-25 DOI: 10.1016/j.mechrescom.2025.104554

Ida Mascolo, Sina Sarfarazi, Mariano Modano

The adjustment of cable pretension in suspended-deck bridges is a critical inverse design problem, where feasibility and robustness are as important as accuracy. Conventional methods such as finite-element (FE) re-analysis or the Influence Matrix Method (IMM) provide algebraic solutions but often produce oscillatory or infeasible patterns once field constraints are applied. This study introduces a two-stage framework that integrates stiffness-based sensitivity analysis with constrained metaheuristic optimisation. In stage-1 a reduced-order banded influence operator is introduced, which reflects how changes at the cable scale propagate over a limited range before combining into the global deck deformation. The effective bandwidth is tied to hanger spacing and deck stiffness, giving a natural connection between actuator-level inputs and system-level response. In Stage-2, cable adjustments are determined through multi-objective optimisation that balances target matching, smoothness, symmetry, and bounded jack capacities. Two population-based strategies, Particle Swarm Optimisation (PSO) and Grey Wolf Optimisation (GWO), are benchmarked against convex regularization baselines on the Gravina Bridge (Italy). Both metaheuristics deliver symmetric, bounded, and contiguous force patterns that reproduce the target profile while remaining compatible with staged field operations. Robustness analysis under structured perturbations confirms near 14% reductions in mean and tail-risk errors relative to convex solutions, while reproducibility is ensured through constrained search and convex polishing. The results demonstrate that the framework provides accurate and constructible re-tensioning strategies, clarifying how scale interactions in cable–deck systems can be exploited for reliable design and maintenance.

悬索式桥面桥梁索张力调整是一个关键的反设计问题，其可行性和鲁棒性与准确性同等重要。传统的方法，如有限元（FE）再分析或影响矩阵法（IMM）提供了代数解，但一旦应用了场约束，通常会产生振荡或不可行的模式。本研究引入了一个两阶段框架，将基于刚度的灵敏度分析与约束的元启发式优化相结合。在阶段1中，引入了一个降阶带状影响算子，它反映了电缆尺度的变化如何在有限范围内传播，然后结合到整体甲板变形中。有效带宽与悬挂器间距和甲板刚度有关，从而在执行器级输入和系统级响应之间建立了自然联系。在第二阶段，通过多目标优化来确定电缆调整，平衡目标匹配、平滑度、对称性和有限千斤顶容量。两种基于种群的策略，粒子群优化（PSO）和灰狼优化（GWO），在Gravina桥（意大利）的凸正则化基线上进行了基准测试。这两种元启发式方法都提供对称、有界和连续的力模式，再现目标剖面，同时与分阶段的现场操作保持兼容。结构化扰动下的鲁棒性分析证实，相对于凸解，平均和尾部风险误差减少了近14%，同时通过约束搜索和凸抛光确保了再现性。结果表明，该框架提供了准确和可构建的再张拉策略，阐明了如何利用索-甲板系统中的尺度相互作用进行可靠的设计和维护。

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引用次数: 0

Nonlocal elastic plate problems via iterative method 基于迭代法的非局部弹性板问题

IF 2.3 4区工程技术 Q3 MECHANICS

Mechanics Research Communications

Pub Date : 2025-10-21 DOI: 10.1016/j.mechrescom.2025.104538

Andrea Caporale , Marzia Sara Vaccaro , Raffaele Barretta , Raimondo Luciano

Elastostatics of nanoplates is addressed via an effective iterative procedure. An integral theory of elasticity is exploited to capture size effects in thin plates. The governing nonlocal elastic problem is represented by an integro-differential formulation, whose resolution is particularly demanding. Moreover, extending solution methodologies to general plate geometries and arbitrary boundary and loading conditions is a complex issue to address. To overcome these limitations, an effective iterative method is proposed. Such an algorithm relies solely on the solution of standard local elastostatic problems. Indeed, according to the iterative scheme, the nonlocal solution is obtained by solving a sequence of local problems. The presented methodology accommodates arbitrary nanoplate geometries and general kernels of the constitutive integral law, ensuring broad applicability and making it suitable for modeling a wide spectrum of nanoengineered systems.

通过有效的迭代过程求解了纳米板的弹性静力学问题。利用弹性的整体理论来捕捉薄板的尺寸效应。控制非局部弹性问题用积分-微分公式表示，其求解要求特别高。此外，将求解方法扩展到一般板几何形状和任意边界和加载条件是一个复杂的问题。为了克服这些局限性，提出了一种有效的迭代方法。该算法仅依赖于标准局部弹性静力问题的解。实际上，根据迭代格式，非局部解是通过求解一系列局部问题得到的。所提出的方法适用于任意纳米板几何形状和本构积分定律的一般内核，确保了广泛的适用性，并使其适合于建模广泛的纳米工程系统。

引用次数: 0

An investigation of thermoelastic behavior in periodic and functionally graded multilayered composite structures using tolerance modeling and finite element methods 利用公差建模和有限元方法研究周期性和功能梯度多层复合材料结构的热弹性行为

IF 2.3 4区工程技术 Q3 MECHANICS

Mechanics Research Communications

Pub Date : 2025-10-20 DOI: 10.1016/j.mechrescom.2025.104546

Olga Szlachetka , Ivan Giorgio

In response to the increasing demand for accurate yet computationally efficient methods for analyzing modern composites under thermal loading, this study introduces a thermoelastic model for multicomponent, multilayer step-wise functionally graded materials (FGMs), based on the tolerance modeling approach. For the first time, the tolerance modeling method has been extended to the thermoelasticity equations of FGM structures comprising more than two components, which marks a clear departure from earlier studies mostly limited to two-component materials or, if for multi-component, then only for periodic structures. This extension enables a significantly more realistic representation of modern layered composites. Numerical verification of the model was performed using Mathematica and COMSOL Multiphysics, enabling assessment of both accuracy and predictive capability. Deviations from COMSOL-based reference results did not exceed 7 % for both periodic and step-wise FGM structures, confirming the high reliability of the approach. Unlike existing methods, which are often either oversimplified or extremely computationally demanding, the developed model provides a realistic description of structural behavior while requiring considerably less computational effort than classical finite element methods (FEM). The analysis has direct practical relevance to the design of components exposed to high thermal gradients, such as thermal shields in aerospace applications, layered partitions in energy-efficient buildings, and electronic device components. Accurate prediction of displacement and thermal stress distributions facilitates optimization of geometry and material layout, reducing stress concentrations and minimizing damage risk. A comparative analysis of analytical and numerical results under identical boundary conditions and geometries confirms that the tolerance model successfully captures the behavior of FGM structures while keeping computational costs low. The conclusions further indicate that ordered, symmetric layering reduces deformation, whereas asymmetry and abrupt material transitions lead to localized stress concentrations. The novel methodology not only broadens existing modeling capabilities but is also flexible and can be adapted to a wide spectrum of modern layered structures, enhancing its potential for practical engineering applications.

为了满足日益增长的对精确且计算效率高的现代复合材料热载荷分析方法的需求，本研究引入了基于公差建模方法的多组分多层阶梯功能梯度材料（fgm）的热弹性模型。这是第一次将公差建模方法扩展到包含两个以上组分的FGM结构的热弹性方程中，这标志着与以往的研究明显不同，这些研究大多局限于双组分材料，如果是多组分，则仅适用于周期结构。这个扩展使现代分层复合材料的显着更逼真的表示。使用Mathematica和COMSOL Multiphysics对模型进行了数值验证，从而能够评估模型的准确性和预测能力。对于周期性和渐进式FGM结构，与基于comsol的参考结果的偏差不超过7%，证实了该方法的高可靠性。与现有的方法不同，这些方法通常要么过于简化，要么对计算量要求极高，所开发的模型提供了对结构行为的真实描述，而所需的计算量比经典有限元方法（FEM）要少得多。该分析与暴露在高热梯度下的组件的设计直接实际相关，例如航空航天应用中的热屏蔽，节能建筑中的分层隔板和电子设备组件。准确预测位移和热应力分布有助于优化几何形状和材料布局，减少应力集中，最大限度地降低损伤风险。对相同边界条件和几何形状下的解析和数值结果进行了对比分析，证实了该公差模型成功地捕获了FGM结构的行为，同时保持了较低的计算成本。结论进一步表明，有序、对称的分层减少了变形，而不对称和突然的材料转变导致局部应力集中。这种新颖的方法不仅拓宽了现有的建模能力，而且还具有灵活性，可以适应广泛的现代分层结构，增强了其实际工程应用的潜力。

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引用次数: 0

On the stability of imperfect Von Mises arches 不完全Von Mises拱的稳定性

IF 2.3 4区工程技术 Q3 MECHANICS

Mechanics Research Communications

Pub Date : 2025-10-20 DOI: 10.1016/j.mechrescom.2025.104542

Antonio Capsoni

This communication aims to provide further insight into the interaction between the classical limit point instability (“snap-through”) of a Von Mises arch and the Eulerian buckling of its constituent rods. The theoretical model incorporates the effects of symmetric geometric imperfections in the rods, as well as the reduction in axial stiffness resulting from second-order effects. The analysis is developed on a theoretical basis to elucidate the influence of key governing parameters—namely, arch shallowness, rod slenderness, and imperfection magnitude. Numerical simulations are performed to validate and illustrate the proposed formulation.

本文旨在进一步深入了解冯·米塞斯拱的经典极限点不稳定性（“穿透”）与其组成杆的欧拉屈曲之间的相互作用。该理论模型结合了杆的对称几何缺陷的影响，以及二阶效应导致的轴向刚度降低。该分析是在理论基础上进行的，旨在阐明拱浅度、杆长细度和缺陷大小等关键控制参数的影响。数值模拟验证和说明了所提出的公式。

引用次数: 0

Assessment of higher-order shear and normal deformation theory models for the thermoelastic analyses of functionally graded cylindrical shells 功能梯度圆柱壳热弹性分析的高阶剪切和法向变形理论模型评估

IF 2.3 4区工程技术 Q3 MECHANICS

Mechanics Research Communications

Pub Date : 2025-10-19 DOI: 10.1016/j.mechrescom.2025.104545

Ngoc Doan Tran

This article presents a comprehensive assessment of displacement-based higher-order shear and normal deformation theories (HOSNTs) for the thermoelastic analysis of functionally graded (FG) cylindrical shells. For the first time, HOSNT models of various orders ranging from 3 to 7 are employed in conjunction with a one-step transverse stress recovery technique to investigate the through-thickness distribution of stress components and von Mises stress, particularly at the middle position and near-boundary zone. The governing equations and representative boundary conditions are derived based on the principle of virtual work, and the solution is obtained analytically using simple trigonometric series in combination with the Laplace transform method. The effective properties of the FG material are modeled as a power-law function of the radial coordinate. Comparisons are made between the obtained results and those available in the literature to validate the models. Parametric studies are conducted to assess the influence of shell relative thickness, boundary conditions, material non-homogeneity index, and combined thermomechanical loading on the through-thickness distributions of non-dimensional stresses. Based on both theoretical and numerical results, recommendations are proposed for the effective applicability ranges of different HOSNT models in the analysis of FG cylindrical shells subjected to thermomechanical loads.

本文提出了基于位移的高阶剪切和法向变形理论（hosnt）的综合评估，用于功能梯度（FG）圆柱壳的热弹性分析。首次将3 ~ 7阶的HOSNT模型与一步横向应力恢复技术相结合，研究了应力分量和von Mises应力的全厚度分布，特别是在中间位置和近边界区。根据虚功原理推导了控制方程和具有代表性的边界条件，并结合拉普拉斯变换方法，采用简单三角级数法解析求解。FG材料的有效性能以径向坐标的幂律函数建模。将所得结果与文献中可用的结果进行比较，以验证模型的有效性。通过参数化研究，评估了壳体相对厚度、边界条件、材料非均匀性指数和复合热-机械载荷对无量纲应力贯穿厚度分布的影响。根据理论和数值结果，提出了不同HOSNT模型在热载荷作用下FG圆柱壳分析中的有效适用范围。

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引用次数: 0

Prediction of the texture evolution during forming of an 6016 aluminum alloy based on VPSC and macroscopic anisotropic model 基于VPSC和宏观各向异性模型的6016铝合金成形织构演化预测

IF 2.3 4区工程技术 Q3 MECHANICS

Mechanics Research Communications

Pub Date : 2025-10-17 DOI: 10.1016/j.mechrescom.2025.104541

Rahul Rakshit, Benoit Revil-Baudard

In this study, we present a computationally efficient way to predict the deformation behaviour and texture evolution during mechanical tests and sheet metal forming operations. A two-pronged approach is developed. An orthotropic yield criterion that represents with accuracy the engineering level material’s anisotropy and ensures computational efficiency is used to simulate the deep drawing process. The finite-element (FE) predicted strains are further used to inform the visco-plastic self-consistent (VPSC) crystal plasticity model to predict the texture in different regions of the fully drawn cylindrical cup. This approach is illustrated for a strongly anisotropic aluminium alloy. For this purpose, the available data from uniaxial tensile tests were utilised to determine the anisotropy coefficients associated with the orthotropic model and the crystallographic slip hardening parameters for the VPSC model, respectively. The capabilities of the VPSC model are first illustrated by comparing the experimental and predicted stress-strain response for various orientations as well as the anisotropy in the Lankford coefficients and post-test textures. Furthermore, using VPSC the evolution of plastic anisotropy during deep drawing process was also systematically studied and comparisons with available textures from various locations on the cup are reported. The good agreement with data show that this approach leads to accurate results while preserving computational efficiency.

在这项研究中，我们提出了一种计算有效的方法来预测机械测试和钣金成形过程中的变形行为和织构演变。制定了双管齐下的办法。采用正交各向异性屈服准则，准确地表示工程级材料的各向异性，并保证计算效率来模拟拉深过程。利用有限元（FE）预测应变，建立粘塑性自洽（VPSC）晶体塑性模型，对全拉伸圆柱杯不同区域的织构进行预测。这种方法在强各向异性铝合金中得到了说明。为此，利用单轴拉伸试验的可用数据分别确定与正交各向异性模型相关的各向异性系数和VPSC模型的晶体滑移硬化参数。VPSC模型的能力首先通过比较不同取向的实验和预测应力应变响应以及兰克福德系数和测试后纹理的各向异性来说明。此外，利用VPSC系统地研究了拉深过程中塑性各向异性的演变，并与杯子上不同位置的可用纹理进行了比较。结果表明，该方法在保证计算效率的前提下，得到了准确的结果。

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引用次数: 0

Shape optimization of Hencky-type Reddy columns against buckling using genetic algorithms and artificial neural networks 基于遗传算法和人工神经网络的henky型Reddy柱抗屈曲形状优化

IF 2.3 4区工程技术 Q3 MECHANICS

Mechanics Research Communications

Pub Date : 2025-10-01 DOI: 10.1016/j.mechrescom.2025.104540

Ali Forooghi , Davide Pellecchia , Eugenio Ruocco

The current investigation proposes a computationally efficient framework for optimizing the buckling performance of non-uniform beams by means of an enhanced Hencky bar-chain model (HBM) combined with Reddy’s higher-order beam theory. The model effectively captures shear deformation, making it appropriate for analyzing thick beams where classical models may fall short. To lessen the high computational cost typically associated with iterative buckling analyses, a surrogate model is developed utilizing artificial neural networks (ANNs), trained to forecast critical buckling loads with high precision. The trained ANN is then integrated into a genetic algorithm framework for both single- and multi-objective optimization, which leads to considerable acceleration in the design process. The approach is tested across different boundary conditions, including simply supported, clamped–free, clamped–sliding, and clamped–clamped cases. The obtained results demonstrate that the ANN-based predictions closely match those acquired from high-fidelity eigenvalue solvers while decreasing computational time. In general, the integration of the HBM with machine learning-assisted evolutionary algorithms leads to a dependable approach for the shape optimization of beams under buckling constraints. Such a framework provides precise outcomes with decreased computational effort and can be considered a solid foundation for future developments in structural stability.

本研究提出了一种计算效率高的框架，用于优化非均匀梁的屈曲性能，该框架采用增强型Hencky杆链模型（HBM）和Reddy的高阶梁理论相结合。该模型有效地捕获了剪切变形，使其适用于分析经典模型可能不足的厚梁。为了减少迭代屈曲分析的高计算成本，利用人工神经网络（ann）开发了一个替代模型，该模型经过训练，可以高精度地预测临界屈曲载荷。然后将训练好的人工神经网络集成到遗传算法框架中进行单目标和多目标优化，从而大大加快了设计过程。该方法在不同的边界条件下进行了测试，包括简支撑、无夹紧、夹紧滑动和夹紧夹紧的情况。结果表明，基于人工神经网络的预测与高保真特征值求解器的预测结果非常接近，同时减少了计算时间。一般来说，HBM与机器学习辅助进化算法的集成为屈曲约束下梁的形状优化提供了可靠的方法。这样的框架以较少的计算工作量提供了精确的结果，可以被认为是结构稳定性未来发展的坚实基础。

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引用次数: 0

Energy equivalence-based homogenized micropolar model for 2D high valency architected materials: Periodic, semi-periodic, and aperiodic 基于能量当量的二维高价结构材料均质微极性模型：周期性、半周期性和非周期性

IF 2.3 4区工程技术 Q3 MECHANICS

Mechanics Research Communications

Pub Date : 2025-10-01 DOI: 10.1016/j.mechrescom.2025.104530

Vardhil Kirtikumar Mehta, Arun R. Srinivasa, J.N. Reddy

This study aims to develop a unified method for energy-based homogenization of different classes of architected materials. Unlike the majority of the currently available homogenized models, the proposed model is capable of modeling not only periodic microstructures but also graded, distorted, and random mesostructures. The notion of a non-repeating characteristic cell is introduced to quantify both the geometry and topology of the mesostructures, which helps categorize them into three main classes: periodic, semi-periodic, and aperiodic. The discrete body of an architected material is homogenized at the scale of the characteristic cell by invoking local energy equivalence, resulting in a micropolar continuum at the macroscale with spatially varying material properties. The homogenization process involves obtaining the strain energy of the discrete body (with high valency) using a frame model, performing a homogenization approximation via a physically intuitive limiting process, and finally, obtaining the constitutive relation for the continuum in its unified general form. The finite element model of the micropolar continuum is developed and implemented in a computer program for numerical solutions. First, the periodic and semi-periodic variants of the rectangular mesostructure are analyzed. The efficacy of the homogenized model is tested by comparing the results of a boundary value problem with those of the discrete frame model. Next, for aperiodic mesostructures, a slightly different approach is introduced, involving proxy characteristic cells that significantly reduce the computational complexity of the model. The homogenized model is verified against a sample of five instances of aperiodic mesostructure under a set of boundary value problems. The study also demonstrates that, with fairly good accuracy, the homogenized model incurs an impressive reduction in computational expense compared to the discrete frame model.

本研究旨在开发一种统一的方法，以能量为基础的均匀化不同类别的建筑材料。与目前大多数可用的均质化模型不同，该模型不仅能够模拟周期性微观结构，还能够模拟渐变、扭曲和随机的细观结构。引入了非重复特征单元的概念来量化介观结构的几何形状和拓扑结构，这有助于将介观结构分为三大类：周期、半周期和非周期。通过调用局部能量等效，结构材料的离散体在特征单元尺度上均匀化，从而在宏观尺度上形成具有空间变化的材料特性的微极性连续体。均匀化过程包括使用框架模型获得离散体（高价）的应变能，通过物理直观的极限过程进行均匀化近似，最后获得连续统统一一般形式的本构关系。建立了微极连续体的有限元模型，并在计算机程序中进行了数值求解。首先，分析了矩形细观结构的周期和半周期变分。通过将边界值问题的结果与离散框架模型的结果进行比较，验证了均匀化模型的有效性。接下来，对于非周期介结构，引入了一种稍微不同的方法，涉及代理特征细胞，显着降低了模型的计算复杂性。在一组边值问题下，用5个非周期细观结构实例对均匀化模型进行了验证。该研究还表明，与离散框架模型相比，均匀化模型的计算费用显著减少，精度相当高。

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引用次数: 0

Bishop nanorods with stress-driven nonlocal elasticity and arbitrary boundary conditions 具有应力驱动非局部弹性和任意边界条件的Bishop纳米棒

IF 2.3 4区工程技术 Q3 MECHANICS

Mechanics Research Communications

Pub Date : 2025-10-01 DOI: 10.1016/j.mechrescom.2025.104533

Francesco Paolo Pinnola , Raimondo Luciano , Francesco Marotti de Sciarra

One-dimensional structural elements, such as thick rods, are essential in the development of nanoscale electromechanical systems. Their design and mechanical behavior at small scales can be effectively described using nonlocal continuum mechanics, which captures size-dependent effects and long-range interactions while reducing computational costs compared to atomistic methods. This study analyzes small-scale thick rods with realistic boundary conditions using Bishop’s model, incorporating a nonlocal integral constitutive relation. Usually, the nonlocal relation is derived from Eringen’s integral model, in which the nonlocal stress at a point depends on the entire strain field through a Fredholm-type convolution integral. However, this strain-driven formulation may lead to inconsistencies when applied to bounded domains. To address these issues, a stress-driven nonlocal integral formulation is adopted, providing a well-posed mechanical model that admits analytical solutions. A parametric study is conducted to evaluate the influence of nonlocal effects under various boundary conditions. Theoretical and numerical results contribute to a better understanding of the mechanical behavior of nanorods and offer valuable insights for the design of small-scale components.

一维结构元件，如粗杆，在纳米级机电系统的发展中是必不可少的。它们在小尺度上的设计和力学行为可以使用非局部连续介质力学有效地描述，与原子方法相比，它可以捕获尺寸依赖效应和远程相互作用，同时降低计算成本。本文采用Bishop模型，结合非局部积分本构关系，对具有实际边界条件的小尺度粗杆进行了分析。通常，非局部关系是由Eringen的积分模型推导出来的，其中一点的非局部应力通过fredholm型卷积积分依赖于整个应变场。然而，当应用于有界域时，这种应变驱动的公式可能导致不一致。为了解决这些问题，采用了应力驱动的非局部积分公式，提供了一个允许解析解的适定力学模型。对不同边界条件下非局部效应的影响进行了参数化研究。理论和数值结果有助于更好地理解纳米棒的力学行为，并为小型部件的设计提供有价值的见解。

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引用次数: 0

Effects of magnetically highly and weakly conducting interfaces on flexomagnetic waveguide layered system 高导和弱导界面对柔性磁波导层状系统的影响

IF 2.3 4区工程技术 Q3 MECHANICS

Mechanics Research Communications

Pub Date : 2025-10-01 DOI: 10.1016/j.mechrescom.2025.104534

Richa Kumari , Santosh Kapuria , Santan Kumar

This work sheds light on the different modes of Love-type wave propagation in a flexomagnetic smart composite stratified structure involving imperfect interface. To be specific, the structure incorporates a piezomagnetic layer with flexomagnetic and micro-inertia effects, which is bonded imperfectly to a piezomagnetic semi-space. By means of variable separable approach, dispersion equations are determined for imperfect interfaces, viz. mechanically compliant and magnetically weakly and mechanically compliant and magnetically highly conducting interfaces, for both magnetically open and magnetically short conditions. The established dispersion equations, as special case, concur well with the classical result existing in the literature. Numerical simulation is performed to illustrate the effects of micro-inertia length-scale parameter, flexomagnetic constant, imperfectness parameters, wave number and thickness of layer on distinct modes of Love-type wave velocity for both the magnetic conditions. The numerical results manifest the substantial impact of mechanically compliant and magnetically highly conducting imperfect interface on Love-type wave as compared to mechanically compliant and magnetically weakly conducting imperfect interface. The results of the study may be applicable in designing magnetic systems such as actuators, sensors and energy harvesting devices.

本研究揭示了含不完美界面的柔性磁智能复合材料层状结构中love型波的不同传播模式。具体而言，该结构包含具有挠磁和微惯性效应的压磁层，该层与压磁半空间不完美结合。采用可变可分方法，确定了磁开和磁短条件下的不完全界面（即机械柔顺和磁性弱、机械柔顺和磁性强的界面）的色散方程。所建立的色散方程作为特例，与文献中的经典结果吻合较好。通过数值模拟分析了微惯性长度尺度参数、柔磁常数、缺陷参数、波数和层厚对两种磁性条件下love型波速不同模态的影响。数值结果表明，与机械柔顺和弱导磁不完美界面相比，机械柔顺和高导磁不完美界面对love型波的影响更大。研究结果可应用于磁致动器、传感器和能量收集装置等磁性系统的设计。

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引用次数: 0