European Journal of Mechanics A-Solids最新文献_第8页

A novel negative stiffness inertial amplifier absorber for mitigating bridge vibrations under moving loads 一种新型的负刚度惯性放大器吸收器，用于减轻移动荷载下桥梁的振动

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-26 DOI: 10.1016/j.euromechsol.2025.105960

Susmita Panda , Arnab Banerjee , Bappaditya Manna

The heavier axle moving at high speed over critical locations such as road or rail crossings may induce excessive vibrations, detrimental to structure and passenger comfort. To address this, vibration absorbers can be tuned to effectively reduce the vibrations caused by moving wheel loads. Traditional tuned mass systems and inerter-based devices often face limitations due to requirement of heavy mass and moving components. To overcome these challenges, this paper introduces a theoretical formulation for novel negative-stiffness inertial amplifier-based vibration absorber system (NSIABVA) to mitigate train-induced vibrations. To analyze a simply-supported bridge’s dynamics, an Euler–Bernoulli beam under successive loads is modeled using a non-dimensional framework. Additionally, optimization of NSIABVA using a genetic algorithm is proposed and shows strong agreement with Den Hartog’s classical theory for tuned mass systems, validating its accuracy. The proposed NSIABVA configuration offers superior vibration mitigation driven by significant effective mass and stiffness amplification for different values of frequency and mass tuning ratio. While conventional IABVAs reduce displacement by 50%–70%, the NSIABVA achieves a 70%–90% reduction. Unlike IABVA, which mainly enhances energy dissipation, NSIABVA also improves damping and structural load-bearing capacity. Additionally, statistical analysis identifies optimal absorber design parameters across diverse loading and bridge conditions, enhancing the system’s applicability.

在公路或铁路交叉路口等关键位置高速移动的较重的轴可能会引起过度振动，对结构和乘客舒适度有害。为了解决这个问题，减震器可以调整，以有效地减少振动引起的移动车轮负载。传统的调谐质量系统和基于interter的设备由于需要大质量和运动部件而受到限制。为了克服这些挑战，本文介绍了一种新的基于负刚度惯性放大器的减振系统（NSIABVA）的理论公式，以减轻列车引起的振动。为了分析简支桥的动力特性，采用无量纲框架对连续荷载作用下的欧拉-伯努利梁进行了建模。此外，利用遗传算法对NSIABVA进行了优化，结果与Den Hartog的经典调谐质量系统理论非常吻合，验证了其准确性。所提出的NSIABVA结构在不同的频率和质量调谐比值下，通过显著的有效质量和刚度放大，提供了卓越的减振效果。传统的iabva可以减少50%-70%的排量，而NSIABVA可以减少70%-90%的排量。与IABVA主要提高耗能不同，NSIABVA还提高了阻尼和结构承载能力。此外，统计分析确定了不同荷载和桥梁条件下的最佳吸收器设计参数，提高了系统的适用性。

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引用次数: 0

Homogenizing elastic lattices with mechanisms 均质弹性晶格与机构

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-26 DOI: 10.1016/j.euromechsol.2025.105956

Basile Audoly , Claire Lestringant , Hussein Nassar

We propose an asymptotic method for homogenizing periodic elastic lattices that works in the presence of mechanisms, both of the macroscopic type (strain-producing modes) and of the microscopic type (internal modes). When a microscopic mechanism is present, the unit-cell problem produced by classical homogenization is singular. It can be fixed by including the amplitude

θ (X)

of the mechanism as an additional macroscopic degree of freedom (enrichment variable) contributing to the effective energy via its gradient

\nabla θ (X)

. When a macroscopic mechanism is present, homogenization delivers a degenerate effective energy at leading order, which can be regularized by accounting for the strain gradient. We introduce an asymptotic second-order homogenization scheme that integrates these two features: it delivers an effective energy capturing both the strain-gradient effect

\nabla ɛ (X)

relevant to macroscopic mechanisms, and the

\nabla θ (X)

regularization relevant to microscopic mechanisms, if any is present. The versatility of the approach is illustrated with a selection of lattices displaying a variety of effective behaviors. It follows a unified pattern that leads to a classification of these effective behaviors. Whereas the procedure delivers known effective models for elastic lattices without mechanisms, it can generate novel effective models for lattices possessing mechanisms.

我们提出了均匀化周期弹性晶格的渐近方法，该方法在宏观型（应变产生模式）和微观型（内部模式）存在的机制下工作。当存在微观机制时，由经典均匀化产生的单位胞问题是奇异的。它可以通过将机构的振幅θ(X)作为通过其梯度∇θ(X)贡献有效能量的附加宏观自由度（富集变量）来固定。当宏观机制存在时，均质提供了一阶简并有效能，该有效能可以通过考虑应变梯度而正则化。我们引入了一种集成了这两个特征的渐近二阶均匀化方案：它提供了一种有效的能量捕获与宏观机制相关的应变梯度效应∇θ(X)和与微观机制相关的正则化（如果存在的话）。通过选择显示各种有效行为的格来说明该方法的多功能性。它遵循一个统一的模式，将这些有效的行为分类。虽然该过程提供了已知的无机制弹性晶格的有效模型，但它可以为具有机制的晶格生成新的有效模型。

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引用次数: 0

Geometrically nonlinear dynamic analysis of multilayered organic solar cells with a non-classical plate theory and isogeometric anlysis 基于非经典板理论和等几何分析的多层有机太阳能电池几何非线性动力学分析

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-24 DOI: 10.1016/j.euromechsol.2025.105959

Shuo Liu , Kaifa Wang , Guigen Wang , Baolin Wang , Tinh Quoc Bui

As the spacecraft enters and maneuvers within its celestial orbit, the photovoltaic structures inevitably experience severe dynamic loading. It is imperative to investigate the dynamic mechanical properties in space structure design, as this is a crucial metric for evaluating the capability against impulsive loads. This study embeds isogeometric analysis (IGA) within a non-classical refined shear deformation theory (RSDT) incorporating the modified couple stress theory (MCST) to capture size-dependent geometrically nonlinear dynamics of organic solar cells (OSCs). Various parameters such as boundary conditions, damping, and loading types are considered. Numerical results confirm convergence and accuracy against established benchmarks. Results demonstrate that the size effects significantly enhance stiffness and reduce deflection. The geometrically nonlinear model lowers vibration amplitudes and prolongs periods. Considering damping, the energy system has been effectively dissipated. In addition, safety verification confirms that ITO (indium tin oxide) layer strains remain below critical thresholds under extreme loads. A semi-empirical formula is established, enabling direct estimation of the allowable dynamic load before brittle failure.

当航天器进入其天体轨道并在其天体轨道内机动时，光伏结构不可避免地要承受剧烈的动载荷。研究空间结构的动态力学性能是评估空间结构抗冲击能力的重要指标，在空间结构设计中具有十分重要的意义。本研究将等几何分析（IGA）嵌入到非经典精细剪切变形理论（RSDT）中，结合修正耦合应力理论（MCST）来捕捉有机太阳能电池（OSCs）的尺寸相关几何非线性动力学。考虑了各种参数，如边界条件、阻尼和加载类型。数值结果证实了与既定基准相比的收敛性和准确性。结果表明，尺寸效应显著提高了刚度，减小了挠度。几何非线性模型降低了振动幅值，延长了周期。考虑阻尼，能量系统得到有效耗散。此外，安全验证证实，在极端载荷下，ITO（氧化铟锡）层应变保持在临界阈值以下。建立了半经验公式，可以直接估计脆性破坏前的许用动载荷。

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引用次数: 0

Fracture mechanism in SUS304 during small punch tests SUS304的小冲孔断裂机理

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-24 DOI: 10.1016/j.euromechsol.2025.105953

Chong Gao , Yihui Huang , Qian Sun , Bo Cao , Takeshi Iwamoto , Tsutomu Umeda , Takayuki Kusaka

Past experimental result reveals that a region of the fracture initiation in metastable austenitic stainless steel SUS 304 during a small punch test changes from the loading side to free surface with respect to the loading rate. Since a measurement of a time series of the martensite and temperature distribution, which strongly affects the fracture behavior, is difficult to be realized during testing, a precise finite element (FE) analysis is necessary to support further discussions on the mechanism of the loading rate sensitivity. In the current work, the phenomena observed in the tests are precisely reproduced through the FE analyses including the martensitic transformation and the damage evolution modelled by authors. The condition for the onset of crack extension is provided to assist the future works in determining where the initiation occurs. Even though the austenitic phase is dominant for the fracture, a larger damage variable appears in the region where a significant quantity of martensite is distributed. Simultaneously, the work clarifies the influence of reducing the amount of martensite with respect to the loading rate on ductility of the material. In the dynamic loading, it is newly discovered that the thermal softening plays an important role, inducing the fracture from the free surface of the specimen.

以往的实验结果表明，在小冲孔试验中，亚稳奥氏体不锈钢sus304的断裂起始区域随加载速率从加载侧向自由表面变化。由于在试验过程中难以测量对断裂行为有强烈影响的马氏体和温度分布的时间序列，因此有必要进行精确的有限元分析，以支持进一步讨论加载速率敏感性的机制。在本工作中，通过有限元分析，包括马氏体相变和作者模拟的损伤演化，精确地再现了试验中观察到的现象。提供了裂纹扩展开始的条件，以协助今后的工作确定裂纹扩展开始的位置。尽管奥氏体相在断裂中占主导地位，但在大量分布马氏体的区域出现较大的损伤变量。同时，阐明了相对于加载速率减少马氏体含量对材料延展性的影响。在动加载过程中，新发现热软化起着重要的作用，从试件自由表面诱发断裂。

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引用次数: 0

Development of a Lagrange multiplier/cohesive zone approach for dynamic internal-interfacial crack interactions in laminated structures 基于拉格朗日乘子/内聚区方法的层合结构内部-界面裂纹动态相互作用研究

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-24 DOI: 10.1016/j.euromechsol.2025.105951

Yifang Qin , Shunhua Chen , Mitsuteru Asai

The main purpose of this work is to develop a nodal-based Lagrange multiplier/cohesive zone (LM/CZ) approach for accurate simulations of internal-interfacial crack interactions in laminated structures. The appeal of the presented approach lies in dealing with crack interactions in a natural and simple way, while inheriting the advantages of addressing the so-called artificial compliance issue and allowing for the use of non-matching meshes between structure layers. To achieve the end, the developed approach introduces the LM method to accurately enforce the continuity across nodes, and adopts a shifted traction separation law (TSL) to govern the subsequent cohesive crack behaviors. Internal and interfacial nodal groups are constructed, and the concept of ghost points is introduced to facilitate interfacial crack simulations with both matching and non-matching meshes in a unified way. Special attention is given to crack message transmission to effectively account for internal-interfacial crack interactions. The accuracy and effectiveness of the developed approach are demonstrated via benchmark examples. Finally, the capacity of the presented approach is further explored by extending the applications to crack interactions of two- and three-fiber/matrix units. Results show that our approach can effectively simulate complex crack interactions, including internal crack-induced interfacial crack as well as interfacial debonding triggered by internal cracks.

本工作的主要目的是开发一种基于节点的拉格朗日乘子/内聚区（LM/CZ）方法，用于精确模拟层合结构中内部-界面裂纹相互作用。所提出的方法的吸引力在于以自然和简单的方式处理裂缝相互作用，同时继承了解决所谓的人工顺应性问题和允许在结构层之间使用不匹配网格的优点。为了实现这一目标，该方法引入了LM方法来精确执行节点间的连续性，并采用了位移牵引分离律（TSL）来控制后续的内聚裂纹行为。构造内部节点群和界面节点群，引入虚点的概念，便于统一模拟匹配网格和非匹配网格的界面裂缝。特别注意裂缝信息的传输，以有效地解释内部-界面裂缝相互作用。通过基准算例验证了该方法的准确性和有效性。最后，通过扩展应用于两根和三根纤维/矩阵单元的裂纹相互作用，进一步探讨了所提出方法的能力。结果表明，该方法可以有效地模拟复杂的裂纹相互作用，包括内部裂纹引起的界面裂纹以及由内部裂纹引发的界面剥离。

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引用次数: 0

Corrigendum to “Hyperelastic nature of the Hoek–Brown criterion” [Europe. J. Mech. A/Solid. 115 (2026) 105782] “Hoek-Brown准则的超弹性性质”的勘误表[欧洲]。j .机械工程。A /固体。115 (2026) 105782]

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-23 DOI: 10.1016/j.euromechsol.2025.105945

I. Fontana , G. Bacquaert , D.A. Di Pietro , K. Kazymyrenko

引用次数: 0

Performance of nonlinear piezoelectric energy harvesting systems based on shear deformable beam theories 基于剪切变形梁理论的非线性压电能量收集系统性能研究

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-22 DOI: 10.1016/j.euromechsol.2025.105958

Guanghui Xia , Mingrui Liu , Yufeng Zhang , Jun Yin , Xiaofang Kang , Tingting Han , Leiyu Chen , Weiqiu Chen , C.W. Lim

Based on shear deformable beam models and Hamilton's principle, the governing equations considering geometric, inertial, and electromechanical coupling nonlinearity effects are established and solved. The nonlinear partial differential equations are decoupled and reduced to a lower-order form via the Galerkin method. The technique of multiple scales is then applied to derive the approximate analytical solutions. Subsequently, analytical formulations for vibration displacement, harvested voltage, and electrical power output are established. Based on Timoshenko Beam Model (TM) and Euler-Bernoulli Beam Model (EBM), this study examines how excitation intensity, damping properties, external resistance, and tip mass influence the amplitude-frequency characteristics and stability of energy harvesters with varying length-to-thickness ratios. The results indicate that for structures with a low length-to-thickness ratio, the TM yields more accurate computational solutions. Furthermore, appropriate adjustment of the damping properties and external resistance enhances the stability of energy harvesting performance under low-frequency resonance, thereby augmenting the power conversion capability of resonant piezoelectric harvesters.

基于剪切变形梁模型和Hamilton原理，建立并求解了考虑几何、惯性和机电耦合非线性效应的控制方程。利用伽辽金方法将非线性偏微分方程解耦并简化为低阶形式。然后应用多尺度技术求出近似解析解。随后，建立了振动位移、收获电压和电力输出的解析公式。基于Timoshenko梁模型（TM）和Euler-Bernoulli梁模型（EBM），本研究考察了激励强度、阻尼特性、外部电阻和尖端质量如何影响不同长厚比的能量采集器的幅频特性和稳定性。结果表明，对于长厚比较低的结构，TM的计算结果更为精确。此外，适当调整阻尼特性和外电阻，提高了低频谐振下能量收集性能的稳定性，从而提高了谐振式压电采集器的功率转换能力。

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引用次数: 0

Influence of heat treatment on microstructure and mixed-mode fracture behaviour of additively manufactured 316L stainless steel 热处理对增材制造316L不锈钢组织及混合模式断裂行为的影响

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-21 DOI: 10.1016/j.euromechsol.2025.105949

Cansin Ozdogan , Rasid A. Yildiz , Luciana Tavares , Ozkan Gokcekaya , Mohammad Malekan

Additive manufacturing (AM) has significant advantages over traditional production methods, including reduced material waste and enhanced design freedom. One of the dominant AM processes, laser powder bed fusion (L-PBF), relies on important process parameters—scanning speed, layer thickness, and laser power—whose settings determine the microstructure and mechanical properties of L-PBF-printed parts. In this study, correlation of microstructure and macro-mechanical fracture behaviour of L-PBF-printed 316L stainless steel material is investigated. It also contains comparison of as-built and heat-treated specimens at 700 °C, 900 °C, and 1100 °C on force-displacement curves and microstructure. Arcan fixture was employed to analyse mixed-mode fracture behaviour, and microstructural examination of fracture surfaces uses scanning electron microscopy, X-ray diffractometer, and electron backscatter diffraction. Apart from that, Johnson Cook plasticity theory was applied to as-built Arcan specimens under pure shear, mixed mode, and tensile loadings with Abaqus/CAE software. Influence of porosity in mechanical behaviour was sought on comparing experimental and numerical results. As a result, numerical results were extremely in line with experiments. The findings provide a correlation of micro-scale properties, fracture properties, and L-PBF process parameters and provide insights on the optimization of AM component design and performance.

与传统的生产方法相比，增材制造（AM）具有显著的优势，包括减少材料浪费和提高设计自由度。作为主流增材制造工艺之一，激光粉末床熔融（L-PBF）依赖于重要的工艺参数——扫描速度、层厚度和激光功率，这些参数的设置决定了L-PBF打印件的微观结构和力学性能。研究了l - pbf打印316L不锈钢材料的微观组织与宏观力学断裂行为的相关性。它还包含了在700°C， 900°C和1100°C的力-位移曲线和微观结构上的构建和热处理样品的比较。使用Arcan夹具分析混合模式断裂行为，并使用扫描电镜、x射线衍射仪和电子背散射衍射对断口表面进行微观结构检查。此外，利用Abaqus/CAE软件，将Johnson Cook塑性理论应用于Arcan试件在纯剪切、混合模式和拉伸载荷下的原状。通过对实验结果和数值结果的比较，寻求孔隙率对力学行为的影响。结果表明，数值计算结果与实验结果非常吻合。研究结果提供了微尺度性能、断裂性能和L-PBF工艺参数之间的相关性，并为增材制造部件的设计和性能优化提供了见解。

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引用次数: 0

Nonlinear oscillations and chaotic behavior of sandwich cylindrical shells with auxetic core and FG face sheets 带辅助芯和FG面板夹层圆柱壳的非线性振动和混沌行为

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-21 DOI: 10.1016/j.euromechsol.2025.105955

Soheil Hashemi , Amin Rezaeezadeh

Auxetic materials are novel substances that create significant research opportunities for scientists due to their negative Poisson's ratio. This study presents an analysis of the nonlinear forced vibrations and chaotic behavior of auxetic-core sandwich cylindrical shells (AXC-SCSs) with functionally graded (FG) skins subjected to harmonic loading. To achieve this, the governing equations of the system are derived using first-order shear deformation theory (FSDT) and the von Karman relations. The displacement field is expressed in terms of 24 generalized coordinates corresponding to the driven, companion, and axisymmetric modes of simply supported shells. Subsequently, the multi-mode Galerkin and static condensation methods are applied to convert the partial differential equations into a set of four-degree-of-freedom nonlinear ordinary differential equations. Finally, the nonlinear four-degree-of-freedom equations are solved analytically using the multiple-time-scale method. The main novelty of this research lies in the incorporation of strong nonlinear coupling between driven and companion modes in the AXC-SCS, enabling a precise prediction of nonlinear oscillation behaviors. In the results section, the obtained findings are verified by comparison with previously published studies and numerical solutions. Finally, the effects of system parameters on the nonlinear frequency response, time history, phase-plane, and bifurcation diagrams are studied. The findings reveal that an increase in the inclined rib angle (θ) and the cell thickness-to-inclined rib length ratio (t/l), along with a decrease in the horizontal-to-inclined rib length ratio (w/l), enhances the hardening behavior and narrows the resonance region of the shell. However, when the companion mode is included, these trends are reversed. Time-history analyses show that increasing θ and t/l, and decreasing w/l, reduce the vibration amplitude. The proposed analytical framework provides a reliable and efficient tool for predicting and controlling nonlinear dynamic responses in a sandwich shell with an auxetic structure.

补充材料是一种新型物质，由于其负泊松比，为科学家创造了重要的研究机会。本文研究了具有功能梯度（FG）蒙皮的外源芯夹层圆柱壳（axc - scs）在谐波荷载作用下的非线性强迫振动和混沌行为。为此，利用一阶剪切变形理论（FSDT）和von Karman关系推导了系统的控制方程。位移场用24个广义坐标表示，对应于简支壳的驱动模态、伴模态和轴对称模态。然后，采用多模伽辽金和静态凝聚方法将偏微分方程转化为一组四自由度非线性常微分方程。最后，采用多时间尺度法对非线性四自由度方程进行解析求解。该研究的主要新颖之处在于在AXC-SCS中加入了驱动模式和伴随模式之间的强非线性耦合，从而能够精确预测非线性振荡行为。在结果部分，通过与先前发表的研究和数值解的比较，验证了所获得的发现。最后，研究了系统参数对非线性频率响应、时程、相平面和分岔图的影响。结果表明：斜肋角（θ）和单元厚度与斜肋长比（t/l）的增大，水平与斜肋长比（w/l）的减小，增强了壳体的硬化性能，缩小了壳体的共振区；然而，当包括伴侣模式时，这些趋势就会逆转。时程分析表明，增大θ和t/l，减小w/l，振动幅值减小。所提出的分析框架为预测和控制夹层结构的非线性动力响应提供了可靠和有效的工具。

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引用次数: 0

Deep learning based inverse design of metamaterials for vibration control 基于深度学习的超材料振动控制逆设计

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-21 DOI: 10.1016/j.euromechsol.2025.105957

Chunfeng Zhao , Tian Zhang , Ao Huang , Qiaoyun Wu , Zhenyu Chen

Multi-source vibration control is of great importance to human comfort and the built environment, and metamaterials offer an efficient pathway for low-frequency vibration control. However, traditional metamaterial design approaches are often limited by computational efficiency and empirically guided iterative optimization processes. In this study, we present an inverse design methodology for metamaterials that utilizes deep learning models to achieve target bandgap characteristics and transmission loss specifications. The metamaterials are initially parameterized using parametric Bezier curves, and the unit-cell image is downscaled with an encoder from the variational autoencoder (VAE) model. Two inverted transformer (iTransformer) models are trained to predict the dispersion relations and transmission loss curves using the data obtained from the finite element method (FEM), respectively. An iTransformer-VAE-guided genetic algorithm is subsequently employed to inversely generate the geometrical parameters of the metamaterials by specifying the target bandgap and transmission loss profiles. Finally, metamaterials designed using this approach exhibit varying bandgaps and transmission losses, which are then validated against numerical and experimental results. The results indicate that a relative bandgap width error of 1.97 % and an average transmission loss error of 10.83 % for the inversely design metamaterials. Time history analysis and experimental validation further reveal that the proposed metamaterials can attenuate vibration waves by up to 96.09 % when the dominant frequency lies within the bandgap ranges. This study can provide a valuable reference for both transmission characteristics prediction and inverse design of metamaterials.

多源振动控制对人体舒适性和建筑环境具有重要意义，而超材料为低频振动控制提供了有效途径。然而，传统的超材料设计方法往往受到计算效率和经验指导迭代优化过程的限制。在这项研究中，我们提出了一种利用深度学习模型来实现目标带隙特性和传输损耗规格的超材料逆设计方法。超材料最初使用参数化贝塞尔曲线进行参数化，并使用变分自编码器（VAE）模型的编码器对单位细胞图像进行缩小。利用有限元法得到的数据，分别训练了两个逆变变压器模型来预测频散关系和传输损耗曲线。随后，通过指定目标带隙和传输损耗曲线，采用ittransformer - vee引导的遗传算法反向生成超材料的几何参数。最后，使用这种方法设计的超材料表现出不同的带隙和传输损耗，然后根据数值和实验结果进行验证。结果表明，反向设计的超材料的相对带隙宽度误差为1.97%，平均传输损耗误差为10.83%。时程分析和实验验证进一步表明，当主导频率在带隙范围内时，所提出的超材料对振动波的衰减率高达96.09%。该研究可为超材料的传输特性预测和逆向设计提供有价值的参考。

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引用次数: 0