International Journal of Solids and Structures最新文献_第5页

Exact analysis of bending of a heterogeneous plate with irregularly-shaped inclusions 含不规则形状夹杂物的非均质板弯曲的精确分析

IF 3.8 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2026-01-02 DOI: 10.1016/j.ijsolstr.2025.113828

Emad Hasrati, Ankur Jain

Composite and functionally graded materials are used commonly in a broad variety of engineering systems. This work presents theoretical bending analysis of a simply supported heterogeneous rectangular plate containing discrete inclusions of irregular shapes. The commonly used governing equation for a homogeneous plate is generalized by accounting for inclusions of irregular shapes and different mechanical properties embedded within the plate. The heterogeneous plate problem is then solved by representing the spatial distributions of elastic moduli and Poisson’s ratios using Heaviside functions, thereby enabling an exact and efficient modeling of sharp discontinuities in these properties at the plate-inclusion interfaces. A series solution for the displacement field is derived using the integral and differential properties of the Heaviside function. The derivation is an exact generalized approach to handle multi-inclusion configurations with nonuniform properties, in contrast with previously presented approximate techniques such as homogenization and laminate approximation. Results are shown to reduce to the well-known Navier solution under special conditions. Good agreement with independent finite element simulations is also shown. A key finding of this work is that the location and shape of discrete inclusions, particularly their intersection with the high-bending regions of the plate, significantly influence the magnitude and spatial distribution of transverse deflection. Notably, stiff inclusions tend to displace the deflection peak away from themselves, while soft inclusions attract it, and in both cases, proximity to the plate boundaries can reverse these trends due to geometric and support-induced constraints. The technique developed here enables analysis of a number of practical problems comprising heterogeneous composites, as demonstrated through several examples. In addition to extending the state-of-the-art in theoretical analysis of composite structures, this work may also find practical applications in a number of engineering systems where such materials are used commonly.

复合材料和功能梯度材料广泛应用于各种工程系统中。这项工作提出了包含不规则形状离散夹杂物的简支非均质矩形板的理论弯曲分析。通过考虑嵌在板内的不规则形状和不同力学性能的夹杂物，推广了常用的均匀板控制方程。然后通过使用Heaviside函数表示弹性模量和泊松比的空间分布来解决非均质板问题，从而能够精确有效地模拟板-包裹体界面上这些属性的尖锐不连续。利用Heaviside函数的积分和微分性质，导出了位移场的级数解。与先前提出的近似技术（如均匀化和层压近似）相比，该推导是一种精确的广义方法来处理具有非均匀性质的多包含配置。结果表明，在特殊条件下，其解可约化为众所周知的纳维耶解。与独立有限元模拟结果吻合较好。这项工作的一个关键发现是，离散夹杂物的位置和形状，特别是它们与板块高弯曲区域的相交，显著影响横向挠度的大小和空间分布。值得注意的是，硬包裹体倾向于将偏转峰从自身移开，而软包裹体则吸引它，在这两种情况下，由于几何和支撑诱导的约束，靠近板块边界可以扭转这些趋势。本文开发的技术可以分析包含异质复合材料的许多实际问题，如通过几个示例所演示的那样。除了扩展复合材料结构理论分析的最新技术外，这项工作还可以在许多通常使用这种材料的工程系统中找到实际应用。

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引用次数: 0

Triangular lattice metamaterials in curved beam structures: Free vibration analysis with strain gradient beam models 弯曲梁结构中的三角形晶格超材料：应变梯度梁模型的自由振动分析

IF 3.8 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2025-12-30 DOI: 10.1016/j.ijsolstr.2025.113827

Zeinab Soleimani Javid, Jarkko Niiranen

The current study investigates the free vibration behavior of curved beams made of triangular lattice metamaterials. The focus of the study is in simplifying the standard computational analysis by a novel approach of modeling curved lattice structures as homogenized Euler–Bernoulli and Timoshenko beams within the strain gradient theory, to incorporate size effects possessed by lattice structures. The governing equations of the strain gradient beam models are derived through variational methods, and solutions are obtained by using the differential quadrature method. Detailed finite element analyses are adopted for validation. The study examines the effects of thickness, lattice size, center angle and boundary conditions on stiffness and vibration characteristics, demonstrating that the strain gradient beam models provide accurate results unlike the corresponding classical beam models. The findings on the mechanical behavior and modeling approach have practical applications in industries such as aerospace and automotive manufacturing, where lightweight and stiff structures are critical for performance adaptation and optimization.

本文研究了三角形晶格超材料弯曲梁的自由振动特性。本研究的重点是通过在应变梯度理论中将弯曲晶格结构建模为均质Euler-Bernoulli和Timoshenko梁的新方法来简化标准计算分析，以纳入晶格结构所具有的尺寸效应。采用变分法推导了应变梯度梁模型的控制方程，并采用微分正交法求解。采用详细的有限元分析进行验证。研究考察了厚度、晶格尺寸、圆心角和边界条件对梁刚度和振动特性的影响，表明应变梯度梁模型与相应的经典梁模型相比提供了准确的结果。机械行为和建模方法的研究结果在航空航天和汽车制造等行业具有实际应用价值，在这些行业中，轻量化和刚性结构对性能适应和优化至关重要。

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引用次数: 0

Coupling negative Poisson’s ratio with multifunctionality: advances in auxetic metamaterials 耦合负泊松比与多功能性：增减超材料的研究进展

IF 3.8 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2025-12-28 DOI: 10.1016/j.ijsolstr.2025.113822

Chuanbiao Zhang , Fucong Lu , Kelan Mo , Yi He , Yang Liu , Yilin Zhu

Auxetic metamaterials with negative Poisson’s ratio are rapidly advancing from specialized mechanical systems to multifunctional platforms that couple structural performance with unconventional thermal, acoustic, electrical, magnetic, and optical responses. Their unique deformation mechanisms concentrate and redistribute strain energy, thereby enhancing stiffness, strength, and energy absorption while simultaneously interacting with external fields. This review provides a comprehensive synthesis of recent progress in design strategies and coupling mechanisms, highlighting approaches based on geometric reconfiguration, instability engineering, hierarchical structuring, and multi-material integration. It further elucidates how auxetic structures regulate thermal expansion, dissipate impact energy, and manipulate wave propagation across broad frequency ranges, offering unprecedented opportunities for adaptive and programmable materials. Application prospects span biomedicine, aerospace, civil infrastructure, and soft robotics. However, significant challenges remain in scalable manufacturing, durability under coupled loading, and predictive multi-physics modeling. Despite these advances, fundamental gaps persist in understanding the multiphysics coupling mechanisms and in developing scalable design frameworks. This review seeks to bridge these gaps by systematically clarifying the deformation principles, coupling strategies, and application pathways of multifunctional auxetic metamaterials. Future progress is expected to depend on the integration of topology optimization, advanced fabrication techniques, and system-level demonstrations, which together will accelerate the translation of multifunctional auxetic metamaterials into high-performance technologies ready for practical application.

具有负泊松比的辅助超材料正迅速从专门的机械系统发展到多功能平台，将结构性能与非常规的热、声、电、磁和光学响应相结合。它们独特的变形机制集中并重新分配了应变能，从而在与外场相互作用的同时提高了刚度、强度和能量吸收。本文综述了设计策略和耦合机制的最新进展，重点介绍了基于几何重构、不稳定性工程、分层结构和多材料集成的方法。它进一步阐明了增减结构如何调节热膨胀，消散冲击能量，并在宽频率范围内操纵波的传播，为自适应和可编程材料提供了前所未有的机会。应用前景涵盖生物医学、航空航天、民用基础设施和软机器人。然而，在可扩展制造、耦合载荷下的耐用性和预测性多物理场建模方面仍存在重大挑战。尽管取得了这些进展，但在理解多物理场耦合机制和开发可扩展设计框架方面仍然存在根本性的差距。本文旨在通过系统地阐明多功能形变超材料的变形原理、耦合策略和应用途径来弥补这些空白。未来的进展预计将取决于拓扑优化、先进制造技术和系统级演示的集成，它们将共同加速多功能增塑型超材料向高性能技术的转化，为实际应用做好准备。

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引用次数: 0

Modelling the elastic properties of woven composites with transverse bundle cracks 具有横向束裂纹的机织复合材料弹性性能建模

IF 3.8 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2025-12-27 DOI: 10.1016/j.ijsolstr.2025.113823

Paolo Andrea Carraro, Federico Lamon, Lucio Maragoni, Marino Quaresimin

Transverse bundle cracks are typically the first observable damage mechanism in woven composites under quasi-static and cyclic loadings. The number of cracks, or their density, increases with the load or the number of cycles causing a degradation of the laminate stiffness. In this work, two different modelling approaches are proposed to predict the in-plane apparent elastic properties of woven composites in the presence of cracks in the transverse bundles. The models account for the fabric mesostructure, including the bundle waviness. Comparisons with numerical simulations and experimental data reveals the accuracy of the proposed models, making them a useful tool in a mechanistic framework for the prediction of progressive stiffness loss in woven composites.

横向束裂纹是编织复合材料在准静态和循环载荷作用下最先观察到的损伤机制。裂纹的数量或它们的密度随着载荷或循环次数的增加而增加，从而导致层压板刚度的退化。在这项工作中，提出了两种不同的建模方法来预测编织复合材料在横向束中存在裂纹时的面内表观弹性性能。该模型考虑了织物的细观结构，包括束的波纹度。通过与数值模拟和实验数据的比较，揭示了所提模型的准确性，使其成为预测编织复合材料渐进刚度损失的一个有用的机制框架工具。

引用次数: 0

Theoretical modeling and tailored design of mechanoelectrical behavior in flexible piezoelectric metamaterials 柔性压电材料机电特性的理论建模与定制设计

IF 3.8 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2025-12-26 DOI: 10.1016/j.ijsolstr.2025.113818

Xianxian He, Suyun Li, Yifeng Dong, Ying Li

Flexible piezoelectric metamaterials offer transformative opportunities for sensing, energy transduction, and bioinspired electronics, yet their development is constrained by limited geometric tunability and the lack of unified models capable of describing complex 3D architectures under large deformations. Inspired by the hierarchical helical motifs found in collagen fibers, this study proposes a spindle-shaped helical microstructure as the fundamental unit of a flexible piezoelectric metamaterial and establishes a comprehensive theoretical framework to characterize its nonlinear mechanoelectrical behavior. By integrating Kirchhoff rod theory with piezoelectric constitutive relations, the proposed model explicitly incorporates helical geometric parameters and provides a direct quantitative relationship between mechanical strain and electrical response. Finite element simulations and targeted experiments validate the predictive accuracy of the theoretical model across a wide range of loading conditions. Systematic parametric analyses reveal that the normalized width R/d₀ governs critical strain, stiffness evolution, and strain-dependent electrical output, while also influencing global buckling and the relative importance of flexoelectric effects. Leveraging these structure–property relationships, we demonstrate that the metamaterial can reproduce nonlinear and anisotropic mechanical behaviors characteristic of biological tissues and generate physiologically relevant electrical signals. The framework further enables the rational design of topological architectures with programmable mechanical adaptability and tunable sensing performance. Overall, this work provides a unified theoretical and computational foundation for the design of flexible piezoelectric metamaterials with complex 3D geometries and nonlinear deformation characteristics. The proposed materials exhibit high structural programmability, robust sensing capabilities, and significant potential for next-generation wearable electronics, biomedical interfaces, and intelligent soft systems.

柔性压电超材料为传感、能量转导和生物启发电子学提供了变革的机会，但它们的发展受到有限的几何可调性和缺乏能够描述大变形下复杂3D结构的统一模型的限制。受胶原纤维中发现的分层螺旋基序的启发，本研究提出了一个纺锤形螺旋微结构作为柔性压电超材料的基本单元，并建立了一个全面的理论框架来表征其非线性机电行为。通过将Kirchhoff杆理论与压电本构关系相结合，该模型明确地包含了螺旋几何参数，并提供了机械应变与电响应之间的直接定量关系。有限元模拟和目标实验验证了理论模型在大范围加载条件下的预测准确性。系统参数分析表明，归一化宽度R/d0控制临界应变、刚度演化和应变相关的电输出，同时也影响整体屈曲和挠曲电效应的相对重要性。利用这些结构-性能关系，我们证明了这种超材料可以再现生物组织的非线性和各向异性力学行为特征，并产生生理相关的电信号。该框架进一步实现了具有可编程机械适应性和可调传感性能的拓扑结构的合理设计。总体而言，本工作为具有复杂三维几何形状和非线性变形特性的柔性压电超材料的设计提供了统一的理论和计算基础。所提出的材料具有高结构可编程性，强大的传感能力，以及下一代可穿戴电子产品，生物医学接口和智能软系统的巨大潜力。

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引用次数: 0

The tip region of a shallow hydraulic fracture 浅水力裂缝的尖端区域

IF 3.8 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2025-12-26 DOI: 10.1016/j.ijsolstr.2025.113821

Yu-Hua Zhang , Emmanuel Detournay , Le-Tian Zheng , Zhi-Qiao Wang

This study develops a traveling-wave solution for the tip region of a shallow hydraulic fracture by analyzing the problem of a semi-infinite fracture propagating at constant velocity parallel to a free surface. The semi-fracture is driven by a far-field bending moment and a fluid pressure governed by the lubrication equation. The geometric and mechanical asymmetry introduced by the free surface gives rise to a mixed-mode fracture, described through a system of coupled elasticity equations for the shear and normal displacement jumps. The analysis assumes that the fluid front coincides with the fracture tip, thereby neglecting the existence of a fluid-lag zone. A scaling analysis reveals that the solution depends on a single parameter, the dimensionless fracture toughness

K

. The relationship between the far-field bending moment and fracture toughness is established by applying a mixed-mode propagation criterion and accounting for viscous fluid flow. Results indicate the dependence of the fracture-tip response on

K

: for sufficiently small

K

, the solution transitions to pure mode II, accompanied by the development of a sliding contact zone whose length increases as toughness decreases. These findings provide new insight into the propagation of shallow hydraulic fractures and highlight the role of substrate elasticity in governing tip processes.

本文通过分析平行于自由面匀速扩展的半无限裂缝问题，建立了浅层水力裂缝尖端区域的行波解。半断裂由远场弯矩和由润滑方程控制的流体压力驱动。自由表面引入的几何和力学不对称导致了混合模式断裂，通过剪切和法向位移跳跃的耦合弹性方程系统来描述。该分析假设流体前缘与裂缝尖端重合，从而忽略了流体滞后带的存在。尺度分析表明，解依赖于单一参数，即无因次断裂韧性k。采用混合模式传播准则并考虑粘性流体流动，建立了远场弯矩与断裂韧性之间的关系。结果表明，断裂尖端响应与K有关：当K足够小时，溶液转变为纯II型，并伴有滑动接触区的发展，该区域的长度随着韧性的减小而增加。这些发现为浅层水力裂缝的扩展提供了新的见解，并强调了基底弹性在控制尖端过程中的作用。

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引用次数: 0

Torsion design and analysis of space frame based on deformation matching 基于变形匹配的空间框架抗扭设计与分析

IF 3.8 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2025-12-26 DOI: 10.1016/j.ijsolstr.2025.113824

Kaixuan Liang , Panxu Sun , Shuxia Wang , Dongwei Wang

The torsion design of the space frame is facing challenges due to factors such as complex deformation coupling and interaction between global and local stability. In this study, the deformation decomposition method was used to quantitatively analyze the torsional deformation of a rectangular-section space frame. Based on the decomposition results, the transformation relationship between torsional deformation and antisymmetric shear deformation can be obtained. Therefore, this paper attempts to improve the torsional performance of space frames by resisting antisymmetric shear deformation. Based on the space frame without diagonal bars, three targeted structural design schemes were proposed and specimens were fabricated by Selective Laser Melting (SLM). The rotation angle and torque data of the specimens were obtained by torsion experiment, and the torsion deformation projection coefficient was obtained by digital image correlation (DIC) and the deformation decomposition method. The results indicate that arranging antisymmetric single diagonal bars on opposite sides increases the torsional bearing capacity of the space frame by 140.49 %∼262.94 % and reduces the torsional deformation projection coefficient by 97.29 %∼97.59 %. Furthermore, configuring double diagonal bars yields a more significant improvement, increasing the torsional bearing capacity by 550.64 % and decreasing the torsional deformation projection coefficient by 99.32 %.

由于复杂的变形耦合和整体稳定与局部稳定的相互作用等因素，空间框架的扭转设计面临挑战。本文采用变形分解方法对矩形截面空间框架的扭转变形进行了定量分析。根据分解结果，可以得到扭转变形与反对称剪切变形之间的转换关系。因此，本文试图通过抵抗反对称剪切变形来提高空间框架的抗扭性能。基于无对角杆的空间框架，提出了三种有针对性的结构设计方案，并采用选择性激光熔化（SLM）法制备了试件。通过扭转实验获得试件的旋转角度和扭矩数据，通过数字图像相关（DIC）和变形分解方法获得试件的扭转变形投影系数。结果表明，在相对两侧布置反对称单根对角杆可使空间框架的抗扭承载力提高140.49% ~ 262.94%，扭转变形投射系数降低97.29% ~ 97.59%。此外，配置双对角杆对扭转承载力的改善更为显著，扭转承载力提高了550.64%，扭转变形投射系数降低了99.32%。

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引用次数: 0

Competitive fracture propagation across different regimes during multi-stage hydraulic fracturing 多级水力压裂过程中不同状态下竞争性裂缝扩展

IF 3.8 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2025-12-25 DOI: 10.1016/j.ijsolstr.2025.113817

Mengli Li , Fengshou Zhang , Mengyi Li , Egor Dontsov , Alexander Valov , Tuo Wang

It is crucial to understand how multiple hydraulic fractures interact with each other to improve effectiveness of fracturing treatments. This study employs a fully coupled DEM-based hydraulic fracture model to investigate the effect of intra- and inter-stage stress shadowing across different propagation regimes under limited entry conditions. Fracture propagation is modeled during injection and shut-in, with the coupled hydro-mechanical scheme validated against existing analytical solutions for radial fractures. The results show that the competitive propagation of multiple fractures is influenced by the fracture propagation regime, stress orientation angle and fracture spacing. Fractures tend to grow uniformly in the viscosity-dominated regime, whereas in the toughness-dominated regime, fractures exhibit petal-like shapes with directional growth preferences. The interaction between fractures during shut-in further complicates the process. Inter-stage stress shadowing promotes secondary propagation of early-stage fractures due to compression stress caused by later fractures, resulting in more significant variations in fracture radii across stages. In contrast, intra-stage stress shadowing causes multiple fractures within a single stage to deviate from symmetrical growth. The stress orientation angle, however, has a relatively minor effect on fracture morphology. As fracture spacing increases, the effect of stress shadowing diminishes, allowing each fracture to behave more like an isolated fracture in its respective propagation regime.

了解多个水力裂缝如何相互作用，对于提高压裂处理的有效性至关重要。本研究采用基于全耦合dem的水力裂缝模型，研究了在有限进入条件下，不同扩展模式下段内和段间应力阴影的影响。在注入和关井期间对裂缝扩展进行建模，并根据现有的径向裂缝解析解验证了耦合的水力-力学方案。结果表明：多裂缝的竞争扩展受裂缝扩展方式、应力取向角和裂缝间距的影响；在粘度主导下，裂缝趋向于均匀生长，而在韧性主导下，裂缝呈现花瓣状形状，具有定向生长偏好。在关井过程中，裂缝之间的相互作用进一步复杂化了这一过程。由于后期裂缝产生的压缩应力，段间应力阴影促进了早期裂缝的二次扩展，导致裂缝半径在不同阶段的变化更为显著。相反，段内应力阴影会导致单段内多条裂缝偏离对称生长。而应力取向角对裂缝形态的影响相对较小。随着裂缝间距的增加，应力阴影的影响会减弱，从而使每条裂缝在其各自的扩展状态下表现得更像一条孤立的裂缝。

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引用次数: 0

High-frequency vertical vibration of a rigid impermeable disk on a saturated poroelastic half-space 饱和孔弹性半空间上刚性不透水圆盘的高频垂直振动

IF 3.8 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2025-12-24 DOI: 10.1016/j.ijsolstr.2025.113816

Linlong Mu , Tao Zhou , Yimin Lu , Maosong Huang

Understanding the vertical dynamic impedance of rigid foundations on saturated soils is critical for offshore and marine infrastructure design but remains challenging due to coupled solid–fluid interactions and complex boundary conditions. While previous studies often assume interface conditions − either fully permeable or fully impermeable, practical scenarios like suction bucket involve mixed-permeability boundaries, a problem rarely addressed rigorously under high-frequency excitation. This study presents a semi-analytical solution for the high-frequency vertical vibration of a rigid impermeable circular disk resting on a saturated poroelastic half-space. The governing equations, derived from Biot’s theory, are solved using displacement potential functions and Hankel integral transforms, fully incorporating the compressibility of both the soil skeleton and pore fluid. A dual integral equation describing the mixed boundary conditions at the impermeable disk interface is established and transformed into a numerically solvable second-kind Fredholm integral equation. The solution is validated against time-domain finite element simulations and classical results, showing excellent agreement across a wide frequency range. Parametric studies reveal that Poisson’s ratio and porosity significantly influence dynamic compliance in the high-frequency regime, while the compressibility of the solid and fluid phases plays a minor role. Interface permeability is shown to substantially affect the dynamic response in highly permeable soils, but has negligible impact in low-permeability conditions. These findings enhance the theoretical framework for soil-structure interaction in saturated media and provide a robust tool for designing dynamically loaded seabed-mounted foundations.

了解饱和土壤上刚性基础的垂直动力阻抗对于海上和海洋基础设施的设计至关重要，但由于固-流耦合相互作用和复杂的边界条件，仍然具有挑战性。虽然以前的研究通常假设界面条件-完全渗透或完全不渗透，但实际情况（如吸力桶）涉及混合渗透边界，这一问题很少在高频激励下得到严格解决。本文研究了饱和孔弹性半空间上刚性不透水圆盘的高频垂直振动的半解析解。控制方程由Biot理论导出，利用位移势函数和Hankel积分变换求解，充分考虑了土骨架和孔隙流体的可压缩性。建立了描述不透水盘界面混合边界条件的对偶积分方程，并将其转化为数值可解的第二类Fredholm积分方程。通过时域有限元仿真和经典结果验证了该方法的有效性，在较宽的频率范围内显示出良好的一致性。参数化研究表明，泊松比和孔隙率对高频区动态柔度有显著影响，而固相和流相的可压缩性影响较小。界面渗透性对高渗透土的动力响应有显著影响，而对低渗透土的影响可以忽略不计。这些发现增强了饱和介质中土-结构相互作用的理论框架，并为设计动态加载的海床基础提供了强有力的工具。

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引用次数: 0

Effects of nonlinear viscoelasticity on the stability of 3D-printed metamaterials 非线性粘弹性对3d打印超材料稳定性的影响

IF 3.8 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2025-12-23 DOI: 10.1016/j.ijsolstr.2025.113815

D.H. Tumarada, V. Ravulapalli, G. Raju

In recent years, 3D-printed mechanical metamaterials have gained prominence in the field of soft structures to realize unprecedented mechanical functionalities. These structures are being architected using beam geometries to exploit their bistable configuration for energy absorption or locomotion applications. The viscous properties of flexible materials are usually overlooked in their design, which can affect their stability transitions, specifically in dynamic applications. Hence, this work investigates the influence of nonlinear viscoelasticity on the stability of a 3D-printed unit cell, a building block of metamaterials. Using a systematic parametric study, a cosine-shaped housing unit cell is designed and 3D-printed in Thermoplastic polyurethane (TPU), a material that has earned increasing attention for its flexibility. Material characterization is carried out to calibrate a three-network model that accurately captures the nonlinear viscous properties of TPU for finite element (FE) simulations. A 3D-printed unit cell is tested under axial compression, and its full-field response, captured using a 3D-Digital Image Correlation setup, is used to validate the FE model. Subsequently, experiments are carried out by varying the loading rates and boundary conditions, and the influence of the viscous dissipation on the stability transitions in a unit cell is investigated using FE. The stability transitions of the unit cell from monostable or bistable to pseudobistable states are studied using the dynamic evolution of total elastic strain energy. The results of this study emphasize the vital role of material properties in designing 3D-printed soft metamaterials for energy absorption or soft robotic applications.

近年来，3d打印机械超材料在软结构领域崭露头角，实现了前所未有的机械功能。这些结构正在使用梁的几何结构来开发其双稳态配置，用于能量吸收或运动应用。柔性材料的粘性特性通常在其设计中被忽视，这可能会影响其稳定性转变，特别是在动态应用中。因此，这项工作研究了非线性粘弹性对3d打印单元细胞稳定性的影响，单元细胞是超材料的组成部分。通过系统参数研究，设计了一个余弦形状的外壳单元，并用热塑性聚氨酯（TPU）进行3d打印，这种材料因其灵活性而受到越来越多的关注。进行材料表征以校准三网络模型，该模型可准确捕获TPU的非线性粘性特性，用于有限元模拟。在轴向压缩下测试3d打印的单元格，并使用3d数字图像相关设置捕获其全场响应，用于验证FE模型。随后，通过改变加载速率和边界条件进行了实验，并利用有限元方法研究了粘性耗散对单元胞内稳定性转变的影响。利用总弹性应变能的动态演化，研究了单稳态或双稳态向准双稳态的转变。这项研究的结果强调了材料性能在设计用于能量吸收或软机器人应用的3d打印软超材料中的重要作用。

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引用次数: 0