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【新文速递】2024年5月2日固体力学SCI期刊最新文章

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今日更新:International Journal of Solids and Structures 1 篇,Mechanics of Materials 1 篇,International Journal of Plasticity 1 篇,Thin-Walled Structures 8 篇

International Journal of Solids and Structures

A granular micromechanic-based model for Ultra High Performance Fiber-Reinforced Concrete (UHP FRC)

Luca Placidi, Francesco dell’Isola, Abdou Kandalaft, Raimondo Luciano, Carmelo Majorana, Anil Misra

doi:10.1016/j.ijsolstr.2024.112844

超高性能纤维增强混凝土(UHP FRC)的颗粒细观力学模型

There is a growing interest in the application of UHP FRC (Ultra-High Performance Fiber-Reinforced Concrete) which has been under vigorous development since its inception over two decades ago. The advantages of these advanced materials is that they overcome the problems that plague conventional concrete, these include among others low residual strength and low tensile strength, poor crack control and resistance to crack propagation, which leads corrosion of the rebars and spalling. The aim of this paper is to provide a granular micromechanics-based model to describe the deformation behavior of UHP FRC material as it gives a robust method to link the micro-scale mechanisms with the macro-scale performance of materials with granular textures. In this model, the micro-scale is described by damage-elasto-plastic spring elements that represent the effective grain pair interactions decomposed into the so-called normal and tangential directions. Since the grain-pairs are variously oriented, the macro-scale response is obtained by integrating these interactions over the orientational space. Here we specialize the granular micromechanic model for UHP FRC by introducing a novel expression for the parameterized dissipation energy at the micro or the grain-pair scale. The newly introduced constitutive parameters are identified using experimental results for uniaxial extension and compression tests. The model is then applied to simulate the case of homogeneous compression, extension and shear to show the directional evolution of damage and plasticity and the consequent emergent anisotropy.

超高性能纤维增强混凝土(UHP FRC)自二十多年前问世以来一直得到蓬勃发展,人们对其应用的兴趣日益浓厚。这些先进材料的优点是它们克服了困扰传统混凝土的问题,这些问题包括残余强度低、抗拉强度低、裂缝控制和抗裂缝扩展能力差,从而导致钢筋腐蚀和剥落。本文的目的是提供一个基于颗粒细观力学的模型来描述UHP FRC材料的变形行为,因为它提供了一种将具有颗粒织构的材料的微观尺度机制与宏观尺度性能联系起来的稳健方法。在该模型中,微观尺度由损伤弹塑性弹簧单元来描述,这些弹簧单元代表了分解为所谓的法向和切向的有效晶粒对相互作用。由于颗粒对的取向不同,通过在取向空间上对这些相互作用进行积分得到宏观尺度的响应。本文通过引入一种新的微尺度或粒对尺度的参数化耗散能表达式,对超高压FRC的颗粒细观力学模型进行了细化。利用单轴拉伸和压缩试验结果确定了新引入的本构参数。将该模型应用于均匀压缩、拉伸和剪切情况下的数值模拟,揭示了损伤和塑性的方向性演化及其产生的各向异性。


Mechanics of Materials

Kirigami Beyond Tension: Expanding Kirigami’s Versatility via Shear Actuation

Nicolas A. Alderete, Barty Wardell, Horacio D. Espinosa

doi:10.1016/j.mechmat.2024.105024

超越张力的Kirigami:通过剪切驱动扩展Kirigami的多功能性

The potential of Kirigami-based metamaterials as versatile platforms in applications where shape-morphability is desired is presently well established. Interestingly, in-plane loading under simple tension has been the predominant actuation-of-choice, with other fundamental loadings (e.g., shear, torsion) being largely overlooked. In this work, we explore the instability landscape of a simple Kirigami motif under in-plane shear loading and demonstrate how the incorporation of shear actuation effectively augments both the design and output space of Kirigami-based metamaterials. The nonlinear response of Kirigami under shear is first elucidated parametrically via nonlinear Finite Element Analysis on a subset of geometrically asymmetric motifs. The interplay between cut layout and the bidirectional nature of in-plane shear enables a variegated bifurcation landscape that includes unusual inversions and sharp kinks in the bifurcation curves. The numerical analysis is complemented with experimental validation of the out-of-plane bifurcation curves of several cases of interest by means of shadow moiré and laser displacement sensing. Together with the experimental validation, a proof-of-concept demonstration of the applicability of Kirigami-shear metamaterials as multistate electro-mechanical switches is presented. Overall, our findings add a new dimension to an already rich design space, thus opening a vista of opportunities for multimodal programmable structures, particularly appealing in sensing and actuation applications.

基里伽米基超材料作为多功能平台的潜力目前已经很好地确立了。有趣的是,简单张力作用下的平面内载荷一直是主要的驱动选择,而其他基本载荷(如剪切、扭转)在很大程度上被忽视了。在这项工作中,我们探索了一个简单的基里伽米图案在面内剪切载荷下的不稳定景观,并展示了剪切驱动的结合如何有效地增加了基里伽米基超材料的设计和输出空间。本文首先通过对一组几何不对称模体的非线性有限元分析,参数化地阐明了基里伽米结构在剪切作用下的非线性响应。切割布局与平面内双向剪切特性之间的相互作用,形成了多样化的分岔景观,包括不寻常的反转和分岔曲线上的尖锐扭结。在数值分析的基础上,利用阴影位移和激光位移传感技术,对不同情况下的面外分岔曲线进行了实验验证。结合实验验证,提出了基里伽米剪切超材料作为多态机电开关适用性的概念验证。总的来说,我们的发现为已经丰富的设计空间增加了一个新的维度,从而为多模态可编程结构开辟了一个机会的前景,特别是在传感和驱动应用中。


International Journal of Plasticity

Strengthening complex concentrated alloy without ductility loss by 3D printed high-density coherent nanoparticles

Gang Qin, Qian Yu, Kaiping Yu, Yan Fang, Ruirun Chen, Zhiyuan Liang, Mingxin Huang

doi:10.1016/j.ijplas.2024.103987

3D打印高密度相干纳米颗粒增强复合浓缩合金而不损失延性

Metallic 3D printing enables fast fabrication of net-shaped components for broad engineering applications, yet it restrains the use of most mechanical processing methods for strengthening alloys, e.g. forging, rolling, etc. Here, we proposed a new strategy for enhancing the strength of 3D printed complex concentrated alloys without losing ductility. This strategy relies on the rapid cooling of 3D printing to achieve a supersaturation state that is beyond conventional casting. Then, spinodal decomposition via aging is exploited to introduce high-density coherent nanoparticles for strengthening. The proposed strategy is demonstrated in a 3D printed Cu-based complex concentrated alloy. The rapid solidification during printing strongly inhibits elemental diffusion, leading to a high supersaturation state. High-density nanoparticles with coherent interface and size of ∼7 nm are introduced into the 3D printed samples through spinodal decomposition via simple aging treatment. The strength of the 3D printed alloy is increased by 30% after aging with no ductility loss, leading to a strength-ductility combination superior to other Cu alloys. This strategy is readily applicable to other spinodal alloys fabricated by 3D printing for circumventing the strength-ductility trade-off dilemma.

金属3D打印可以快速制造网状部件,用于广泛的工程应用,但它限制了大多数机械加工方法用于强化合金的使用,例如锻造,轧制等。在此,我们提出了一种新的策略来提高3D打印复杂浓缩合金的强度而不失去延展性。这种策略依赖于3D打印的快速冷却,以达到超越传统铸造的过饱和状态。然后,利用时效的spinodal分解,引入高密度相干纳米颗粒进行强化。在3D打印的铜基复合浓缩合金中验证了所提出的策略。印刷过程中的快速凝固强烈地抑制了元素的扩散,导致高过饱和状态。通过简单时效处理,将具有相干界面、尺寸为~ 7 nm的高密度纳米颗粒引入到3D打印样品中。时效后,3D打印合金的强度提高了30%,且无延性损失,强度-延性组合优于其他Cu合金。该策略很容易适用于其他通过3D打印制造的spinodal合金,以避免强度-延性权衡的困境。


Thin-Walled Structures

Member Capacity of Cold-rolled Aluminium Alloy Channel Columns - Part I: Experimental Investigation

Ngoc Hieu Pham, Cao Hung Pham, Kim J.R. Rasmussen

doi:10.1016/j.tws.2024.111959

冷轧铝合金槽柱的构件承载力。第1部分:试验研究

Cold-rolled aluminium alloy sections have been recently introduced in Australia as newly developed thin-walled products. To fabricate these sections, the roll-forming process used in cold-formed steel production has been employed, which has proven to be more cost-effective than the conventional extrusion process. This paper describes a series of compression tests to investigate member buckling behaviour and ultimate strengths of cold-rolled aluminium alloy 5052-36 channel columns. Twenty-eight specimens of three commercially available sections (C10030, C25025 and C40030) were tested at the University of Sydney. Two configurations of end boundary conditions were specially designed to capture flexural, flexural-torsional and local-global interaction buckling failure modes. Prior to testing, initial geometric imperfections were measured using a laser scanning method, and flat/corner coupons were tested to determine compressive and tensile strengths of the aluminium alloy material. The experimental results are compared with ultimate column strength predictions by current Australian/New Zealand, North American and European design specifications for aluminium structures. Additionally, the test results provide data for calibration of finite element models of cold-rolled aluminium structural members for use in parametric and similar studies. A companion paper describes such parametric study and the derivation of new design guidelines for member buckling of cold-rolled aluminium channel columns based on the numerical parametric data and the experimental data presented herein.

冷轧铝合金型材作为新开发的薄壁产品最近在澳大利亚推出。为了制造这些截面,采用了冷弯型钢生产中使用的滚压成形工艺,这已被证明比传统的挤压工艺更具成本效益。本文介绍了冷轧铝合金5052-36槽形柱构件屈曲行为和极限强度的一系列压缩试验。在悉尼大学对三种市售断面(C10030、C25025和C40030)的28个标本进行了测试。针对弯曲、弯曲-扭转和局部-全局相互作用的屈曲破坏模式,设计了两种不同的端边界条件。在测试之前,使用激光扫描方法测量初始几何缺陷,并测试平/角片状材料以确定铝合金材料的抗压和抗拉强度。试验结果与当前澳大利亚/新西兰、北美和欧洲铝结构设计规范的极限柱强度预测进行了比较。此外,试验结果为冷轧铝结构构件有限元模型的校正提供了数据,用于参数化研究和类似研究。另一篇论文描述了这种参数化研究,并基于数值参数数据和本文提供的实验数据推导了冷轧铝槽柱构件屈曲的新设计准则。


Stretch-induced wrinkling of anisotropic hyperelastic thin films

Ping-Ping Chai, Yang Liu, Fan-Fan Wang

doi:10.1016/j.tws.2024.111961

各向异性超弹性薄膜的拉伸致皱

Thin films may experience wrinkling instability when two clamped ends are stretched uniaxially. For a fiber-reinforced anisotropic thin film, the wrinkling distributions and evolutions can be significantly affected by the fiber orientation and the anisotropic parameters. In this paper, we study the stretch-induced wrinkling of anisotropic thin films based on a uniformly-valid asymptotic plate equation for anisotropic materials derived from the three-dimensional field equations. A numerical model is established in COMSOL Multiphysics by virtue of the weak form of plate equations and by employing the Holzapfel-Gasser-Ogden model. The effects of fiber orientations and anisotropic parameters on wrinkling evolutions are unraveled from various case studies. In particular, we find that there exists a critical fiber orientation interval where the usual isola-center bifurcation will give way to the pitchfork bifurcation, and the associated amplitude against strain curve presents an N shape. A phase diagram for different bifurcation types is characterized as well. Our numerical model is validated by three-dimensional numerical simulations. It is expected that the results in this paper will offer useful insight into pattern formation in anisotropic soft materials.

当两个夹持端受到单轴拉伸时,薄膜可能会出现起皱不稳定性。对于纤维增强的各向异性薄膜,纤维取向和各向异性参数会显著影响皱纹的分布和演变。本文基于从三维场方程导出的各向异性材料均匀有效渐近板方程,研究了各向异性薄膜的拉伸诱导起皱。利用板方程的弱形式和 Holzapfel-Gasser-Ogden 模型,在 COMSOL Multiphysics 中建立了一个数值模型。通过各种案例研究,揭示了纤维取向和各向异性参数对起皱演变的影响。特别是,我们发现存在一个临界纤维取向区间,在该区间内,通常的等中心分叉将让位于叉形分叉,相关的振幅与应变曲线呈现 N 型。不同分叉类型的相图也具有相同的特征。三维数值模拟验证了我们的数值模型。预计本文的研究结果将为各向异性软材料中图案的形成提供有益的启示。


A novel design of an I-shape self-locked thin-walled system with mortise and tenon joints

Jianqiang Deng, Wanqi Zhao, Jingzhe Wang, Jiayu Li, Bowen Wu, Xueshun Li, Xiaobo Liu, Liming Chen, Tao Liu, Shaowei Zhu, Xin Pan

doi:10.1016/j.tws.2024.111966

一种新颖的带有榫卯连接的i形自锁薄壁系统设计

In this paper, an I-shaped self-locked thin-walled system (IST-SY) composed of I-shaped self-locked thin-walled structures (IST-STs), combining with the mortise & tenon joint (MTJ) principle originated from ancient China and the I-shaped thin-walled structure, was proposed to avoid the splashing of the structures. Then, the IST-ST was retrofitted according to the multi-stair MTJ principle to improve the energy absorption capacity. The loading response curve, deformation mode, and energy absorption of the IST-ST and retrofitted IST-STs (RIST-STs) were investigated systematically by combined experimental and numerical efforts. The results show that the IST-ST was particularly susceptible to unstable catastrophic collapses, characterized by multiple peaks in response curves, whereas the RIST-STs with an appropriate stair panel exhibit exceptionally high damage tolerance compared with the original one. The introduction of the stair panels that link to adjacent panels provides additional support to avoid buckling instability that causes catastrophic collapse, thus generating a more uniform plastic deformation distribution. It effectively curtails the initial high crushing resistance and makes the load more stable on the premise of energy absorption. To demonstrate the validity of the self-locked characteristic, flatwise crushing was also carried out on the proposed self-locked systems, which could successfully resist lateral splashing owing to the unique I-shaped section with the concave-convex feature. The proposed self-locked structures & system exhibit better energy absorption performance than the existing self-locked structures & systems, which was 128.11%, and 62.97% higher than the foam-filled bidirectional self-locked structures & system, respectively. This work paves a novel avenue for the design diversity of self-locked energy absorption systems.

本文结合源自中国古代的榫卯连接(MTJ)原理和工字钢薄壁结构,提出了一种由工字钢自锁薄壁结构(IST-STs)组成的工字钢自锁薄壁系统(IST-SY),以避免结构的飞溅。然后,根据多台阶MTJ原理对IST-ST进行改造,提高其吸能能力。采用实验与数值相结合的方法,系统地研究了IST-ST和改型IST-STs (list - sts)的加载响应曲线、变形模式和能量吸收。结果表明,IST-ST特别容易发生不稳定的灾难性倒塌,其特征是响应曲线出现多个峰,而与原始楼梯面板相比,具有适当楼梯面板的IST-ST具有异常高的损伤容差。楼梯面板与相邻面板的连接提供了额外的支撑,以避免导致灾难性倒塌的屈曲不稳定,从而产生更均匀的塑性变形分布。它有效地限制了初始的高破碎阻力,在吸收能量的前提下使载荷更加稳定。为了证明自锁特性的有效性,还对所提出的自锁系统进行了平面破碎,由于其独特的具有凹凸特征的i型截面,可以成功地抵抗侧向飞溅。所提出的自锁结构和体系的吸能性能比现有的自锁结构和体系分别提高128.11%和62.97%,比泡沫填充的双向自锁结构和体系的吸能性能要好。本研究为自锁吸能系统的设计多样性开辟了新的途径。


Nonlinear Combination Resonance Analysis of Parametric-Forced Excitation for An Axially Moving Piezoelectric Rectangular Thin Plate in Thermal- Electromechanical Coupling Field

Zhe LI, Yi LI, HongMiao YU, YuDa HU

doi:10.1016/j.tws.2024.111941

热-机电耦合场中轴向移动压电矩形薄板参数强制激励的非线性组合共振分析

In this paper, the combination resonance of parametric-forced excitation characteristics for an axially moving rectangular piezoelectric plate under a thermal-electromechanical field is studied. Based on Kirchhoff-Love plate theory and Von Karman theory, the transverse vibration governing equations are derived from Hamilton's principle. The equations are discretized to ordinary differential equations by the Galerkin method. Then, the multiple scales method is applied to solve the system combination resonance equation, two different resonance states and corresponding amplitude-frequency response equations are obtained by eliminating the secular term respectively. Additionally, the stability of the steady-state responses is analyzed by Lyapunov stability. Based on the numerical analysis, the influence of axial velocity, external voltage, central temperature difference, structural damping, and other parameters on nonlinear combination resonance response are investigated. The effect of parameter variation on period-doubling bifurcation and the chaotic motion of the system are also discussed by the system global bifurcation diagram.

本文研究了热-机电场作用下轴向运动矩形压电板的参数强制激励组合共振特性。基于Kirchhoff-Love板理论和Von Karman理论,根据Hamilton原理推导出横向振动控制方程。用伽辽金方法将方程离散为常微分方程。然后,采用多尺度法求解系统组合共振方程,分别通过消去长期项得到两种不同的共振状态和相应的幅频响应方程。此外,利用李雅普诺夫稳定性分析了稳态响应的稳定性。在数值分析的基础上,研究了轴向速度、外电压、中心温差、结构阻尼等参数对非线性组合共振响应的影响。通过系统全局分岔图,讨论了参数变化对系统倍周期分岔和混沌运动的影响。


Modeling and vibration analysis of bolted composite conical-conical shells with flanges

Xiaofeng Liu, Wei Sun, Honghao Liu, Hongwei Ma, Dongxu Du, Hui Li

doi:10.1016/j.tws.2024.111955

带法兰螺栓复合锥形-锥形壳的建模与振动分析

This paper proposes a general semi-analytical modeling method of bolted composite conical-conical shells with flanges based on the first-order shear deformation theory. The coupling connections between conical shells and flanges are achieved by using the penalty function method. A bolted joint model that considers the non-uniform distribution of interface pressure is proposed, which can efficiently simulate any number of bolt connections between flanges and boundaries and between flanges and flanges. The correctness and effectiveness of the proposed modeling method are confirmed through step-by-step comparisons with finite element analysis and experimental testing. Then, the influence of various parameters on the frequency trajectories and modal shapes of bolted composite conical-conical shells with flanges is analyzed, with a particular focus on frequency veering and modal coupling vibration behaviors in these structures. The analyses indicate that the proposed modeling method can flexibly adjust structural geometric parameters, material parameters, bolt parameters, fiber layer parameters, and so on, which can efficiently guide the dynamic design of bolted composite conical shell structures with flanges.

提出了一种基于一阶剪切变形理论的带法兰螺栓复合锥-锥壳半解析建模方法。采用罚函数法实现了锥壳与法兰的耦合连接。提出了一种考虑界面压力非均匀分布的螺栓连接模型,可以有效地模拟任意数量的法兰与边界之间以及法兰与法兰之间的螺栓连接。通过与有限元分析和实验测试的逐步对比,验证了所提建模方法的正确性和有效性。然后,分析了各参数对带法兰螺栓连接的复合锥-锥壳的频率轨迹和模态振型的影响,重点研究了这些结构的频率转向和模态耦合振动行为。分析表明,所提出的建模方法可以灵活调整结构几何参数、材料参数、螺栓参数、纤维层参数等,能够有效指导带法兰螺栓复合锥形壳结构的动态设计。


Nonlinear free vibration analysis of an elastically supported annular plate in nonuniform induced magnetic field

Haoran Xu, Yuda Hu

doi:10.1016/j.tws.2024.111958

非均匀感应磁场下弹性支承环形板的非线性自由振动分析

The aim of this article is to investigate nonlinear free vibration and electromagnetic mechanical behavior of a conductive annular plate with elastic boundary in induced non-uniform magnetic field. On basis of magneto-elastic vibration control equation of conductive plates, displacement solution for plates under complex elastic constraints is first solved, and the axisymmetric nonlinear differential equation for plate is derived by combining Galerkin method. Introducing the multi-scale method to solve the differential equation of elastic boundary plate in induced magnetic field to achieve the analytical expression for natural frequency including current and elastic stiffness terms, and the variation of system singularity is analyzed through stability discriminant. Through numerical method, the nonlinear frequency variation curves, electromagnetic characteristic curves, stability area and phase trajectory graphics of singularities with various control parameters are presented. The result accuracy verification was also conducted in comparison to relevant literature and numerical solutions. The interesting and key findings revealed that, under internal diameter clamped and outer diameter elastically supported boundary, the variation of natural frequency with current, time, the nonlinear soft and hard characteristics are completely opposite to rest two boundaries. The elastic stiffness may significantly increase natural frequency, but does not change the soft or hard characteristics of system. With influence of elastic boundaries, the distribution of electromagnetic force and torque in radial direction of plate becomes quite complex under non-uniform magnetic field. In addition, wire current may change the type of system singularity as current increases.

本文研究了具有弹性边界的导电环形板在感应非均匀磁场中的非线性自由振动和电磁力学行为。在导电板的磁弹性振动控制方程的基础上,首先求解了复杂弹性约束下导电板的位移解,并结合伽辽金法导出了导电板的轴对称非线性微分方程。引入多尺度法求解感应磁场下弹性边界板的微分方程,得到固有频率包括电流项和弹性刚度项的解析表达式,并通过稳定性判别法分析了系统奇点的变化。通过数值方法,给出了不同控制参数下奇异点的非线性频率变化曲线、电磁特性曲线、稳定面积和相位轨迹图。并与相关文献和数值解进行对比,验证结果的准确性。有趣的和关键的发现是,在内径夹紧和外径弹性支撑边界下,固有频率随电流、时间的变化,非线性软硬特性与静边界完全相反。弹性刚度可以显著提高系统的固有频率,但不会改变系统的软、硬特性。在非均匀磁场作用下,受弹性边界的影响,电磁力和转矩在板的径向分布变得相当复杂。此外,导线电流可能会随着电流的增加而改变系统奇点的类型。


Member Capacity of Cold-rolled Aluminium Alloy Channel Columns - Part II: Numerical Investigation and Design

Ngoc Hieu Pham, Cao Hung Pham, Kim J.R. Rasmussen

doi:10.1016/j.tws.2024.111960

冷轧铝合金槽柱的构件容量。第2部分:数值研究和设计

The paper first presents the development of detailed finite element (FE) models for investigating the member capacity of cold-rolled aluminium alloy 5052-36 channel columns. The numerical non-linear FE models are developed using the commercial FE software package ABAQUS to simulate laboratory experiments and calibrated against the test results. The experimental program was performed by the authors at the University of Sydney and the detailed test results are fully described in a companion paper. The calibrated numerical FE models with actual mechanical properties and measured geometric imperfections in analyses accurately predict the experimental results and behaviours, including flexural and flexural-torsional buckling as well as local-global interaction buckling failure modes. A parametric study is subsequently performed to extend the data range by varying cross-section dimensions and member lengths. The effects of loading eccentricity positions and initial geometric imperfections are also considered in the parametric study. The experimental and numerical results are compared with design strength predictions from current Australian/New Zealand, American and European specifications for aluminium structures in the companion paper. In this paper, the Direct Strength Method (DSM) for the design of compression members as per the Australian/New Zealand standard AS/NZS 4600 for cold-formed steel structures is adopted for comparison. The DSM design rules for cold-formed steel compression members are found to provide more accurate predictions than those of current specifications for aluminium structures and therefore used to propose improved design equations for cold-rolled aluminium alloy columns. Finally, a reliability analysis is performed to evaluate the safety level of current design specifications and the proposed design rules.

本文首先介绍了用于研究5052-36型冷轧铝合金槽钢柱构件承载力的详细有限元模型的发展。利用商业有限元软件包ABAQUS建立了数值非线性有限元模型,模拟实验室实验,并根据试验结果进行校准。实验程序是由作者在悉尼大学进行的,详细的测试结果在一篇配套论文中有完整的描述。校正后的数值有限元模型具有实际力学性能和分析中测量的几何缺陷,可以准确预测实验结果和行为,包括弯曲、弯曲-扭转屈曲以及局部-全局相互作用的屈曲破坏模式。随后进行参数化研究,通过改变截面尺寸和构件长度来扩展数据范围。在参数化研究中还考虑了加载偏心位置和初始几何缺陷的影响。实验和数值结果与本文中现行澳大利亚/新西兰、美国和欧洲铝结构规范的设计强度预测进行了比较。本文采用澳大利亚/新西兰标准as /NZS 4600对冷弯型钢结构进行压缩构件设计的直接强度法(DSM)进行比较。发现冷弯型钢压缩构件DSM设计规则比现行铝结构规范提供更准确的预测,因此用于提出改进的冷轧铝合金柱设计方程。最后,进行了可靠性分析,以评估当前设计规范和建议设计规则的安全水平。


Application of physics-informed machine learning methods in buckling design of axially compressed cylindrical shells

Fang Liu, Haofeng Chen, Jie Yang, Xiaoxiao Wang

doi:10.1016/j.tws.2024.111963

基于物理的机器学习方法在轴向压缩圆柱壳屈曲设计中的应用

A physics-informed artificial neural network (ANN) is developed for the buckling design of cylindrical shells under axial compression, and two strategies are applied to incorporate physical knowledge into the ANN model. One strategy is to introduce physics-informed features derived from the local reduced stiffness method (LRSM) as additional input features. The other strategy is to incorporate physical constraints based on elastic buckling theory into the loss function of ANN. The accuracy of the proposed model is verified using a buckling dataset of metal and non-metal cylindrical shells. Results demonstrate that the proposed physics-informed ANN model with four hidden layers achieves better predictive performance than pure data-driven random forest (RF), support vector machine (SVM) and ANN. Furthermore, the physics-informed model could predict moderately conservative buckling loads with a design factor of 1.25.

针对轴压下圆柱壳屈曲设计问题,提出了一种基于物理信息的人工神经网络(ANN),并采用两种策略将物理知识融入到ANN模型中。一种策略是引入从局部降刚度法(LRSM)中导出的物理信息特征作为附加输入特征。另一种策略是将基于弹性屈曲理论的物理约束融入到人工神经网络的损失函数中。利用金属和非金属圆柱壳的屈曲数据验证了该模型的准确性。结果表明,与纯数据驱动随机森林(RF)、支持向量机(SVM)和人工神经网络相比,该模型具有更好的预测性能。此外,考虑物理因素的模型可以预测适度保守的屈曲载荷,设计系数为1.25。




来源:复合材料力学仿真Composites FEM
ACTMechanicalSystemAbaqusMAGNET振动非线性电磁力ECAD铸造电场理论材料螺栓
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首次发布时间:2024-11-14
最近编辑:9天前
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【新文速递】2024年4月16日固体力学SCI期刊最新文章

今日更新:International Journal of Plasticity 1 篇,Thin-Walled Structures 1 篇International Journal of PlasticityMicromechanism of strength and damage trade-off in second-phase reinforced alloy by strain gradient plasticity theoryLi Li, Jing Peng, Sisi Tang, Qihong Fang, Yueguang Weidoi:10.1016/j.ijplas.2024.103970应变梯度塑性理论研究第二相增强合金强度与损伤取舍的微观机制The strength and damage are mutually exclusive in most alloys. It is still a challenge to understand the role of microstructural features in affecting strength and damage tolerance simultaneously. In this study, we provide a general approach to unveil the micromechanism of strength and damage trade-off in second-phase reinforced alloy. Concretely, a microstructure-based constitutive model incorporating the strain gradient plasticity theory is developed to evaluate the overall mechanical behavior and local deformation behavior of particle-reinforced alloys by finite element simulations. The strain gradient effect exacerbates the non-uniform stress distribution, particularly enhancing the local stress level around the particle-matrix interface, thereby improving the total strain hardening of the alloys. Importantly, the strain gradient effect can significantly expand regions with local stress levels surpassing the critical stress for microcrack nucleation, ultimately leading to damage initiation and failure. This elucidates the micromechanism underpinning the trade-off between strength and damage. By revealing the competitive relationship between local stress concentration and microcrack nucleation stress, the comprehensive effects of particle size and volume fraction on the strength, strain hardening and damage tolerance are quantitatively predicted. It is recommended to adjust the particle volume fraction based on reducing the particle size to obtain the desired properties. The present work discerns the inherent origin of the strength-damage trade-off in particle-reinforced alloy and sheds light on the role of the particle size and volume fraction on the strength and damage tolerance, which can offer valuable guidance for developing high-performance particle-reinforced materials.在大多数合金中,强度和损伤是相互排斥的。如何理解微观结构特征在同时影响强度和损伤容限中的作用仍然是一个挑战。本研究为揭示第二相增强合金强度与损伤权衡的微观机制提供了一种通用方法。具体而言,结合应变梯度塑性理论,建立了基于微观组织的本构模型,通过有限元模拟评估颗粒增强合金的整体力学行为和局部变形行为。应变梯度效应加剧了应力分布的不均匀性,特别是提高了颗粒-基体界面附近的局部应力水平,从而提高了合金的总应变硬化。重要的是,应变梯度效应可以显著扩大局部应力水平超过微裂纹成核临界应力的区域,最终导致损伤的发生和破坏。这阐明了支撑强度和损伤之间权衡的微观机制。通过揭示局部应力集中与微裂纹形核应力之间的竞争关系,定量预测了颗粒尺寸和体积分数对强度、应变硬化和损伤容限的综合影响。建议在减小粒径的基础上调整颗粒体积分数,以获得所需的性能。本研究揭示了颗粒增强合金强度-损伤权衡的内在根源,揭示了颗粒尺寸和体积分数对强度和损伤容限的影响,为高性能颗粒增强材料的开发提供了有价值的指导。Thin-Walled StructuresExperimental and numerical study on energy absorption performance of truncated origami materialsWei Qiang, Yvonne Durandet, Xin Zhang, Guoxing Ludoi:10.1016/j.tws.2024.111911截尾折纸材料吸能性能的实验与数值研究In this study, a truncated origami structure, originated from the Miura-ori structure, was designed. The compressive behaviours of this structure subjected to x2-direction (in-plane) and x3-direction (out-of-plane) compression were studied both experimentally and numerically. The structure with a smaller truncated ratio value, e, was more similar to a dense solid. Representative specimens of the Miura-ori and the truncated origami designs were fabricated and tested under both quasi-static and dynamic (v = 7 m/s) conditions. Compared to the Miura-ori structure, the truncated origami showed higher specific energy absorption (SEA) and less load drop between the initial peak force and mean crushing force. In both loading directions, the SEA increased as the truncated ratio decreased for the truncated origami specimens, which was comparable under both quasi-static and dynamic loading. The truncated origami was extrapolated to a numerical model with 555 cells to mimic a block of material, and the effects of truncated ratio and loading velocity were investigated. As the e decreased, the deformation mode gradually changed from rigid folding and progressive deformation to plate buckling mode under quasi-static compression. This change was accompanied by an increase in both SEA and overall strength. The truncated origami exhibited the best energy absorption performance when e = 0.6. Under quasi-static compression in the x2- and x3-direction, the SEA of truncated origami is 3.2 and 1.6 times that of Miura-ori metamaterial, respectively. The truncated origami materials with a truncated ratio of 0.8 remained velocity-insensitive up to 25m/s and displayed similar strength and deformation modes as under quasi-static loading. At a speed of 50 m/s the deformation became more localized, and the SEA increased significantly. The auxetic and expansion behaviours were significantly diminished under higher impact velocities.在本研究中,设计了一种源于三浦织结构的截尾折纸结构。实验和数值研究了该结构在平面内和平面外两种方向的压缩特性。截断比值e越小,结构越接近致密固体。在准静态和动态(v = 7 m/s)条件下,制作了具有代表性的Miura-ori折纸和截尾折纸样品并进行了测试。与Miura-ori结构相比,截断折纸具有更高的比能吸收(SEA)和更小的初始峰值力与平均破碎力之间的载荷差。在两个加载方向上,截尾折纸试样的SEA随截尾比的减小而增大,在准静态和动态加载下具有可比性。将截尾折纸外推为555单元的数值模型,模拟材料块,研究截尾比和加载速度对折纸的影响。随着e的减小,变形模式逐渐由刚性折叠渐进式变形转变为准静态压缩下的板屈曲模式。这一变化伴随着SEA和整体实力的增加。截尾折纸在e = 0.6时吸能性能最佳。在准静态压缩下,截尾折纸的SEA分别是Miura-ori超材料的3.2倍和1.6倍。截断比为0.8的截尾折纸材料在25m/s内保持速度不敏感,并表现出与准静态加载相似的强度和变形模式。在50 m/s速度下,变形局部化,SEA明显增大。在较高的冲击速度下,合金的形变和膨胀行为明显减弱。来源:复合材料力学仿真Composites FEM

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