【新文速递】2024年5月4日固体力学SCI期刊最新文章

 

今日更新：Journal of the Mechanics and Physics of Solids 1 篇，Mechanics of Materials 1 篇，Thin-Walled Structures 3 篇

Journal of the Mechanics and Physics of Solids

I too I 2 : A new class of hyperelastic isotropic incompressible models based solely on the second invariant

Ellen Kuhl, Alain Goriely

doi:10.1016/j.jmps.2024.105670

I too I 2:一类新的基于第二不变量的超弹性各向同性不可压缩模型

In contemporary elasticity theory, the strain–energy function predominantly relies on the first invariant, I 1 of the deformation tensor; a practice that has been influenced by models derived from rubber elasticity. However, this approach may not fully capture the complexities of materials exhibiting pronounced shear deformations, such as very soft biological tissues. Here, we explore the implications and potential benefits of constitutive models where the strain–energy function is exclusively a function of the second invariant, I 2 . By shifting the focus towards I 2 , we aim to address the limitations of current models in accurately describing shear-dominated behaviors and to provide a more comprehensive understanding of material responses, particularly for materials that do not conform to the assumptions underlying I 1 -centric theories. Through theoretical musings, data analysis, and automated model discovery, we investigate the feasibility of this approach and its consequences for predicting material behavior under various loading conditions. We show that the so-called “second-invariant materials” conforming to I 2 -only have interesting properties that are found in biological tissues and are fundamentally different from the traditional “first-invariant materials”.

在当代弹性理论中，应变-能函数主要依赖于变形张量的第一不变量I 1;受橡胶弹性模型影响的实践。然而，这种方法可能无法完全捕获具有明显剪切变形的材料的复杂性，例如非常柔软的生物组织。在这里，我们探讨了应变-能量函数完全是第二个不变量i2的函数的本构模型的含义和潜在好处。通过将焦点转移到i2，我们的目标是解决当前模型在准确描述剪切主导行为方面的局限性，并提供对材料响应的更全面理解，特别是对于不符合i1中心理论假设的材料。通过理论思考、数据分析和自动模型发现，我们研究了这种方法的可行性及其在各种加载条件下预测材料行为的后果。我们表明，符合i2 -only的所谓“第二不变材料”具有在生物组织中发现的有趣性质，并且与传统的“第一不变材料”有根本不同。

Mechanics of Materials

A tensorial energy-release-rate based anisotropic damage-plasticity model for concrete

Liang Xue, Xiaodan Ren

doi:10.1016/j.mechmat.2024.105025

基于张拉能量释放率的混凝土各向异性损伤塑性模型

This paper proposes an anisotropic damage model for concrete to capture its plasticity and damage behavior effectively. Utilizing the framework of continuum damage mechanics, the model considers the influence of plastic Helmholtz free energy on damage evolution. This approach explicitly deduces damage-related thermodynamic forces without resorting to assumptions such as strain equivalence or energy equivalence. The proposed model employs tensile and compressive damage tensors to describe the development of anisotropic damage in concrete. The solution for plastic strain utilizes the empirical plasticity model. Furthermore, a unified evolutionary criterion for isotropic and anisotropic damage is also established, incorporating damage yield functions and orthogonal flow laws. Numerical simulations are conducted to validate the model’s ability to reproduce typical nonlinear behaviors of concrete structures under various load conditions.

为了有效地反映混凝土的塑性和损伤行为，提出了混凝土的各向异性损伤模型。该模型采用连续损伤力学的框架，考虑了塑性亥姆霍兹自由能对损伤演化的影响。这种方法明确地推导出与损伤相关的热力学力，而不需要求助于诸如应变等效或能量等效之类的假设。该模型采用拉伸和压缩损伤张量来描述混凝土各向异性损伤的发展。塑性应变的求解采用经验塑性模型。并结合损伤屈服函数和正交流动规律，建立了各向同性和各向异性损伤的统一演化准则。通过数值模拟验证了该模型在不同荷载条件下再现典型混凝土结构非线性行为的能力。

Thin-Walled Structures

Bandgap tunability and programmability of four-leaf clover shaped elastic metastructures

Zan Deng, Yingli Li, Guangjun Gao

doi:10.1016/j.tws.2024.111965

四叶草型弹性元结构的带隙可调性和可编程性

This paper studies the propagation of elastic waves in a four-leaf clover shaped elastic metastructure (EM), which consists of periodically distributed solid blocks connected by slender beams. The bandgap structure and vibrational transmittance of four-leaf clover shaped EM plates were examined using two-dimensional (2D) and three-dimensional (3D) solid elements. The comparison of elastic wave propagation experiments and numerical transmittance attenuation analysis shows excellent consistency and efficient wave regulation. Based on the experimentally validated model, the effect of structural parameters on the bandgap distribution is explored. It is found that the bandgap frequency can be lowered by up to 50% and widened by 22% by adjusting structural parameters, providing useful guidance for parameter settings to lower or widen the low-frequency bandgap. Finally, a programmable EM plate capable of guiding elastic wave propagation is proposed, which has the advantages of convenient adjustment and reliable structure, altering the bandgap from ‘‘on’’ to ‘‘off’’ by adjusting the distribution of the local resonators in the unit cell. Numerical demonstrations and experimental verifications are further carried out, illustrating that the proposed EM plate is capable of highly tuning elastic wave propagation. The results of the study indicate that the four-leaf clover shaped EM has a lower and wider bandgap adjustment range, which can realize waveguide control in a broadband range. The current findings provide important insights for the design of alternative devices such as vibration isolators, beams, and plates.

本文研究了弹性波在四叶草型弹性元结构中的传播。四叶草型弹性元结构是由细长梁连接的周期性分布的实心块组成的。采用二维(2D)和三维(3D)实体单元研究了四叶草型电磁板的带隙结构和振动透过率。弹性波传播实验与透射率衰减数值分析的对比表明，该方法具有良好的一致性和有效的调波效果。基于实验验证的模型，探讨了结构参数对带隙分布的影响。研究发现，通过调整结构参数，带隙频率可降低50%，宽度可达22%，为降低或扩大低频带隙的参数设置提供了有用的指导。最后，提出了一种可编程的引导弹性波传播的电磁板，该板具有调节方便、结构可靠等优点，可通过调节单元胞内局部谐振腔的分布来改变带隙从“开”到“关”。进一步进行了数值演示和实验验证，表明所提出的电磁板具有高调谐弹性波传播的能力。研究结果表明，四叶草型电磁具有更低、更宽的带隙调节范围，可以实现宽带范围内的波导控制。目前的研究结果为诸如隔振器、梁和板等替代装置的设计提供了重要的见解。

Fatigue behaviour and life prediction of self-piercing riveted joints in DP590/AA5754 dissimilar sheets

Yue Zhang, Jiachuan Jiang, Tao Wang, Bei Lei, Changyou Xu, Changhui Liao, Jianbiao Peng

doi:10.1016/j.tws.2024.111971

DP590/AA5754异种薄板自穿铆接接头疲劳行为及寿命预测

This paper investigates the fatigue properties of self-piercing riveted joints made by DP590 steel and AA5754 aluminium alloy. The fatigue failure mechanism and fatigue fretting mechanism of the joint were well revealed by analysing the microstructure features of fracture surfaces of sheets and rivets as well as viewing and measuring the distribution and chemical composition of fretting debris. The fatigue life of the joint was also predicted based on the stress intensity factor of the kinked crack of the lower sheet. The results confirmed that two failure modes occurred during fatigue: lower sheet fracture and rivet fracture. During the fatigue failure, cracks appeared in both the lower sheet and the rivets, indicating a competitive relationship between the propagation of cracks in the lower sheet and the rivets. In the range of 40% and 50% load level, fatigue crack propagation of the lower sheet is dominant and fracture failure of the lower sheet occurs. Rivet fatigue crack propagation has a significant advantage in the 60% load range and rivet fracture failure often occurs. It was found that the fatigue failure of the lower sheet is mainly influenced by the main crack, which produces two different morphological sections. Fretting wear of the contact surface was the source of crack initiation, and the fretting debris promoted crack initiation and propagation. Cracks propagate along the width and thickness of the plate, as well as the thickness of the rivet neck. The stress intensity factor range can properly predict the fatigue life of joints.

研究了DP590钢与AA5754铝合金自穿铆接接头的疲劳性能。通过分析板料和铆钉断口的微观组织特征，观察和测量微动碎屑的分布和化学成分，较好地揭示了接头的疲劳破坏机理和疲劳微动机理。根据下板弯曲裂纹的应力强度因子对接头的疲劳寿命进行了预测。结果表明，疲劳过程中存在两种破坏模式:下板断裂和铆钉断裂。疲劳破坏过程中，下板裂纹和铆钉裂纹同时出现，说明下板裂纹与铆钉裂纹的扩展存在竞争关系。在40%和50%载荷水平范围内，下板疲劳裂纹扩展为主，下板发生断裂破坏。在60%载荷范围内，铆钉具有明显的疲劳裂纹扩展优势，铆钉经常发生断裂破坏。结果表明，下板的疲劳破坏主要受主裂纹的影响，主裂纹产生了两种不同的形态断面。接触表面的微动磨损是裂纹萌生的根源，微动碎屑促进裂纹萌生和扩展。裂纹沿板的宽度和厚度以及铆钉颈的厚度传播。应力强度因子范围能较好地预测接头的疲劳寿命。

The axially-loaded behaviours of Schwarz Primitive (SP)-based structures: an experimental and DEM study

Hao Fu, Sakdirat Kaewunruen

doi:10.1016/j.tws.2024.111973

基于Schwarz Primitive (SP)结构的轴向载荷行为:实验和DEM研究

This study delves into the axial responses of Schwarz Primitive (SP) structures. Emphasising on bearing capacity, force distribution, cracking phenomena, load-displacement curve and energy absorption. Discrete element method (DEM) is adopted to analyse the axial load-bearing behaviour and fracture mechanics of Main SP and Secondary SP structures under various unit cell configurations after validated by experimental tests. The results indicates that despite sharing the same 1/8th cell structure, the axially-loaded behaviours of the Main SP and Secondary SP structures are not identical, particularly in scenarios involving a large unit cell size and a small number of unit cells. The Main SP structures display an axial load-bearing behaviour that is largely unaffected by variations in the number of unit cells along the x and y axes, while Secondary SP structures show a more pronounced improvement in average strength and energy absorption capacity when the number of unit cells increases. Main SP structures offer superior axial load-bearing capabilities and energy absorption efficiency, which is a significant consideration for their application in scenarios demanding high structural integrity. This distinction underlines the importance of tailored design and selection of SP configurations based on specific engineering requirements.

本研究探讨了Schwarz Primitive (SP)结构的轴向响应。强调承载力、力分布、开裂现象、荷载-位移曲线和能量吸收。采用离散元法(DEM)对不同单元格形下主SP和次SP结构的轴向承载性能和断裂力学进行了分析，并进行了试验验证。结果表明，尽管具有相同的1/8胞结构，但主SP结构和次级SP结构的轴向载荷行为并不相同，特别是在涉及大胞尺寸和小胞数量的情况下。主SP结构表现出轴向承载性能，这在很大程度上不受沿x和y轴的单元胞数变化的影响，而次SP结构在平均强度和能量吸收能力方面表现出更明显的改善，当单元胞数增加时。主要SP结构具有优越的轴向承载能力和能量吸收效率，这是其在要求高结构完整性的场景中应用的重要考虑因素。这种区别强调了根据特定工程要求定制设计和选择SP配置的重要性。