【新文速递】2024年9月27日固体力学SCI期刊最新文章

今日更新：International Journal of Solids and Structures 1 篇，Journal of the Mechanics and Physics of Solids 1 篇，Mechanics of Materials 1 篇，Thin-Walled Structures 1 篇International Journal of Solids and StructuresDoes static friction information predict the onset of sliding for soft material?Huixin Wei, Zhiyong Wang, Xinhao Tu, Xuanshi Cheng, Linan Li, Shibin Wang, Chuanwei Lidoi:10.1016/j.ijsolstr.2024.113087静摩擦信息能否预测软质材料滑动的开始?Friction behavior between soft and hard materials has long been a question of great interest in the fields of artificial joints, human skin contact, robotic grippers, and others. In this study, we presented a combination of theoretical and experimental analyses to investigate the friction behavior of soft materials. Using some geometric and stick–slip features in the early stage of static friction, the friction property of the interface between a soft material and a hard material is determined. Moreover, the onset of slip, the threshold force at which a friction interface begins to slide, is also predicted by a theoretical model. The predictive ability of this model may provide insights for improving interaction property recognition, as well as for developing fine tactile feedback and dexterous operation of robotic grasping.软硬材料之间的摩擦行为长期以来一直是人工关节、人体皮肤接触、机器人抓手等领域非常感兴趣的问题。在这项研究中，我们提出了理论和实验相结合的分析来研究软材料的摩擦行为。利用静摩擦初期的一些几何特征和粘滑特征，确定了软、硬材料界面的摩擦性能。此外，滑移起始力，即摩擦界面开始滑动的阈值，也可以通过理论模型来预测。该模型的预测能力可为改进交互特性识别，以及开发精细触觉反馈和机器人抓取灵巧操作提供见解。Journal of the Mechanics and Physics of SolidsHyperelastic constitutive relations for porous materials with initial stressMengru Zhang, Weiting Chen, Xianfu Huang, Quanzi Yuan, Ya-Pu Zhaodoi:10.1016/j.jmps.2024.105886具有初始应力的多孔材料的超弹性本构关系Initial stress is widely observed in porous materials. However, its constitutive theory remains unknown due to the lack of a framework for modeling the interactions between initial stress and porosity. In this study, we construct the porous hyperelastic constitutive model with arbitrary initial stresses through the multiplicative decomposition approach. Based on the compression experiment of shale samples, the parameters in the constitutive equation are determined. Then, the explicit equations of in-plane elastic coefficients are proposed by linearizing the finite deformation formulation. The influences brought by the coexistence of initial stresses and porosity on these coefficients are revealed. Later, comparative analyses of the linearized equations between the present model, the initially-stressed models without pores, the Biot poroelasticity, and the porous hyperelastic model without initial stress are conducted to illustrate the performances of the two ingredients. As a specific example, we investigate the variation of pore sizes under external pressures and initial stresses since changes in pore sizes during deformation are crucial for understanding the accumulation and migration of shale oil and gas. The newly proposed model provides the first initially stressed porous hyperelasticity (ISPH), which is suitable for describing the finite deformation behavior of solid materials with large porosity and significant initial stress simultaneously.在多孔材料中广泛观察到初始应力。然而，由于缺乏一个框架来模拟初始应力和孔隙度之间的相互作用，其本构理论仍然未知。本文采用乘法分解方法，建立了具有任意初始应力的多孔超弹性本构模型。通过对页岩试样的压缩实验，确定了本构方程中的参数。然后，将有限变形公式线性化，建立了平面内弹性系数的显式方程。揭示了初始应力和孔隙度共存对这些系数的影响。然后，将该模型与无孔隙初始应力模型、Biot孔隙弹性模型和无初始应力的多孔超弹性模型的线性化方程进行对比分析，以说明两种成分的性能。作为一个具体的例子，我们研究了外部压力和初始应力下孔隙大小的变化，因为变形过程中孔隙大小的变化对于理解页岩油气的聚集和运移至关重要。该模型提供了第一初始应力多孔超弹性模型(ISPH)，适用于描述大孔隙率和显著初始应力同时存在的固体材料的有限变形行为。Mechanics of MaterialsQuantification of elastic incompatibilities at triple junctions via physics-based surrogate modelsAaditya Rau, Christopher Schuh, Raúl Radovitzkydoi:10.1016/j.mechmat.2024.105163通过基于物理的替代模型量化三联点的弹性不相容Stresses resulting from elastic incompatibilities at grain boundaries have long been known to drive the premature failure and loss of desirable macroscopic properties in polycrystalline materials. In this work, we employ machine learning to create a surrogate model that furnishes a functional relationship between grain boundary configurational data and metrics of incompatibility. A planar triple junction geometry composed of cubic grains rotated about their [001] axis was adopted as the grain boundary model. High-fidelity finite element simulations of this triple junction under hydrostatic extension were used to generate a synthetic dataset for training the surrogate model. A set of J integrals computed around microcracks placed along the triple junction boundaries were used to quantify the elastic incompatibilities between the grains. Using the grain rotation angles and J integrals as the feature and label data respectively, a multi-layer perceptron network was trained using the synthetic data produced with the physics-based model. We demonstrate that the network trained using data from the physics-based model establishes an accurate functional dependence between the triple junction angles and the J integrals that enables direct and fast evaluation. We use the surrogate model to efficiently sweep the configuration space and create contour maps of the largest stress intensification at the triple junction as a function of the grain rotation angles. Furthermore, we show that the analytical properties of the surrogate model can be utilized to identify the most and least compatible triple junction configurations via optimization.长期以来晶界弹性不相容所产生的应力会导致多晶材料过早失效并丧失理想的宏观特性。在这项工作中，我们利用机器学习创建了一个替代模型，该模型提供了晶界构型数据与不相容性指标之间的函数关系。晶界模型采用了由围绕 [001] 轴旋转的立方晶粒组成的平面三结点几何体。在流体静力学延伸条件下，对该三交界处进行高保真有限元模拟，生成用于训练代用模型的合成数据集。沿三重交界处的微裂缝周围计算的一组 J 积分用于量化晶粒之间的弹性不相容性。将晶粒旋转角度和 J 积分分别作为特征数据和标签数据，使用基于物理模型生成的合成数据训练多层感知器网络。我们证明，使用基于物理模型的数据训练的网络在三重交界角和 J 积分之间建立了精确的函数关系，从而可以进行直接和快速的评估。我们利用代用模型有效地扫描了构型空间，并绘制出了三重交界处最大应力增强与晶粒旋转角函数关系的等高线图。此外，我们还展示了代用模型的分析特性可用于通过优化确定最兼容和最不兼容的三重连接配置。Thin-Walled StructuresMorphogenesis Analysis of Icosahedral and Prismatic Tensegrity ModulesXinran Wang, Zhihong Zhang, Hai Liu, Zhenhua Wang, Mingshan Zhangdoi:10.1016/j.tws.2024.112500二十面体和棱柱张拉整体模的形态发生分析Morphogenesis is a critical aspect of tensegrity system design. This paper explores icosahedral and prismatic tensegrity modules' pattern formation and foundational theories. First, a material consumption functional and self-strain energy functional is introduced from an engineering perspective, along with a variational principle involving independent dual-variable in the morphogenesis process of tensegrity structures. Next, a Symbol Parsing Method is proposed and successfully applied to the optimal morphology analysis of the icosahedral tensegrity module. Due to memory limitations in personal computers, the Singular Value Decomposition of the symbolic equilibrium matrix for the prismatic tensegrity module is constrained. As an alternative, a discrete numerical solution, the semi-symbolic parsing method, is obtained by directly utilizing a numerical equilibrium matrix. This method was recently employed to analyze and optimize a practical tensegrity footbridge designed by the authors. Lastly, the paper delves into the stability of self-equilibrium states in icosahedral and classical prismatic tensegrity modules by employing a second-order variational analysis of the self-strain energy functional. The findings presented are expected to contribute to future research on the morphogenesis of tensegrity structures.形态发生是张拉整体系统设计的一个重要方面。本文探讨了二十面体和棱柱张拉整体模的模式形成及其基础理论。首先，从工程角度介绍了材料消耗函数和自应变能函数，以及张拉整体结构形态形成过程中涉及独立双变量的变分原理。其次，提出了一种符号解析方法，并成功应用于二十面体张拉整体模块的最优形态分析。由于个人计算机的内存限制，柱形张拉整体模块的符号平衡矩阵的奇异值分解受到了限制。作为一种替代方法，直接利用数值平衡矩阵得到离散数值解，即半符号解析法。最近将该方法应用于作者设计的实际张拉整体人行桥的分析和优化。最后，通过对自应变能泛函的二阶变分分析，探讨了二十面体和经典棱柱张拉整体模的自平衡态的稳定性。所提出的研究结果有望对张拉整体结构形态发生的未来研究做出贡献。来源：复合材料力学仿真Composites FEM