【新文速递】2024年3月26日固体力学SCI期刊最新文章

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 3 篇International Journal of Solids and StructuresEnergy variation and stress fields of spherical inclusions with eigenstrain in three-dimensional anisotropic bi-materialsT. Richetondoi:10.1016/j.ijsolstr.2024.112748 三维各向异性生物材料中具有特征应变的球形夹杂物的能量变化和应力场In this study, expressions for the interior stress fields of a spherical inclusion with uniform eigenstrain embedded in an anisotropic bi-material featuring a planar interface are derived. These expressions involve surface integrals of the imaginary term of the first derivative of the Green tensor in an anisotropic bi-material which are well-suited for standard numerical integrations. Specific formulations are provided for cases where the inclusion belongs to either the same material or both materials. Additionally, expressions are presented for the equivalent Eshelby tensor. The interior stress fields and variations in elastic strain energy are computed using cubic elastic constants of Cu. Various inclusion positions relative to the interface, eigenstrain forms, and crystallographic orientations are considered. For instances involving dilatational eigenstrain, the elastic strain energy variation with the inclusion’s position may exhibit multiple extrema. The global minimum and maximum consistently occur when the inclusion spans both materials. In the context of symmetrical tilt boundaries, energy variations are perfectly symmetric, with a global minimum on the interface that decreases with the tilt angle. The significance of the observed energy variations for defects segregation is quantitatively assessed by comparing them with the interaction energy between an eigenstrain and a grain boundary stress field.本研究推导了具有均匀特征应变的球形内含体的内部应力场表达式，该内含体嵌入具有平面界面的各向异性双材料中。这些表达式涉及各向异性双材料中格林张量一阶导数虚项的表面积分，非常适合标准数值积分。对于包含属于同一种材料或两种材料的情况，提供了具体的计算公式。此外，还给出了等效 Eshelby 张量的表达式。内部应力场和弹性应变能的变化是使用 Cu 的立方弹性常数计算得出的。考虑了相对于界面的各种夹杂位置、特征应变形式和晶体学取向。在涉及扩张特征应变的情况下，弹性应变能随包裹体 位置的变化可能会呈现多个极值。全局最小值和最大值始终出现在夹杂物横跨两种材料时。在对称倾斜边界的情况下，能量变化是完全对称的，界面上有一个随倾斜角减小的全局最小值。通过将观察到的能量变化与特征应变和晶界应力场之间的相互作用能量进行比较，对缺陷偏析的重要意义进行了定量评估。Mechanics of MaterialsA coordinate-free guide to the mechanics of thin shellsGiuseppe Tomassettidoi:10.1016/j.mechmat.2024.104961薄壳力学无坐标指南In this tutorial, we provide a coordinate-free derivation of the system of equations that govern equilibrium of a thin shell that can undergo shear. This system involves tensorial fields representing the internal force and couple per unit length that adjacent parts of the shell exchange at their common boundary. By an appropriate decomposition of those quantities, we obtain a representation of the internal power in terms of time derivatives of suitable strain measures. Subsequently, we propose constitutive equations that employ these strain measures as independent variables. After specializing the theory to the case of unshearable shells, we linearize the resulting equations. As an application, we study the free vibrations of a pressurized spherical shell, showcasing the advantages of a coordinate-free perspective, which simplifies both the deduction and the solution of the final governing equations.在本教程中，我们提供了一个无坐标推导方程组，该方程组控制着可承受剪切力的薄壳的平衡。该系统涉及代表内力和单位长度耦合的张量场，壳的相邻部分在它们的共同边界上交换内力和耦合。通过对这些量进行适当的分解，我们可以用适当应变量的时间导数来表示内力。随后，我们提出了采用这些应变量作为自变量的构成方程。在将理论专门化为不可剪切壳体的情况后，我们将所得方程线性化。作为应用，我们研究了受压球壳的自由振动，展示了无坐标视角的优势，它简化了最终控制方程的推导和求解。International Journal of PlasticityVirtual laboratory enabled constitutive modelling of dual phase steelsWencheng Liu, Xinghao Li, Ming Liu, Hao Cui, Jia Huang, Yong Pang, Jun Madoi:10.1016/j.ijplas.2024.103930虚拟实验室支持双相钢的结构建模Accurate and efficient characterization and modelling of deformation responses are critically essential in the development of advanced metal forming processes. This work presents a virtual laboratory enabled constitutive framework for modelling complex deformation responses of dual phase (DP) steels under complex stress states, based on multi-phase full-field crystal plasticity (CP) and advanced phenomenological modelling. In the CP based virtual testing method, kinematic hardening and degradation of elastic modulus are modelled in particular to improve the capability for describing evolving microstructure induced mechanical responses of DP steels. The workflow of this framework is completely built and numerically implemented, including (i) representative volume element (RVE) generation based on microstructure characterisation, (ii) identification of multiphase CP model parameters, (iii) prediction of elastic modulus degradation, (iv) prediction of yield stresses and plastic potentials in uniaxial tension and biaxial tension with various stress ratios, and (v) prediction of stress–strain curves in reverse tension compression. Using DP780 and DP980 as case materials, the corresponding physical experiments are conducted to verify the accuracy of the virtual tests, showing a good agreement between the virtual and experimental approaches. Both experimental and virtual tests are used to calibrate advanced phenomenological constitutive models that include non-linear elasticity, anisotropic yielding, and kinematic hardening. The calibrated models are implemented into the finite element (FE) codes to predict complex deformation and springback behaviours of DP780 and DP980 sheets in U-bending processes. In comparison with forming experiments of U-channel parts, the virtually calibrated models are validated and show good performance in predicting deformation and springback behaviours, providing a high capability for process analysis. The findings support that the virtual laboratory enabled modelling approach could be a substitute for extensive, expensive, and hard-to-access physically mechanical experiments required in the model calibration for a more effective and efficient analysis of metal forming processes.对变形响应进行准确有效的表征和建模对于先进金属成型工艺的开发至关重要。这项研究基于多相全场晶体塑性（CP）和先进的现象学建模，提出了一个虚拟实验室构成框架，用于模拟双相钢（DP）在复杂应力状态下的复杂变形响应。在基于晶体塑性的虚拟测试方法中，特别对运动硬化和弹性模量退化进行了建模，以提高描述双相钢微观结构诱导的机械响应演变的能力。该框架的工作流程已完全建立并在数值上实现，包括：(i) 根据微观结构特征生成代表性体积元素 (RVE)；(ii) 确定多相 CP 模型参数；(iii) 预测弹性模量退化；(iv) 预测单轴拉伸和双轴拉伸中的屈服应力和塑性势能，以及各种应力比；(v) 预测反向拉伸压缩中的应力应变曲线。以 DP780 和 DP980 为案例材料，进行了相应的物理实验来验证虚拟测试的准确性，结果表明虚拟方法与实验方法之间具有良好的一致性。实验和虚拟测试都用于校准先进的现象学构成模型，包括非线性弹性、各向异性屈服和运动硬化。校准模型被应用到有限元（FE）代码中，以预测 DP780 和 DP980 板材在 U 形弯曲过程中的复杂变形和回弹行为。与 U 型槽零件的成型实验相比，虚拟校准模型得到了验证，并在预测变形和回弹行为方面表现出良好的性能，为工艺分析提供了很高的能力。研究结果表明，虚拟实验室建模方法可以替代模型校准所需的大量昂贵且难以获得的物理机械实验，从而更有效、高效地分析金属成型工艺。Thin-Walled StructuresWorking mechanism evaluations of full-scale joints with bolted-cover plate connection for modular steel buildingsKe Cao, Si-Yuan Zhai, Yi-Fan Lyu, Guo-Qiang Li, Wei-Yong Wang, Chen Chendoi:10.1016/j.tws.2024.111772模块化钢结构建筑中采用螺栓盖板连接的全尺寸接头的工作机理评估The force-reliability of the modular structural joints is crucial for ensuring the structural integrity of modular steel buildings. However, the welds connecting the beam and column within the module are susceptible to tear during seismic events. This mode of failure greatly undermines the ability of these joints to withstand seismic forces. Four full-scale modular structural joints with bolted-cover plate connection were designed and conducted for seismic performance testing, emphasizing the significance of methods such as reinforcing diagonal braces and strengthening flanges on the protective effect of beam-column welds in the module. The simplified modular structural joint and frame finite element model were proposed based on experimental data, refined finite element modeling, and theoretical analysis. The findings suggest that the seismic behavior of the modular structural joint remains unaffected by variations in axial compression ratio within the designed range of parameters. The beam-column weld of the module in the reinforced joint exhibits almost no weld tearing, and both strengthening methods demonstrate exceptional capacity for energy dissipation. The proposed simplified modeling method facilitates the efficient determination of the modular structural joint bearing capacity and the lateral stiffness of the modular frame. The research findings presented in this paper can serve as a valuable reference point for the engineering design of modular steel structures.模块化结构接头的受力可靠性对于确保模块化钢结构建筑的结构完整性至关重要。然而，连接模块内梁和柱的焊缝在地震事件中很容易撕裂。这种失效模式极大地削弱了这些连接件抵御地震力的能力。我们设计了四个全尺寸的模块化结构连接，并进行了螺栓盖板连接的抗震性能测试，强调了加固斜撑和加固翼缘等方法对模块中梁柱焊缝保护作用的重要意义。在实验数据、精细有限元建模和理论分析的基础上，提出了简化的模块结构连接和框架有限元模型。研究结果表明，在设计参数范围内，模块结构连接的抗震性能不受轴向压缩比变化的影响。加固连接中模块的梁柱焊缝几乎没有撕裂现象，两种加固方法都表现出卓越的消能能力。所提出的简化建模方法有助于有效确定模块结构连接处的承载能力和模块框架的侧向刚度。本文的研究成果可为模块化钢结构的工程设计提供有价值的参考。Dynamic modeling and vibration control optimization of a rotating hollow beam with ESACLD treatmentYongxin Zhang, Liang Li, Dingguo Zhang, Wei-Hsin Liaodoi:10.1016/j.tws.2024.111750使用 ESACLD 处理旋转空心梁的动态建模和振动控制优化As an active and passive hybrid control technology, enhanced segmented active constrained layer damping (ESACLD) is an intelligent damping structure for suppressing adverse vibrations in flexible structures. In this study, the three-dimensional spatial dynamic model of a rotating hollow beam with improved ESACLD treatment is established based on the finite element method in a floating frame of reference. The damping effects of the ESACLD with both edge elements and incisions are considered in the dynamic model for the first time. Simulation results show the damping performance of the ESACLD is better than traditional active constrained layer damping with or without incisions (SACLD or ACLD). The Genetic Algorithm-Backpropagation (GA-BP) neural network is used to optimize the physical parameters of ESACLD, and the optimized model can effectively suppress the transverse and flapping bending vibration. It is also found that flapping and transverse bending vibrations exhibit differential dependence on nutation and precession angular velocities; higher nutation and lower precession velocities suppress flapping bending. The existing commercial finite element software has some problems, such as low efficiency and inaccuracy. The new finite element proposed in this paper uses a new form function to ensure accuracy in the simulation of rotation and vibration and has obvious advantages in dealing with rotational structures and complex boundary conditions. Research in this work can provide a design framework for vibration prediction and control of flexible beam-like structures.作为一种主被动混合控制技术，增强型分段主动约束层阻尼（ESACLD）是一种用于抑制柔性结构不良振动的智能阻尼结构。本研究基于浮动参照系下的有限元法，建立了改进 ESACLD 处理的旋转空心梁三维空间动力模型。在动态模型中首次考虑了边缘元素和切口 ESACLD 的阻尼效应。仿真结果表明，ESACLD 的阻尼性能优于有切口或无切口的传统主动约束层阻尼（SACLD 或 ACLD）。利用遗传算法-反向传播（GA-BP）神经网络对 ESACLD 的物理参数进行了优化，优化后的模型能有效抑制横向振动和拍击弯曲振动。研究还发现，拍击振动和横向弯曲振动对转角和前冲角速度的依赖性不同；较高的转角和较低的前冲角速度可抑制拍击弯曲。现有的商业有限元软件存在一些问题，如效率低、不准确等。本文提出的新有限元采用了新的形式函数，确保了旋转和振动模拟的精度，在处理旋转结构和复杂边界条件时具有明显优势。本文的研究可以为柔性梁状结构的振动预测和控制提供一个设计框架。The influence of sandwich panel cladding on horizontal structure stiffnessBřetislav Židlický, Jiří Mareš, František Walddoi:10.1016/j.tws.2024.111771夹芯板覆层对水平结构刚度的影响This paper presents a study on the influence of sandwich panel roof cladding on the horizontal stiffness of load-bearing steel structures (stressed skin action). A full-scale test was carried out on a steel monopitch portal frame structure made in two stages – without (bare steel structure) and with roof sandwich panel cladding. Data obtained from both stages of the test are presented and are used to demonstrate the significant increase in horizontal stiffness caused by the cladding system. The test data were then used to validate an FE numerical model. A roof cladding made of composite panels is relatively stiff in its own plane. However, the critical detail is the connection of the panels to the sub-structure (e.g. purlins or rafters), i.e. the screw bearing capacity. Even within the serviceability limits, the internal sheet of the composite panel suffers a certain level of permanent bearing damage. Based on the test data, the results of the FE numerical model and the analytical approach for calculating the shear stiffness of the sandwich panels, the approach for taking into account the influence of the cladding on the horizontal stiffness was derived and compared. This approach is believed to be safe and simple for practical use, and it leads to load-bearing structure members with more slender cross-sections. In addition, the data and results that are obtained expand the limited amount of available data related to stressed skin action.本文研究了夹芯板屋顶包层对承重钢结构水平刚度的影响（受力蒙皮作用）。对一个钢制单坡门式框架结构进行了全尺寸测试，测试分两个阶段进行--无夹芯板屋顶包层（裸钢结构）和有夹芯板屋顶包层。报告中提供了两个阶段的测试数据，用于证明覆层系统显著增加了水平刚度。测试数据随后用于验证有限元数值模型。由复合板制成的屋顶覆层在其自身平面上具有相对较高的刚度。然而，关键的细节在于面板与下层结构（如檩条或椽子）的连接，即螺钉的承载能力。即使在可使用范围内，复合板的内部板材也会遭受一定程度的永久性承载损坏。根据测试数据、有限元数值模型结果和计算夹芯板剪切刚度的分析方法，得出并比较了考虑覆层对水平刚度影响的方法。这种方法在实际应用中被认为是安全和简单的，而且能使承重结构件的横截面更加细长。此外，所获得的数据和结果扩展了与受力表皮作用相关的有限可用数据量。来源：复合材料力学仿真Composites FEM