【新文速递】2024年1月9日固体力学SCI期刊最新文章_ACT_System_Deform_振动_非线性_ADS_UG_理论_材料

【新文速递】2024年1月9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，Thin-Walled Structures 1 篇

International Journal of Solids and Structures

Wave propagation characteristics in a rotating soft cylinder

Yinnan Zhang, Kecheng Li, Congshan Liu, Haifei Zhan, Chaofeng Lü

doi:10.1016/j.ijsolstr.2023.112639

旋转软圆柱体中的波传播特性

Wave propagation characteristics in rotating cylindrical structures, which reflect the dynamic properties of the structures, play a crucial role in various applications. This paper systematically investigates the wave propagation characteristics in a rotating soft cylinder, based on the Neo-Hookean and Ogden soft material models. The finite deformation theory and the linear incremental theory are employed to solve the large deformation induced by rotation and the small perturbation caused by wave propagation. It is found that rotation changes the geometry size, induces the asymmetry of the forward and backward waves, and leads to the discontinuous frequency change. At large wave numbers, the effect of asymmetry can be neglected for a thin cylinder. However, for small wavenumbers, the effect of asymmetry is significant for both thin and thick cylinders. As the speed increases, the frequency will undergo a sudden and discontinuous change in both Neo-Hookean and Ogden models. In the Ogden model, the snap-through in frequency is observed, during which the dispersion curves will change dramatically. The results of this work will benefit the application of the rotating systems with soft rollers and wheels, and the frequency characteristics can be used in structural detection and signal generation.

旋转圆柱结构中的波传播特性反映了结构的动态特性，在各种应用中起着至关重要的作用。本文基于 Neo-Hookean 和 Ogden 软材料模型，系统地研究了旋转软圆柱体中的波传播特性。采用有限变形理论和线性增量理论求解旋转引起的大变形和波传播引起的小扰动。研究发现，旋转改变了几何尺寸，引起了前进波和后退波的不对称，并导致频率的不连续变化。在波数较大时，薄圆柱体的不对称影响可以忽略。然而，在小波数情况下，不对称对薄圆柱体和厚圆柱体的影响都很大。随着速度的增加，频率在新胡肯模型和奥格登模型中都会发生突然和不连续的变化。在奥格登模型中，频率会发生突变，其间频散曲线会发生剧烈变化。这项工作的结果将有利于带有软滚子和轮子的旋转系统的应用，其频率特性可用于结构检测和信号生成。

Thin-Walled Structures

Shake table test and seismic fragility analysis of transmission tower-line system considering duration effect

Li Tian, Meng Yang, Juncai Liu, Zhen Ma, Junrong Gong, Haomiao Chen, Xianchao Luo

doi:10.1016/j.tws.2024.111584

考虑持续时间效应的振动台试验和输电塔线系统地震脆性分析

Although extensive attention has been devoted to the influence of ground motion duration on the seismic performance of various structures, the integration of the duration effect into the seismic analysis of transmission tower-line systems (TTLSs) has been rarely studied, leading to a lack of understanding regarding the relationship between the ground motion duration and the seismic response of TTLSs. This paper aims to quantify the duration effect on the structural performance and seismic fragility of a TTLS through shake table tests and numerical simulations. To achieve this goal, a reduced-scale experimental model of a TTLS is carefully designed and fabricated, and a group of ground motions with contrasting durations is chosen using a spectral matching method. Subsequently, shake table tests are conducted to examine the duration effect on the seismic responses of the TTLS. The recorded data indicates that long-duration ground motions (LDGMs) significantly amplify the seismic responses and have the potential to degrade the structural performance. Furthermore, a validated finite element model of the TTLS is employed to compute its nonlinear responses from elastic behavior to complete plasticity utilizing incremental dynamic analysis. Probabilistic assessments are also conducted to investigate the seismic fragility and loss of the TTLS. The findings reveal higher damage probabilities and more severe losses caused by LDGMs, emphasizing the importance of considering the duration effect in the seismic performance assessment of TTLSs. This investigation contributes to a meaningful exploration for reliably assessing the seismic capacity of TTLSs while accounting for the duration effects.

尽管地震动持续时间对各种结构抗震性能的影响已受到广泛关注，但将持续时间效应纳入输电塔线系统（TTLS）抗震分析的研究却很少，导致人们对地震动持续时间与 TTLS 地震响应之间的关系缺乏了解。本文旨在通过振动台试验和数值模拟，量化持续时间对 TTLS 结构性能和地震脆性的影响。为实现这一目标，我们精心设计并制作了一个缩小尺度的 TTLS 实验模型，并使用频谱匹配法选择了一组持续时间对比强烈的地面运动。随后，进行了振动台试验，以检验持续时间对 TTLS 地震响应的影响。记录的数据表明，长持续时间地震动（LDGMs）会显著放大地震响应，并有可能降低结构性能。此外，还采用了经过验证的 TTLS 有限元模型，利用增量动态分析计算其从弹性行为到完全塑性的非线性响应。还进行了概率评估，以研究 TTLS 的地震脆性和损失。研究结果表明，LDGMs 造成的破坏概率更高，损失更严重，强调了在 TTLS 地震性能评估中考虑持续时间效应的重要性。这项研究有助于为可靠评估 TTLS 的抗震能力同时考虑持续时间效应进行有意义的探索。

来源：复合材料力学仿真Composites FEM

【新文速递】2023年12月28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 PlasticityBehaviour of TRIP-aided Medium Mn Steels investigated by in situ Synchrotron X-Ray Diffraction Experiments and Microstructure-Based Micromechanical ModellingMathias Lamari, Sébastien Y.P. Allain, Guillaume Geandier, Marc Ponçot, Astrid Perlade, Kangying Zhudoi:10.1016/j.ijplas.2023.103866通过原位同步辐射 X 射线衍射实验和基于微结构的微机械模型研究 TRIP 辅助中锰钢的行为Medium Mn steels belong to a new generation of advanced high-strength steels whose superior mechanical properties are explained by their ultrafine-grained ferrite/austenite/martensite microstructures and a possible transformation induced plasticity (TRIP) related to the stability of retained austenite. The mechanical behaviour of a set of model medium Mn steels is investigated during tensile testing using a combination of high-energy X-ray diffraction (HEXRD) and digital image correlation (DIC) measurements. HEXRD allows for the time-resolved determination of transformation kinetics and in situ stress partitioning among the different constituting phases. DIC provides precise spatiotemporal information on the strain evolution along the gauge length, particularly at the position of the diffracting volume. These experiments served to calibrate an innovative mean field micromechanical model which accounts for the local behaviour of each phase, as well as the strain-induced martensitic transformation (SIMT) of retained austenite. The work-hardening of both austenite and ferrite is modeled using a dislocation-based size-sensitive approach which includes kinematic hardening contributions. The behaviours of fresh and strain-induced martensite are predicted using a genuine model derived from the continuous composite approach. The model for SIMT is based on a thermodynamic assessment of the stability of retained austenite. The overall model is thus sensitive to the size of the microstructure components, their local chemistry, and their respective stability.中锰钢属于新一代先进的高强度钢，其优异的机械性能可通过其超细晶粒铁素体/奥氏体/马氏体微结构以及与残留奥氏体稳定性有关的可能的转化诱导塑性（TRIP）来解释。在拉伸测试过程中，结合使用高能 X 射线衍射 (HEXRD) 和数字图像相关 (DIC) 测量方法，对一组中锰钢模型的机械性能进行了研究。高能 X 射线衍射可对转变动力学和不同组成相之间的原位应力分配进行时间分辨测定。数字图像相关性测量则可提供沿量规长度方向应变演变的精确时空信息，特别是在衍射体积的位置。这些实验有助于校准创新的平均场微机械模型，该模型考虑了各相的局部行为以及保留奥氏体的应变诱导马氏体转变（SIMT）。奥氏体和铁素体的加工硬化采用基于位错的尺寸敏感方法建模，其中包括运动硬化贡献。新鲜马氏体和应变诱导马氏体的行为是通过连续复合方法衍生的真实模型进行预测的。SIMT 模型基于对残留奥氏体稳定性的热力学评估。因此，整体模型对微观结构成分的大小、局部化学性质及其各自的稳定性非常敏感。Thin-Walled StructuresSimultaneous optimal tri-directional distribution of material and porosity in functionally graded plates under free vibrationHuy Tang, Nam V. Nguyen, Jaehong Leedoi:10.1016/j.tws.2023.111496自由振动条件下功能分级板中材料和孔隙率的三向同步优化分布This paper for the first time attempts to find the simultaneously optimal three-dimensional distribution of porosity and material phases in functionally graded materials (FGMs) model that altogether maximize the natural frequency of porous FG plates. By using the same concept of non uniform rational B-splines (NURBS) based interpolation for the material distribution, the problem of finding the optimal porosity distribution is enabled. An upper bound of porosity is pointed out, which is necessary for considering the porosity design variables. Generalized shear deformation theory (GSDT) in the framework of isogeometric analysis (IGA) for free vibration analysis of the porous FG plates is verified with previous works. The findings are: in the optimal design of material only, the uniformly distributed pores have a neutral or detrimental effect on 4-side constrained plates but slightly increase the frequency for the cantilever plate; and with that same amount of porosity, the simultaneously optimal distributions of pores, similar to those in bio-materials or natural bones in the way that are most foam-like in the center or at the furthest from the boundaries, result in lighter yet of significantly elevated vibration frequency structures.本文首次尝试在功能分级材料（FGMs）模型中同时找到孔隙率和材料相的最佳三维分布，从而最大化多孔 FG 板的固有频率。通过使用基于非均匀有理 B-样条曲线（NURBS）插值的相同概念来处理材料分布，可以解决寻找最佳孔隙率分布的问题。指出了孔隙率的上限，这对于考虑孔隙率设计变量是必要的。在等几何分析（IGA）框架下，针对多孔 FG 板自由振动分析的广义剪切变形理论（GSDT）与之前的工作进行了验证。研究结果表明：仅在材料优化设计中，均匀分布的孔隙对四面受约束板的影响为中性或有害，但会略微增加悬臂板的频率；在孔隙率相同的情况下，同时优化孔隙分布，类似于生物材料或天然骨骼中的孔隙分布，即在中心或离边界最远的地方形成最类似泡沫的孔隙，从而形成更轻但振动频率显著升高的结构。来源：复合材料力学仿真Composites FEM