【新文速递】2024年1月28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 2 篇，International Journal of Plasticity 2 篇，Thin-Walled Structures 10 篇

International Journal of Solids and Structures

Adhesive contact mechanics of viscoelastic materials

C. Mandriota, N. Menga, G. Carbone

doi:10.1016/j.ijsolstr.2024.112685

粘弹性材料的粘接接触力学

In this study, we propose a theory of rough adhesive contact of viscoelastic materials in steady-state sliding. By exploiting a boundary formulation based on Green’s function approach, the unknown contact domain is calculated by enforcing the local energy balance at the contact edge, thus considering also the non-conservative work of internal stresses which is directly related to the odd part of the Green’s function. Theoretical predictions indicate that viscoelasticity may enhance the adhesive performance depending on the sliding velocity, thus leading to larger contact area and pull-off force compared to the equivalent adhesive elastic case The interplay between viscoelasticity and adhesion also affects the overall friction. Indeed, at low velocity, friction is strongly enhanced compared to the adhesiveless viscoelastic case, mainly due to the small-scale viscoelastic hysteresis induced by the adhesive neck close to the contact edge At higher velocity, the effect of viscoelastic hysteresis occurring at larger scales (bulk material) leads to even higher friction. Under these conditions, in the presence of adhesion, the small-scale and large-scale viscoelastic contributions to friction cannot be separated. Finally, in contrast with usual predictions for crack propagation/healing in infinite systems, we found a non-monotonic trend of the energy release rates at the trailing and leading contact edges, which is consistent with the finiteness of the contact length. All the presented results are strongly supported by existing experimental evidences.

在本研究中，我们提出了粘弹性材料在稳态滑动时的粗糙粘接接触理论。通过利用基于格林函数方法的边界公式，通过在接触边缘执行局部能量平衡来计算未知接触域，从而考虑与格林函数奇部直接相关的内应力的非保守功。理论预测表明，粘弹性可以根据滑动速度提高粘接性能，从而导致比等效粘接弹性情况下更大的接触面积和拉拔力，粘弹性和粘接之间的相互作用也影响整体摩擦。事实上，在低速时，摩擦力比无黏着的粘弹性情况明显增强，这主要是由于黏着颈部靠近接触边缘引起的小尺度粘弹性滞后。在高速时，发生在更大尺度(大块材料)上的粘弹性滞后效应导致了更高的摩擦力。在这些条件下，在存在粘附的情况下，对摩擦的小尺度粘弹性和大尺度粘弹性的贡献是不能分开的。最后，与通常对无限系统中裂纹扩展/愈合的预测相反，我们发现在接触后缘和前缘的能量释放率呈非单调趋势，这与接触长度的有限性一致。所有的结果都得到了实验证据的有力支持。

Journal of the Mechanics and Physics of Solids

Shape-Dependent Friction Scaling Laws in Twisted Layered Material Interfaces

Weidong Yan, Xiang Gao, Wengen Ouyang, Ze Liu, Oded Hod, Michael Urbakh

doi:10.1016/j.jmps.2024.105555

扭曲层状材料界面中形状相关的摩擦缩放规律

Static friction induced by moiré superstructure in twisted incommensurate finite layered material interfaces reveals unique double periodicity and lack of scaling with contact size. The underlying mechanism involves compensation of incomplete moiré tiles at the rim of rigid polygonal graphene flakes sliding atop fixed graphene or h-BN substrates. The scaling of friction (or lack thereof) with contact size is found to strongly depend on the shape of the slider and the relative orientation between its edges and the emerging superstructure, partially rationalizing scattered experimental data. A phenomenological analytical model is developed, which agrees well with detailed atomistic calculations. By carefully considering the flake edge orientation, twist angle, and sliding direction along the substrate, one should therefore be able to achieve large-scale superlubricity via shape tailoring.

在扭曲不相称的有限层状材料界面中，由波纹上层结构引起的静摩擦表现出独特的双周期性，且不随接触尺寸缩放。潜在的机制涉及在固定石墨烯或氢氮化硼衬底上滑动的刚性多边形石墨烯薄片边缘的不完整波纹砖的补偿。摩擦(或缺乏摩擦)与接触尺寸的比例很大程度上取决于滑块的形状及其边缘与新出现的上部结构之间的相对方向，这部分地合理化了分散的实验数据。建立了一个与详细的原子计算相吻合的现象学分析模型。通过仔细考虑薄片边缘方向、扭转角度和沿基材滑动方向，应该能够通过形状剪裁实现大规模的超润滑。

Revealing the shear fatigue damage mechanism of soft adhesive: Coexistence of viscoelastic and damage dissipation

Yan Xia, Han Jiang, Chengbin Yao, Zhuoran Yang, Zhongmeng Zhu, Guozheng Kang

doi:10.1016/j.jmps.2024.105556

揭示软胶粘剂剪切疲劳损伤机理:粘弹性与损伤耗散共存

Shear fatigue has become one of the typical failure modes of soft adhesives used in advanced engineering applications. The fatigue damage is naturally coexistent with the viscoelastic dissipation during the shear fatigue for typical soft adhesives, which raises difficulty in directly evaluating the actual fatigue damage evolution. In this paper, an experimental approach is proposed based on the energy balance analysis, to effectively separate the viscoelastic dissipation and damage dissipation during the shear fatigue. Accordingly, the actual shear fatigue damage mechanism of the soft adhesive under various loading periods and stress levels is comprehensively analyzed. The viscoelastic/damage dominant failure mechanisms are revealed respectively, that the viscoelastic dissipation process dominates the shear fatigue life under the short loading period or low stress level, while the damage dissipation process dominates under the opposite conditions. While the total viscoelastic dissipation is strongly dependent on the loading conditions, the total damage dissipation is found to be constant under all conditions. An energy-based fatigue life prediction model is also established based on the discovered energy dissipation mechanism to estimate the shear fatigue life of the soft adhesive under wide loading conditions. These findings provide an excellent insight into the understanding of the physical mechanism of the shear fatigue failure of soft adhesives, which is essential to assess their service lifetime and also supply an important guideline for the development of anti-fatigue soft adhesives.

剪切疲劳已成为先进工程中常用的软胶粘剂的典型失效形式之一。典型软胶粘剂在剪切疲劳过程中疲劳损伤与粘弹性耗散自然并存，这给直接评价实际疲劳损伤演变带来了困难。本文提出了一种基于能量平衡分析的试验方法，以有效地分离剪切疲劳过程中的粘弹性耗散和损伤耗散。据此，综合分析了不同加载周期和应力水平下软胶的实际剪切疲劳损伤机理。揭示了粘弹性/损伤主导破坏机制，即短加载周期或低应力水平下，粘弹性耗散过程主导剪切疲劳寿命，而损伤耗散过程主导剪切疲劳寿命。总粘弹性耗散与加载条件密切相关，但在所有条件下，总损伤耗散都是恒定的。基于所发现的能量耗散机理，建立了基于能量的疲劳寿命预测模型，用于估算软胶在大载荷条件下的剪切疲劳寿命。这些研究结果为了解软胶粘剂剪切疲劳破坏的物理机制提供了很好的见解，这对评估软胶粘剂的使用寿命至关重要，也为开发抗疲劳软胶粘剂提供了重要的指导。

International Journal of Plasticity

Atomic irradiation defects induced hardening model in irradiated tungsten based on molecular dynamics and CPFEM

Pan-dong Lin, Jun-feng Nie, Yu-peng Lu, Chang-xin Shi, Shu-gang Cui, Wen-dong Cui, Lei He

doi:10.1016/j.ijplas.2024.103895

基于分子动力学和CPFEM的辐照钨原子辐照缺陷诱导硬化模型

Tungsten plays a significant role in the nuclear industry, in which defects are generated upon exposure to irradiation. Irradiation-induced defects, such as dislocation loops and helium bubbles, are key factors in performance degradation, leading to irradiation hardening and embrittlement. The inner interaction between the dislocations and irradiation-induced defects directly determines the safety of the irradiated tungsten. However, the interaction mechanisms and evolutionary formulas remain unclear. In this study, based on systematic molecular dynamics (MD) simulations, an interaction mechanism phase map between the dislocation and dislocation loop was built as a function of the dislocation loop size and temperature. An atomically-informed mechanism-based evolution formula for dislocations and dislocation loops due to their interaction was established. Subsequently, a crystal-plasticity finite-element model (CPFEM) that contains the evolution formula obtained by MD is proposed. Based on CPFEM, the nano-indentation, uniaxial tension, and compression processes were simulated. Good agreement was achieved between the simulated and experimental results, further demonstrating the reasonability of the proposed model.

钨在核工业中起着重要的作用，在核工业中，暴露在辐照下会产生缺陷。辐照诱导缺陷，如位错环和氦气泡，是导致辐照硬化和脆化的关键因素。位错与辐照缺陷之间的内部相互作用直接决定了辐照钨的安全性。然而，相互作用机制和进化公式仍不清楚。在系统分子动力学(MD)模拟的基础上，建立了位错与位错环之间的相互作用机制相图，该相图是位错环尺寸和温度的函数。建立了位错与位错环相互作用的基于原子信息机制的演化公式。在此基础上，建立了包含MD演化公式的晶体塑性有限元模型(CPFEM)。基于CPFEM，模拟了纳米压痕、单轴拉伸和压缩过程。仿真结果与实验结果吻合较好，进一步证明了所提模型的合理性。

The influence of precipitation on plastic deformation in a high Mg-containing AlMgZn-based crossover alloy: Slip localization and strain hardening

Xiuzhen Zhang, Chao Yang, Lei Meng, Zhenghao Chen, Wu Gong, Binhan Sun, Shiteng Zhao, Deliang Zhang, Yue Li, Dengshan Zhou

doi:10.1016/j.ijplas.2024.103896

析出对高mg almgzn基交叉合金塑性变形的影响:滑移局部化和应变硬化

The distribution and partitioning of solute atoms in age-hardenable aluminum (Al) alloys markedly impact strength, ductility and failure of alloy materials, thus rendering the understanding of dislocation-obstacle (solute-rich features) interactions crucial in the development of a new class of heat-treatable Al alloys. Here, we investigate the slip mechanisms, strain localization and strain hardening of a high Mg-content (≥ 6 wt.%) lightweight AlMgZn-based crossover alloy aged to different conditions with the focus on the dislocation-obstacle interactions. It is found that due to different elemental partitioning between matrix and solute-rich features the interaction of dislocations with obstacles can be drastically different for samples with varying precipitates. The dislocations in the under-aged and near peak-aged samples show predominantly planar slip, which produces strain localization. Whereas in the over-aged sample, gliding dislocations initially bend between adjacent precipitates lying in the slip planes, and subsequently surmount them by local cross slip processes, giving rise to homogeneous slip. Through analyzing the intrinsically different strain hardening ability and characterizing deformation-induced specific dislocation configurations in the solution-treated and aged samples, it is discovered that strain localization in the form of coarse slip bands induces strain hardening in the under-aged material. To understand the enhanced strain hardening observed in the under-aged sample, four key influencing factors are proposed. In addition, the predicted yield strengths for the solution-treated and artificially aged materials match well with those experimentally measured values. The experimental results demonstrated in the current study not only apply for the microstructure design of high-performance age-hardenable Al-based alloys, they also provide new insights into understanding of general precipitation-hardened metallic alloys.

时效硬化铝(Al)合金中溶质原子的分布和分配显著影响合金材料的强度、延展性和失效，从而使得对位错-障碍(富溶质特征)相互作用的理解对开发一类新型热处理铝合金至关重要。本文研究了高mg含量(≥6wt .%)轻量化almgzn基交叉合金在不同时效条件下的滑移机制、应变局部化和应变硬化，重点研究了位错-障碍相互作用。研究发现，由于基质和富溶质特征之间的元素分配不同，对于不同析出相的样品，位错与障碍的相互作用可能会有很大的不同。欠时效和近峰时效试样的位错主要表现为平面滑移，产生应变局部化。而在过时效试样中，滑移位错最初在滑移面的相邻沉淀之间弯曲，随后通过局部交叉滑移过程超越它们，产生均匀滑移。通过分析固溶处理和时效试样应变硬化能力的本质差异，并对变形诱发的特定位错构型进行表征，发现应变局部化以粗滑移带的形式诱发了欠时效材料的应变硬化。为了理解在未龄期试样中观察到的应变硬化增强，提出了四个关键的影响因素。此外，固溶处理和人工时效材料的屈服强度预测值与实验测量值吻合较好。本研究的实验结果不仅适用于高性能时效硬化al基合金的组织设计，也为认识一般的析出硬化金属合金提供了新的见解。

Thin-Walled Structures

Minor-axis flexural buckling of Q1100 ultra high strength steel welded I-section columns

Fei Yin, Lu Yang

doi:10.1016/j.tws.2024.111644

Q1100超高强度钢焊接工字钢柱的小轴弯曲屈曲

This paper presents an experimental and numerical investigation into the minor-axis flexural buckling behavior of Q1100 ultra high strength steel (UHSS) welded I-section columns. A total of 8 column specimens, spanning two different sections, were tested. Finite element (FE) models were developed to replicate the experimental observations, and these models were subsequently employed in a parametric investigation that encompassed a wider range of specimen geometries. Concurrently, a comprehensive evaluation of the buckling curves outlined in European, North American, Australian, and Chinese codes was performed through rigorous reliability analyses. Furthermore, this study conducted a comparative analysis between the effective width method (EWM) and the modified direct strength method (DSM) for slender cross-sections. Based on the outcomes of the reliability analyses, revised buckling curves are proposed, which are specifically aimed at enhancing the design provisions for addressing minor-axis flexural buckling in Q1100 ultra high strength steel welded I-section columns.

本文对Q1100超高强度钢焊接工字截面柱的小轴屈曲行为进行了试验和数值研究。共测试了8个柱样，跨越两个不同的截面。开发了有限元(FE)模型来复 制实验观察结果，这些模型随后被用于包含更广泛的试样几何形状的参数化研究。同时，通过严格的可靠性分析，对欧洲、北美、澳大利亚和中国规范中概述的屈曲曲线进行了综合评估。此外，本文还对细长截面的有效宽度法(EWM)和改进的直接强度法(DSM)进行了对比分析。根据可靠性分析的结果，提出了修正的屈曲曲线，旨在加强Q1100超高强度钢焊接工字截面柱小轴屈曲的设计规定。

Design of lattice cylindrical shell meta-structures for broadband vibration reduction and high load-bearing capacity

Xiyue An, Xinfeng Yuan, Guoqing Sun, Xuanxuan Hou, Hualin Fan

doi:10.1016/j.tws.2024.111647

面向宽带减振和高承载能力的点阵圆柱壳元结构设计

In this paper, a new type of lattice cylindrical shell meta-structure (LCSM) with broadband vibration reduction and high load-bearing ability is designed. In particular, the proposed curved shell meta-structure is constructed by combining lattice structure and mechanical metamaterial with elastic bandgap properties. The dispersion curves of shell structure are obtained by combining Bloch's theorem with the coordinate transformation method. The vibration transmission properties and load-bearing performance of the LCSM and the sandwich LCSM are studied numerically and experimentally. The results reveal that the proposed meta-structure has excellent vibration isolation performance at broadband frequencies, and the change of structural parameters can be used to regulate the frequency range of bandgap. Especially, the existence of curvature makes the bandgap of the shell structure inevitably change when the circumferential size of the shell is changed. Moreover, the meta-structure can maintain certain broadband vibration reduction properties when increasing the load-bearing capacity. This work offers an innovative method to develop multi-functional lattice shell structures with both load-bearing and broadband vibration isolation properties.

本文设计了一种具有宽频减振和高承载能力的新型点阵圆柱壳元结构(LCSM)。特别地，本文提出的曲面壳元结构是由晶格结构和具有弹性带隙特性的力学超材料相结合而形成的。将布洛赫定理与坐标变换方法相结合，得到了壳体结构的色散曲线。通过数值和实验研究了两种结构的振动传递特性和承载性能。结果表明，所提出的元结构在宽带频段具有良好的隔振性能，结构参数的变化可用于调节带隙的频率范围。特别是曲率的存在使得壳结构的带隙不可避免地随着壳的周向尺寸的改变而改变。此外，元结构在提高承载能力的同时还能保持一定的宽频带减振性能。这项工作为开发具有承载和宽带隔振性能的多功能格壳结构提供了一种创新方法。

Strut and stochastic polymer reinforcement interpenetrating phase composites: Static, strain-rate and dynamic damping performance

Agyapal Singh, Nikolaos Karathanasopoulos

doi:10.1016/j.tws.2024.111618

支撑和随机聚合物增强互穿相复合材料:静态、应变率和动态阻尼性能

The current work investigates the static, strain-rate and dynamic damping performance of interpenetrating phase composites (IPCs) engineered with polymer-based, isotropic, strut and stochastic reinforcement phase metamaterial topologies. In particular, BCC, random function and spinodal-based, polymer-rubbery phase IPC designs are investigated. Their specific energy absorption (SEA) and crush force efficiency (CFE) are assessed over different loading rates and compared to the ones reported for a wide range of existing architected advanced materials. It is shown that spinodal-based IPC designs outperform most comparable density advanced materials at increased loading rates, yielding SEA values that approach 16 J/g, combined with 90% CFE values. The mechanism allowing for the high strain-rate sensitive and ductile performance is first explicated. Moreover, machine learning modeling is employed to assess the significance of the underlying influential design parameters of the investigated polymer-based IPCs. The results indicate that the reinforcement phase type is nearly two times more important than the reinforcement phase content at higher strain rates, with a nearly loading-rate insensitive effect on the constitutive response. The dynamic damping performance of the architected composites is superior than the one obtained for the underlying reinforcement phase, while it depends on the reinforcement phase. For all designs, the loss modulus increases over a broad range of frequencies, contrary to the negative damping-frequency dependence recorded for the underlying reinforcement phase. The results are expected to serve as a reference in the analysis and design of polymer-based, multiphase interpenetrating phase composites, with reinforcement topologies and viscoelastic attributes beyond the ones considered here.

目前的工作是研究具有聚合物基、各向同性、支撑和随机增强相超材料拓扑结构的互穿相复合材料(IPCs)的静态、应变率和动态阻尼性能。特别研究了BCC、随机函数和基于spinodal的聚合物橡胶相IPC设计。它们的比能吸收(SEA)和碾压力效率(CFE)在不同的加载率下进行了评估，并与现有各种先进建筑材料的报告进行了比较。结果表明，在增加加载速率时，基于spinodal的IPC设计优于大多数类似密度的先进材料，SEA值接近16 J/g, CFE值为90%。首先阐明了高应变率敏感性和延性的机理。此外，采用机器学习建模来评估所研究的聚合物基IPCs的潜在影响设计参数的重要性。结果表明，在高应变速率下，增强相类型的重要性是增强相含量的近两倍，且对本构响应几乎不敏感。结构复合材料的动态阻尼性能优于底层增强相，但与增强相有关。对于所有设计，损耗模量在很宽的频率范围内增加，这与底层增强阶段记录的负阻尼频率依赖相反。研究结果有望为基于聚合物的多相互穿相复合材料的分析和设计提供参考，这些材料的增强拓扑结构和粘弹性属性超出了本文所考虑的范围。

Shear behavior of perforated steel plate shear connectors in innovative modular steel channel–concrete composite floor systems

Jiaopeng Fang, Lingyu Zhou, Jinkai Fan, Chaohu Dai, Fengui Li, Fei Liao

doi:10.1016/j.tws.2024.111626

创新模块化钢槽-混凝土组合楼板系统中穿孔钢板剪切接头的剪切性能

This study aims to investigate the shear behavior of perforated steel plate (PSP) shear connectors used in a novel modular steel channel–concrete composite floor (MSCCF) system, designed to eliminate in-situ wet construction and expedite assembly. Within this context, to understand the efficiency of these PSP connectors, fifteen PSP connectors were experimental evaluated through push-out tests, investigating variables such as PSP thickness, opening diameter, load-bearing area of PSPs, strength of PSPs, concrete strength, and the number of PSPs. Finite element analysis was also performed via ABAQUS to further reveal the working mechanism of PSP connectors. The test results showed that thin PSP connectors failed mainly due to flexural-shear failure or fracture, whereas thicker PSP connectors failed from concrete crushing. Despite the connectors exhibited high shear strength, their characteristic slip varied between 2.32 to 5.35 mm, not meeting the 6 mm ductility requirement for shear connectors in Eurocode 4. An upward trend in shear capacity was observed with increasing PSP thickness, yet a compromise in ductility. Furthermore, opening diameters influenced both shear stiffness and ductility. The spacing between PSPs also played a pivotal role in determining shear capacity. A small spacing induced overlapping concrete stress fields between each PSP layer, resulting in a reduction in shear capacity. An equation to predict the shear capacity of PSP connectors, accounting for PSP-concrete interaction, was developed. The shear capacity values calculated from the equation aligned well with the test results, highlighting the potential and design considerations of PSP connectors in MSCCF systems.

本研究旨在研究新型模块化钢槽混凝土复合楼板(MSCCF)系统中使用的穿孔钢板(PSP)剪切接头的剪切性能，该系统旨在消除原位湿施工并加快组装。在这种情况下，为了了解这些PSP连接器的效率，通过推出测试对15个PSP连接器进行了实验评估，研究了PSP厚度、开口直径、PSP承载面积、PSP强度、混凝土强度和PSP数量等变量。通过ABAQUS进行有限元分析，进一步揭示PSP连接器的工作机理。试验结果表明，薄型PSP接头的破坏主要是由于弯剪破坏或断裂，而较厚的PSP接头的破坏主要是由于混凝土破碎。尽管连接器具有较高的抗剪强度，但其特征滑移在2.32至5.35 mm之间变化，不符合欧洲规范4中抗剪连接器6 mm的延性要求。随着PSP厚度的增加，剪切能力呈上升趋势，但延性有所降低。此外，开口直径对剪切刚度和延性都有影响。PSPs之间的间距也在决定抗剪能力方面起着关键作用。较小的间距导致各PSP层之间混凝土应力场重叠，导致抗剪能力降低。建立了考虑PSP-混凝土相互作用的PSP接头抗剪承载力预测方程。根据公式计算的剪切能力值与测试结果吻合良好，突出了PSP连接器在MSCCF系统中的潜力和设计考虑。

Modeling of flexible bevel gear rotor systems: modal and dynamic characterization

Zhaoyang Tian, Jinyuan Tang, Zehua Hu, Haonan Li, Xiannian Kong, Wenzhe Zhang, Feiteng Chen, Hongtao Dong

doi:10.1016/j.tws.2024.111627

柔性锥齿轮转子系统建模:模态和动态特性

Bevel gears, a crucial part of aircraft transmission systems, are more susceptible to wheel body vibration issues as lightweight requirements rise. In the past, the gear wheel body was often considered rigid while assessing the dynamic properties of gear systems. Constructing a bevel gear model with a thin-walled structure might not be appropriate for this modeling technique; this research suggests a dynamic model that considers the flexibility of bevel gears. The web and teeth structure of the gear are preserved by realistic modeling using three-dimensional hexahedral components. The component mode synthesis (CMS) approach reduces the model order for increased computational efficiency. To confirm the accuracy of the modeling method, the modal frequencies and vibration shapes of the proposed model single-gear shaft are compared with results from experiments and ABAQUS. By contrasting ABAQUS system-level meshing modal frequencies and vibration shapes, the accuracy of the system model assembly is further confirmed. The model examines the impact of bevel gear flexibility on the modal frequencies, modal vibration shapes, and system dynamic properties. The mode shape diagram at dangerous modal frequencies found using the modal strain energy technique and the vibration displacement cloud maps at resonance speeds computed using the Newmark-β method are mutually verified, and this demonstrates that lightweight bevel gears are more susceptible to excitation due to nodal diameter type vibrations. Proposed and traditional models anticipate substantially different resonance speeds since the traditional model assumes that the gear, being a rigid disk, can only excite the shaft's bending mode of vibration. The proposed model provides a more comprehensive description of the dynamic characteristics of bevel gear systems, providing a theoretical basis and optimization tool for the high-performance design, vibration reduction, and noise control of high-speed lightweight gear transmission systems.

锥齿轮是飞机传动系统的关键部件，随着轻量化要求的提高，锥齿轮更容易受到轮体振动问题的影响。过去，在评估齿轮系统的动力特性时，通常认为齿轮体是刚性的。建立一个薄壁结构的锥齿轮模型可能不适合这种建模技术;本研究提出了一种考虑锥齿轮柔性的动态模型。齿轮的腹板和齿结构是通过使用三维六面体部件的逼真建模来保存的。构件模态综合(CMS)方法降低了模型阶数，提高了计算效率。为了验证建模方法的准确性，将模型单齿轮轴的模态频率和振型与实验结果和ABAQUS结果进行了比较。通过对比ABAQUS系统级啮合模态频率和振型，进一步验证了系统模型装配的精度。该模型考察了锥齿轮柔性对模态频率、模态振型和系统动态特性的影响。利用模态应变能技术得到的危险模态频率下的振型图与利用Newmark-β方法计算的共振速度下的振动位移云图相互验证，表明轻量化锥齿轮更容易受到节径型振动的激励。由于传统模型假设齿轮作为一个刚性圆盘，只能激发轴的弯曲振动模式，因此所提出的模型和传统模型预测的共振速度有很大不同。该模型更全面地描述了锥齿轮传动系统的动态特性，为高速轻量化齿轮传动系统的高性能设计、减振和噪声控制提供了理论依据和优化工具。

Space-efficient protection for cylindrical batteries embedded into multi-cell structures: evaluation and mechanistic investigation

Shengru Chen, Mingzhe Zhou, Xin Zhao, Ziwen Zhang, Lingling Hu

doi:10.1016/j.tws.2024.111630

嵌入多电池结构的圆柱电池的空间高效保护:评估和机理研究

Mechanical protection of battery packs is challenging due to the limited available space. While filling packing gaps with protective structures is practical and space-efficient, there is a lack of reference for selecting proper matrix materials for the structures. To address this issue, we conducted compression tests on cylindrical battery packs embedded into 3D-printed thin-walled resin, foam, and polyurethane structures. A comprehensive comparison was made among battery packs protected by various materials, as well as the non-protected one, to evaluate their protecting performance including deformation nonuniformity, failure rate, and failure thresholds under various loading conditions. Results showed that the resin- and foam-protected battery packs experienced less damage under similar load level and similar crushing energy, respectively. The underlying mechanisms were further investigated by combining tests and simulations. It is revealed that the stiffness of filling material greatly influences the protective effect, which results in the different distributions of both stress and strain energy in the battery pack. The stiffness balance between the foam and the batteries to achieve better protecting effect was also unlocked under varying crushing energies. Our findings shed light on the space-efficient protection of battery packs under crash.

由于可用空间有限，电池组的机械保护具有挑战性。虽然用保护结构填充填料间隙是实用和节省空间的，但在选择合适的结构基质材料方面缺乏参考。为了解决这个问题，我们对嵌入3d打印薄壁树脂、泡沫和聚氨酯结构的圆柱形电池组进行了压缩测试。对不同材料保护的电池组和未保护的电池组进行综合比较，评估其在不同载荷条件下的保护性能，包括变形不均匀性、故障率和失效阈值。结果表明，在相同的载荷水平和相同的破碎能量下，树脂保护和泡沫保护的电池组损伤较小。通过实验和模拟相结合的方法进一步研究了其潜在机制。研究表明，填充材料的刚度对保护效果有很大影响，导致电池组内应力和应变能的分布不同。在不同的破碎能量下，泡沫与电池之间的刚度平衡也被打破，以达到更好的保护效果。我们的研究结果揭示了在碰撞情况下保护电池组的空间效率。

Experimental and numerical investigation on the column-beam connection in the corrugated steel plate-concrete composite frame

Zexuan Sun, Yun Zou, Jianxin Shi, Jiawei Miao, Ming Chen, Lei Xu

doi:10.1016/j.tws.2024.111631

波纹钢板-混凝土组合框架柱-梁连接的试验与数值研究

The steel tubular-corrugated steel plate confined concrete composite column (S-CSC column) and the reinforced concrete beam with U-shaped corrugated steel webs (U-SCC beam) have recently been developed as efficient steel-concrete composite construction. The connection method of the S-CSC column and U-SCC beam with convenient construction and clear force transmission was proposed based on the design principle of "strong connection and weak member". A cyclic loading test was conducted on the S-CSC column and U-SCC beam connection to analyze failure modes, load-displacement curves, strains in the core region of the connection, energy dissipation capacity, and stiffness degradation. Experimental results revealed that the connection's ultimate failure occurred at the beam, where the plastic hinge zone underwent outward relocation, while the core region of the connection remained undamaged. The load-displacement curves exhibited full, indicating a good energy dissipation capacity and strains in the core region of the connection were uniformly distributed across various positions. To elucidate the force transmission path and force mechanism of each component within the core region of the connection, a finite element model was established. Additionally, parametric analyses were conducted to examine the impact of different parameters on the connection's bearing capacity. Lastly, based on a shear model that considers the concrete and steel in the core region of the connection, a calculation method for shear capacity was proposed.

钢管-波纹钢板约束混凝土组合柱(S-CSC柱)和u形波纹钢腹板钢筋混凝土梁(U-SCC梁)是近年来发展起来的高效钢-混凝土组合结构。根据“强连接、弱构件”的设计原则，提出了施工方便、传力清晰的S-CSC柱与U-SCC梁的连接方法。对S-CSC柱- U-SCC梁节点进行循环加载试验，分析节点破坏模式、荷载-位移曲线、节点核心区域应变、耗能能力和刚度退化情况。试验结果表明，连接的最终破坏发生在梁上，塑性铰区向外移位，而连接的核心区域完好无损。荷载-位移曲线饱满，表明节点具有良好的能量耗散能力，节点核心区域的应变分布均匀。为了阐明连接核心区域内各构件的传力路径和受力机理，建立了有限元模型。此外，还进行了参数分析，考察了不同参数对连接承载力的影响。最后，在考虑节点核心区混凝土和钢筋的剪力模型基础上，提出了节点抗剪承载力的计算方法。

Effect of damping on torsional-flexural frequencies of monosymmetric thin-walled beams scanned by moving vehicles

Y.B. Yang, X.Q. Mo, K. Shi, S.Y. Gao, N. Liu, Z.Z. Han

doi:10.1016/j.tws.2024.111633

阻尼对运动车辆扫描单对称薄壁梁扭转弯曲频率的影响

This paper investigates the effect of damping on the torsional-flexural frequencies of monosymmetric thin-walled beams via the scanning by a single-axle test vehicle. A bi-directional damping model is adopted to account for the vertical and torsional-flexural motions of the beam, as they are mechanically uncoupled. To start, the closed-form solutions are derived for the vehicle, the beam and the vehicle-bridge contact responses. Based on the hypothesis of rigid cross sections, the rocking contact response is derived, which enables the torsional-flexural frequencies of the beam to be separated from the vertical ones. Both uniform and bi-directional damping properties are considered for the beam. The pollution effect of pavement roughness is overcome by using the residual contact response generated by two connected single-axle test vehicles. Through the parametric analysis, it is confirmed that: (1) the rocking contact response enables the first few torsional-flexural frequencies to be separately retrieved; (2) the damping ratio in each direction only affects the detectability of the frequencies, especially those of the high modes, in that direction for monosymmetric cross sections; (3) the residual contact response exhibits some robustness in identifying the frequencies of thin-walled beams with surface roughness and environmental noise effect; (4) a test vehicle moving in the side lane (with larger eccentricity from bridge's centerline) at a speed of 10 m/s (36 km/h) is recommended for the field test.

通过单轴试验车的扫描，研究了阻尼对单对称薄壁梁扭弯频率的影响。采用双向阻尼模型来考虑梁的垂直和扭转弯曲运动，因为它们是机械不耦合的。首先，推导了车辆、梁和车桥接触响应的封闭解。基于刚性截面假设，推导了梁的振动接触响应，使梁的扭转弯曲频率与垂直频率分离。同时考虑了梁的均匀和双向阻尼特性。利用两辆连接的单轴试验车辆产生的剩余接触响应克服了路面粗糙度的污染效应。通过参数分析，证实了:(1)振动接触响应使前几个扭弯频率能够分别得到;(2)对于单对称截面，各方向的阻尼比只影响该方向频率的可探测性，特别是高模态的频率可探测性;(3)残余接触响应对具有表面粗糙度和环境噪声影响的薄壁梁的频率识别具有一定的鲁棒性;(4)现场试验建议采用车速为10 m/s (36 km/h)的试验车辆行驶在侧车道(距桥梁中心线偏心率较大)。

Hydroelastic analysis of an elastic thin-walled structure obliquely impacting a calm water surface

Hang Xie, Huanhuan Peng, Fang Liu, Xinyu Liu, Huilong Ren

doi:10.1016/j.tws.2024.111638

斜冲击平静水面弹性薄壁结构的水弹性分析

To elucidate the oblique impact mechanism of thin-walled structures, a drop experiment is carried out on an elastic structure with a drop height ranging from 250 mm to 900 mm and an inclination angle ranging from 0° to 20°. The basic hydrodynamic characteristics, including the impact load and stress response, are clarified through combination with modal analysis. Although the leeward side has a small hydrodynamic load, the stress level on this side is close to that on the windward side. The importance of oscillation sources (including the vibration of the experimental system, the hydroelastic effect and the fluid oscillation) was identified by the wavelet transform, which shows the advantages in clarifying the multiple vibrations induced by the close frequency. The influence of the inclination angle on pressure and stress is further discussed, revealing that the inclination angle greatly increases the impact pressure, but the influence on the stress response is irregular. The nondimensional coefficients at different drop heights still exhibit obvious irregularities, which are related to fluid oscillations. These findings further confirm the complexity of the structural response to asymmetric slamming.

为了阐明薄壁结构的斜冲击机理，对弹性结构进行了跌落实验，跌落高度为250 ~ 900 mm，倾斜角为0°~ 20°。结合模态分析，阐明了冲击载荷和应力响应等基本水动力特性。虽然背风侧的水动力载荷较小，但背风侧的应力水平与迎风侧的应力水平接近。利用小波变换识别了实验系统的振动、水弹性效应和流体振动等重要振动源，表明了小波变换在解释由相近频率引起的多重振动方面的优势。进一步讨论了倾角对压力和应力的影响，发现倾角大大增加了冲击压力，但对应力响应的影响是不规则的。不同落差高度下的无量纲系数仍表现出明显的不规则性，这与流体振荡有关。这些发现进一步证实了结构对不对称撞击反应的复杂性。

Analysis of dispersion characteristics and control of multiple passbands in a metamaterial pipe

Mohd Iqbal, Anil Kumar, Mahesh Murugan Jaya

doi:10.1016/j.tws.2024.111643

超材料管道中多通带色散特性分析及控制

Understanding and controlling pipe vibrations are of key concern as they affect the serviceability and performance of pipeline systems. A novel metamaterial concept can be exploited to control these vibrations. In this article, propagation characteristics of flexural waves in a pipe coupled with rack are investigated. The dispersion relation, which corelates the propagation constant with frequency is obtained using the transfer matrix method in conjunction with Bloch's theorem. The results reveal the existence of multiple wide passbands in the low frequency range. These propagation characteristics are verified using a finite element model. The emergence of these multiple passbands is attributed to various bending modes of the pipe, and it is necessary to efficiently control them. In order to achieve both independent and simultaneous control of multiple passbands, the feasibility of deploying either a single or a two degree of freedom resonator at each span of the pipe is evaluated. As the positioning of resonators within a span governs their performance, to gain a deeper understanding of this, an iterative procedure is adopted wherein resonators are placed at each possible location in the span. A genetic algorithm-based optimization is then performed to arrive at the corresponding optimal parameters. The ideal location for placing a resonator to control each passband is the one that yields the best performance. Finally, the efficacy of the proposed control scheme is verified using Gaussian white noise as input. The dispersion relation and control schemes proposed herein not only provide insights into understanding the propagation behavior of flexural wave and their control in pipes, but also can be equally applied to other analogous periodic structures.

了解和控制管道振动是关键问题，因为它们会影响管道系统的可用性和性能。一种新的超材料概念可以用来控制这些振动。本文研究了弯曲波在与机架耦合的管道中的传播特性。利用传递矩阵法结合布洛赫定理，得到了传输常数与频率之间的色散关系。结果表明，在低频范围内存在多个宽通带。利用有限元模型验证了这些传播特性。这些多通带的出现是由于管道的各种弯曲模式造成的，需要对其进行有效的控制。为了实现对多个通带的独立和同时控制，评估了在管道的每个跨度上部署单个或两个自由度谐振器的可行性。由于谐振器在跨度内的位置决定了它们的性能，为了更深入地了解这一点，采用迭代过程，将谐振器放置在跨度内的每个可能位置。然后进行基于遗传算法的优化，得到相应的最优参数。放置谐振器以控制每个通带的理想位置是产生最佳性能的位置。最后，以高斯白噪声作为输入，验证了所提控制方案的有效性。本文提出的色散关系和控制方案不仅有助于理解弯曲波在管道中的传播特性及其控制，而且同样可以应用于其他类似的周期结构。