Thin-Walled Structures最新文献_第2页

Finite Tube Method for buckling analysis of tubular members using Fourier-approximation for the displacements 利用傅立叶位移近似法进行管状构件屈曲分析的有限管法

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-08 DOI: 10.1016/j.tws.2024.112672

Sándor Ádány , Benjamin W. Schafer

In this paper an efficient numerical method for the static analysis of cylindrical tubes is introduced. The method is designed for the linear buckling analysis of wind turbine support towers which are, most typically, built up from conical and/or cylindrical cans. Accordingly, the developed method uses cylindrical tube segments as elementary building blocks, along with specialized shape functions, and is named the Finite Tube Method. Within a tube segment the displacements are approximated by two-dimensional Fourier series. The curved nature of the surface is directly considered in the kinematic equations. The segments are joined and/or supported to the ground by constraint equations or by elastic links. In the current implementation internal stresses are determined in a simplified way: the circumferential stress distributions are calculated from the internal forces/moment by classic strength of material formulae, while the longitudinal distribution within each segment is quadratic. The considered internal forces/moments are: normal force, shear force, bending moment, and torsional moment. The internal forces can be arbitrarily combined. In the paper the underlying derivations are briefly summarized, then the method is demonstrated and validated by numerical examples, comparing the results to analytical and alternative numerical solutions. The authors are actively developing the method and will provide future work on utilization of the method for buckling mode identification and decomposition, as well as practical advancements to make the method a useful tool in the engineering design and analysis of wind turbine support towers.

本文介绍了一种用于圆柱管静态分析的高效数值方法。该方法专为风力涡轮机支撑塔架的线性屈曲分析而设计，风力涡轮机支撑塔架通常由圆锥形和/或圆柱形罐体构成。因此，所开发的方法使用圆柱形管段作为基本构件，同时使用专门的形状函数，并命名为 "有限管法"。在管段内，位移由二维傅里叶级数近似表示。运动方程中直接考虑了表面的弯曲性质。管段通过约束方程或弹性链接与地面连接和/或支撑。在当前的实施中，内应力是以简化的方式确定的：圆周应力分布是通过经典的材料强度公式从内力/力矩中计算出来的，而每个区段内的纵向应力分布是二次应力分布。考虑的内力/力矩包括：法向力、剪切力、弯矩和扭矩。这些内力可以任意组合。本文简要总结了基本推导，然后通过数值示例对该方法进行了演示和验证，并将结果与分析和其他数值解法进行了比较。作者正在积极开发该方法，并将在今后的工作中提供利用该方法进行屈曲模式识别和分解的方法，以及使该方法成为风力涡轮机支撑塔工程设计和分析的有用工具的实际进展。

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引用次数: 0

Localized stochastic dynamic solution for laminated coupled open conical-cylindrical cabin system based on the condensation method 基于凝结法的层状耦合开放式圆锥-圆柱机舱系统局部随机动态解法

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-08 DOI: 10.1016/j.tws.2024.112691

Chenchen Guo , Qingshan Wang , Tao Liu , Bin Qin

This paper proposed a technical solution for quickly and accurately solving the stochastic dynamic characteristics of laminated coupled open conical-cylindrical cabin system. On the basic of first-order shear deformation theory (FSDT), the two-dimensional spectral Chebyshev method was introduced to obtain a unified dynamic matrix that included laminated conical and cylindrical panels. The middle part of the cabin was selected as the target substructure, while the precise dynamic condensation theory was used as a tool to establish a local dynamic analysis model of the cabin system based on comprehensive consideration of complex boundary conditions, coupling conditions, random load excitation and other factors. From a numerical analysis perspective, the local-level dynamic responses obtained from the model were validated to match well with the global-level results from the finite element method. Based on this numerical validation, a dynamic parametric analysis scheme was proposed, focusing on the local dynamic characteristics of the target substructure. This scheme analyzed the impact of the structural parameters of the middle part of cabin on the dynamic behaviors of the cabin system, providing technical guidance for the design optimization of the cabin system in engineering applications.

本文提出了一种快速准确求解层压耦合开放式圆锥-圆柱机舱系统随机动态特性的技术方案。在一阶剪切变形理论（FSDT）的基础上，引入二维频谱切比雪夫方法，得到包含层叠圆锥板和圆柱板的统一动力矩阵。选取机舱中部作为目标下部结构，以精确动力凝聚理论为工具，在综合考虑复杂边界条件、耦合条件、随机载荷激励等因素的基础上，建立了机舱系统的局部动力分析模型。从数值分析的角度来看，模型得到的局部动态响应与有限元方法得到的全局结果相吻合。在数值验证的基础上，提出了一种动态参数分析方案，重点分析目标下部结构的局部动态特性。该方案分析了客舱中部结构参数对客舱系统动态行为的影响，为客舱系统在工程应用中的优化设计提供了技术指导。

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引用次数: 0

Research on combined damage characteristics of underwater armor-piercing and explosion based on supercavitating projectile 基于超空泡弹丸的水下穿甲与爆炸组合破坏特性研究

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-07 DOI: 10.1016/j.tws.2024.112685

Gong Han-xin , Tang Kui , Kong Ling-quan , Wang Jin-xiang , Ma Yi-ming , Hao Xu-long , Li Heng

Recent studies of supercavitating projectiles primarily focus on the formation and evolution of the cavity, as well as its underwater ballistic characteristics, while neglecting the terminal damage effects. Little attention has been given to exploring the combined damage effects of armor-piercing-explosion supercavitating projectiles (APESP). Therefore, this study comparatively analyzes the response processes and failure modes of an underwater aluminum alloy cylindrical shell target under the action of three different types of loads: armor piercing, explosion, and combined armor-piercing and explosion. This study investigates the underwater combined damage mechanisms of the APESP, clarifies each damage phase under the combined effect, discusses the advantages of damage resulting from the combined armor-piercing and explosion effect based on the target responses and damage modes, and explores the reasons for dissipation of explosion energy. The results show that: the APESP combines localized point damage characteristics of armor piercing with overall surface damage features of underwater explosion. Depending on load stages and target responses, the target response process under the action of the APESP can be divided into the hydrodynamic ram phase, penetration phase, shock wave phase, stable vibration phase, and bubble pulsation phase. The entire physical system can be abstracted as a low-frequency series spring system (equivalent to bubble pulsation frequency) with high-frequency external energy input, based on the energy relationship of the medium and the structure. The concept of the 'blower effect' is proposed based on target behavior during the stable vibration phase. Following the application of different loads, the plastic deformation of the target in a stable state is ranked as: underwater explosion > combined armor-piercing and explosion > underwater armor piercing. Supercavity, shell casing and penetration hole will cause the dissipation of explosion energy.

最近对超空泡弹的研究主要集中在空腔的形成和演变及其水下弹道特性上，而忽略了末端破坏效应。人们很少关注穿甲-爆炸超空泡弹（APESP）的综合损伤效应。因此，本研究比较分析了水下铝合金圆柱形炮弹目标在三种不同载荷（穿甲、爆炸以及穿甲和爆炸组合载荷）作用下的响应过程和破坏模式。本研究探讨了 APESP 的水下组合破坏机理，明确了组合效应下的各个破坏阶段，根据目标响应和破坏模式讨论了穿甲和爆炸组合效应导致破坏的优势，并探讨了爆炸能量耗散的原因。结果表明：APESP 结合了穿甲的局部点损伤特征和水下爆炸的整体面损伤特征。根据载荷阶段和目标响应，APESP 作用下的目标响应过程可分为水动力冲撞阶段、穿透阶段、冲击波阶段、稳定振动阶段和气泡脉动阶段。根据介质和结构的能量关系，可将整个物理系统抽象为一个低频串联弹簧系统（相当于气泡脉动频率）与高频外部能量输入系统。根据稳定振动阶段的目标行为，提出了 "鼓风机效应 "的概念。在施加不同载荷后，目标在稳定状态下的塑性变形分为：水下爆炸；穿甲与爆炸相结合；水下穿甲。超空腔、弹壳和贯穿孔会导致爆炸能量耗散。

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引用次数: 0

A homogenization model for multiple buckling response of axially compressed cellular cylindrical shells 轴向压缩蜂窝圆柱壳多重屈曲响应的均质化模型

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-07 DOI: 10.1016/j.tws.2024.112637

Fangle Qi, Linghui He, Yong Ni

Pattern transformation in periodic cellular structures induces significant property changes under specific external stimuli, resulting in unusual mechanical behavior. This paper proposes an efficient homogenization method for predicting multiple buckling responses of cellular cylindrical shells composed of such pattern-transformation metamaterial. FEM simulations reveal four distinct buckling modes and three kinds of post-buckling processes, achieved through controlled adjustments in the ratio of cylindrical shell thickness to the radius and structural porosity. An efficient homogenization method with the local buckling in the cellular cylindrical shell modeled as an equivalent plasticity in the homogenized shell enables us to predict the critical buckling stress and the post-buckling morphology in good agreement with FEM simulations, analytical analysis, and experiments. The derived solution for the critical buckling load of the cellular cylindrical shells provides practical insights for designing and applying such cylindrical cellular structures.

在特定的外部刺激下，周期性蜂窝结构中的图案变换会诱发显著的性质变化，从而导致不寻常的力学行为。本文提出了一种高效的均质化方法，用于预测由这种图案变换超材料组成的蜂窝圆柱壳的多重屈曲响应。有限元模拟揭示了四种不同的屈曲模式和三种屈曲后过程，这些都是通过控制调整圆柱壳厚度与半径之比以及结构孔隙率实现的。我们采用了一种高效的均质化方法，将蜂窝圆柱形外壳中的局部屈曲模拟为均质化外壳中的等效塑性，从而预测了临界屈曲应力和屈曲后形态，与有限元模拟、分析和实验结果十分吻合。推导出的蜂窝圆柱壳临界屈曲载荷解决方案为设计和应用此类圆柱蜂窝结构提供了实用见解。

引用次数: 0

Microstructure and mechanical properties of Mg-Nd-Zn-Zr alloy fabricated by TIG-based wire – Arc directed energy deposition with pulsed current 利用脉冲电流氩弧焊线-弧定向能沉积技术制造的 Mg-Nd-Zn-Zr 合金的微观结构和力学性能

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-07 DOI: 10.1016/j.tws.2024.112684

Ke Wu , Xinge Zhang , Wenquan Wang , Jingwei Liang , Xin Zheng , Faming Shen , Xudong Liang , Zhihui Zhang

In this study, the Mg-Nd-Zn-Zr alloy thin-wall specimens were prepared by tungsten inert gas (TIG) based wire-arc directed energy deposition (WA-DED) with different pulsed currents. The arc characteristics of different pulsed current frequents were observed. The microstructures, and mechanical properties of as-deposited (AD), 5 Hz, 10 Hz, 15 Hz, and 20 Hz specimens were systematically analyzed and evaluated. The uniformly equiaxed crystals with random grain orientations and intergranular network Mg-Nd-Zn eutectics were found in the WA-DED fabricated Mg-Nd-Zn-Zr alloy thin-wall specimens. No significant voids were found. The microstructures were regulated, and the mechanical properties were improved by adjusting the pulsed current frequency. The 10 Hz specimen had the optimal microstructure with an average grain size of 10.35 μm. Concurrently, the 10 Hz specimen exhibits excellent strength-ductility synergy and isotropic, benefiting from the finely equiaxed crystals. The average microhardness of the 10 Hz specimen was 68.51 HV_0.2, and the ultimate tensile strengths in the building and traveling directions were 223 MPa and 229.7 MPa, respectively, and the yield strengths in the building and traveling directions were 138.3 MPa and 145.3 MPa, respectively. Notably, the elongations in the building and traveling directions of the 10 Hz specimen were 16.8 % and 17.4 %, respectively. The local strain evolution and fracture surfaces of AD and 10 Hz specimens in the building and traveling directions were observed. The mechanisms of grain refinement and mechanical properties improvement were revealed.

本研究采用基于钨惰性气体（TIG）的线弧定向能沉积（WA-DED）技术，以不同的脉冲电流制备了 Mg-Nd-Zn-Zr 合金薄壁试样。观察了不同脉冲电流频率下的电弧特性。系统分析和评估了原沉积 (AD)、5 Hz、10 Hz、15 Hz 和 20 Hz 试样的微观结构和机械性能。在 WA-DED 制造的 Mg-Nd-Zn-Zr 合金薄壁试样中发现了具有随机晶粒取向的均匀等轴晶粒和晶间网络 Mg-Nd-Zn 共晶。没有发现明显的空隙。通过调节脉冲电流频率，微观结构得到了调节，力学性能也得到了改善。10 Hz 试样具有最佳微观结构，平均晶粒大小为 10.35 μm。同时，10 赫兹试样具有优异的强度-电导率协同性和各向同性，这得益于精细的等轴晶粒。10 Hz 试样的平均显微硬度为 68.51 HV0.2，建筑方向和行进方向的极限抗拉强度分别为 223 兆帕和 229.7 兆帕，建筑方向和行进方向的屈服强度分别为 138.3 兆帕和 145.3 兆帕。值得注意的是，10 Hz 试样在建筑方向和行进方向的伸长率分别为 16.8 % 和 17.4 %。观察了 AD 和 10 Hz 试样在建筑和行进方向上的局部应变演变和断裂面。揭示了晶粒细化和力学性能改善的机制。

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引用次数: 0

Enhancing shear strength in hybrid metal-composite single-lap joints using Z-pins fabricated via fused filament fabrication 利用熔融长丝制造工艺制作的 Z 形销增强混合金属复合材料单搭接接头的剪切强度

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-06 DOI: 10.1016/j.tws.2024.112680

Run Chen , Qixin Zhao , Mengjia Li , Sisi Wang , Yuan Zhao , Xiping Li , Shiju E , Linlin Wang

This paper investigates the interfacial shear strength of hybrid metal-composite single-lap joints (SLJs) reinforced with stainless steel Z-pins fabricated by fused filament fabrication (FFF). The joints were created by 3D printing an orthogonal array of 2 mm diameter steel Z-pins onto a steel substrate using FFF. The Z-pins were then embedded into a basalt fibre (BF)-fabric/epoxy resin composite using the Ultrasonically Assisted Z-Fibre™ (UAZ) method to form a high-strength and tough interface. The results demonstrate that steel Z-pins produced via FFF effectively enhance the shear strength of the hybrid metal-composite SLJs, significantly improving joint performance. The study also explores the influence of Z-pin volume fraction and embedding height on SLJ shear strength. It was found that higher volume fractions and greater embedding heights of the Z-pins contribute to the increased shear strength. Compared to unreinforced joints, the maximum shear strength of the steel Z-pin reinforced joints increased by 120.1 %. This enhancement is attributed to the effective energy absorption mechanisms, primarily facilitated by the frictional pull-out, plastic deformation and shear fracture of Z-pins accompanied by the formation of ductile dimples. These mechanisms suppress crack propagation and improve joint integrity. This study presents an innovative approach for fabricating hybrid metal-composite joints with enhanced toughness and strength.

本文研究了采用熔融长丝制造（FFF）技术制造的、用不锈钢 Z 形销加固的混合金属复合材料单搭接接头（SLJ）的界面剪切强度。接头是通过使用 FFF 将直径为 2 毫米的正交阵列钢 Z 形销三维打印到钢基板上制成的。然后使用超声辅助 Z-Fibre™（UAZ）方法将 Z 形销嵌入玄武岩纤维（BF）-织物/环氧树脂复合材料中，以形成高强度和坚韧的界面。结果表明，通过 FFF 生产的钢 Z 针能有效提高混合金属复合材料 SLJ 的剪切强度，显著改善接头性能。研究还探讨了 Z 销的体积分数和嵌入高度对 SLJ 剪切强度的影响。研究发现，Z 销的体积分数越高、嵌入高度越大，剪切强度就越高。与未加固的接头相比，钢 Z 形销加固接头的最大剪切强度提高了 120.1%。这种提高归功于有效的能量吸收机制，主要是由 Z 形销的摩擦拉出、塑性变形和剪切断裂以及韧性凹痕的形成所促进的。这些机制可抑制裂纹扩展，提高连接完整性。本研究提出了一种制造具有更高韧性和强度的混合金属复合材料接头的创新方法。

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引用次数: 0

A comprehensive study of beam modal functions in the free vibration analysis of cylindrical shells: Critical examination on the applicability to the clamped-free boundary condition 圆柱形壳体自由振动分析中梁模态函数的综合研究：对无夹钳边界条件适用性的严格审查

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-05 DOI: 10.1016/j.tws.2024.112674

Ganghui Xu, Changsheng Zhu

Over the past few decades, approximate methods that can provide solutions of sufficient accuracy have received considerable attention in the free vibration analysis of cylindrical shells, where a great deal of studies adopted the beam modal functions as the trial functions for the axial mode shapes of cylindrical shells. Nevertheless, most studies were restricted to the application of single term beam modal function and failed to simulate elastic boundary conditions of cylindrical shells, while the accuracy of the corresponding methods has recently sparked significant controversy, especially for cylindrical shells under the clamped-free boundary condition. This paper presents a comparative study of three forms of beam modal functions in the free vibration analysis of cylindrical shells, one of which is proposed for the first time to simulate elastic boundary conditions of cylindrical shells. A unified model is developed using the general Rayleigh–Ritz method, incorporating the breathing modes with circumferential orders being zero, and four types of commonly used thin shell theories, namely the Donnell, Reissner, Love, and Sanders theories. From both perspectives of natural frequencies and mode shapes, numerical results are validated by comparison with those existing in the literature and those calculated from the finite element method (FEM). The results not only clarify the distinction of different forms of beam modal functions used in the Rayleigh-Ritz method, but also provide explanations for the controversy raised in recent studies. Furthermore, the unified formulations can be extended to vibration analysis of various forms of shell structures, and can also be helpful to the vibration analysis of beams and plates with elastic boundary conditions.

在过去的几十年中，能够提供足够精确解的近似方法在圆柱形壳自由振动分析中受到了广泛关注，其中大量研究采用梁模态函数作为圆柱形壳轴向模态振型的试验函数。然而，大多数研究局限于单项梁模态函数的应用，未能模拟圆柱壳的弹性边界条件，而相应方法的准确性最近引发了很大争议，特别是对于无夹紧边界条件下的圆柱壳。本文对圆柱壳自由振动分析中的三种梁模态函数形式进行了比较研究，并首次提出了其中一种模拟圆柱壳弹性边界条件的梁模态函数。利用一般雷利-里兹方法，结合周向阶数为零的呼吸模态，以及四种常用的薄壳理论，即 Donnell、Reissner、Love 和 Sanders 理论，建立了一个统一的模型。从固有频率和模态振型两个角度，通过与文献中的结果和有限元法（FEM）计算的结果进行比较，对数值结果进行了验证。结果不仅澄清了雷利-里兹方法中使用的不同形式梁模态函数的区别，还为近期研究中出现的争议提供了解释。此外，统一公式可扩展到各种形式壳体结构的振动分析，对具有弹性边界条件的梁和板的振动分析也有帮助。

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引用次数: 0

Web shear buckling of steel-concrete composite girders – advanced numerical analysis 钢-混凝土复合梁的腹板剪切屈曲--高级数值分析

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-05 DOI: 10.1016/j.tws.2024.112671

Mehmed Numanović , Markus Knobloch

Load-bearing capacity of plate girders, often used in design of bridges and high-rise buildings, is limited by the shear capacity of connected slender plate elements subjected to shear buckling. To quantify this, experimental investigations on five large-scale steel and steel-concrete composite plate girders loaded solely in shear, with a minimal influence of bending moments, have been conducted and evaluated. In this paper, the phenomenon of web shear buckling is investigated within the numerical analysis using the ABAQUS Software. An advanced numerical model has been developed and results validated against existing experimental findings. One of the focal points of this study represents the methodology of developing such a comprehensive numerical model, implementation of suitable analysis procedures, material models, boundary conditions, finite elements and interactions, in order to correctly replicate the observed response in the tests. In addition, case studies tackling the influence of web slenderness, aspect ratio, initial imperfections, shear connection and concrete classes on the structural-mechanical behavior of steel-concrete composite girders in shear as well as the applicability and suitability of the existing analytical model are also presented and analyzed.

板梁通常用于桥梁和高层建筑的设计，其承载能力受限于连接的细长板元件受剪屈曲的抗剪能力。为了量化这一点，我们对五种大型钢板梁和钢-混凝土复合板梁进行了实验研究和评估，这些板梁只承受剪力，受弯矩的影响很小。本文使用 ABAQUS 软件在数值分析中研究了腹板剪切屈曲现象。开发了一个先进的数值模型，并根据现有的实验结果对结果进行了验证。本研究的重点之一是开发这种综合数值模型的方法、实施适当的分析程序、材料模型、边界条件、有限元和相互作用，以便正确复制试验中观察到的响应。此外，还介绍并分析了腹板细长、长宽比、初始缺陷、剪力连接和混凝土等级对钢-混凝土复合梁在剪力作用下的结构-力学行为的影响，以及现有分析模型的适用性和适宜性。

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引用次数: 0

Shock mitigation and failure mechanism of copper foam/paraffin phase change reinforced composites 泡沫铜/石蜡相变增强复合材料的减震和失效机理

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-05 DOI: 10.1016/j.tws.2024.112673

Jingjing Song , Yuliang Lin , Minzu Liang , Wen Liang , Jiakai Guo , Yuwu Zhang

Copper foam/paraffin phase change reinforced composites (CPPC) were fabricated using vacuum immersion technology to address the pressing need for phase change reinforced composite applications. Experiments were conducted to explore the influence of strain rate and relative density of the matrix material on the mechanical properties of the CPPC under both quasi-static and dynamic conditions. A 3D-Voronoi model of the CPPC was developed with randomly varying relative density, based on real porous metal foam and utilizing graphical parametric design tools. The mechanical behavior of the CPPC under impact loading was studied, focusing on deformation, energy absorption, and damage mechanisms. Comparison and analysis of stress-strain curves and deformation modes were performed using experimental and modeling data. The shear failure modes of CPPC under quasi-static compression include 'X-shaped fracture,' 'blocky spalling,' or '45° parallel fracture,' depending on the relative density of the copper foam matrix. The addition of paraffin effectively improved the energy-absorbing properties of copper foam. As the relative density of the copper foam matrix increased, the enhancement in energy absorption became more pronounced, while the improvement in modulus and yield strength decreased. The composite exhibited an 83 % increase in specific energy absorption compared to copper foam alone, with the paraffin filler absorbing 69 % of the total energy during impact loading. The CPPC acted as a mechanical filter through stress wave reflection and transmission attenuation. The investigation into the shock mitigation and failure mechanisms of CPPC could offer valuable insights for the design of functional composites. Furthermore, it could inspire the creation of impact-resistant and heat dissipation structures for electronic devices.

为了满足相变增强复合材料应用的迫切需要，我们采用真空浸泡技术制造了泡沫铜/石蜡相变增强复合材料（CPPC）。实验探索了在准静态和动态条件下，基体材料的应变率和相对密度对 CPPC 机械性能的影响。以真实的多孔金属泡沫为基础，利用图形参数化设计工具，建立了随机改变相对密度的 CPPC 三维-Voronoi 模型。研究了 CPPC 在冲击载荷下的机械行为，重点关注变形、能量吸收和损坏机制。利用实验和建模数据对应力-应变曲线和变形模式进行了比较和分析。根据泡沫铜基体的相对密度，CPPC 在准静态压缩下的剪切破坏模式包括 "X 形断裂"、"块状剥落 "或 "45° 平行断裂"。添加石蜡可有效改善泡沫铜的吸能特性。随着泡沫铜基体相对密度的增加，能量吸收性能的提高更加明显，而模量和屈服强度的提高则有所下降。与单独的泡沫铜相比，复合材料的比能量吸收提高了 83%，其中石蜡填料吸收了冲击载荷期间总能量的 69%。CPPC 通过应力波反射和传输衰减起到了机械过滤器的作用。对 CPPC 的冲击缓解和失效机制的研究可为功能复合材料的设计提供宝贵的见解。此外，它还能启发人们为电子设备创造抗冲击和散热结构。

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引用次数: 0

Physics-informed radial basis networks for force finding of cable domes 用于电缆穹顶测力的物理信息径向基网络

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-05 DOI: 10.1016/j.tws.2024.112675

Mingliang Zhu , Jin Wang , Jiamin Guo

The stiffness of cable dome structures is entirely derived from the prestress in their cables and struts, making force-finding a critical step in their design. However, traditional force-finding methods are often complex to implement and have limited applicability. To address these challenges, this paper establishes a general force-finding framework for cable domes based on physics-informed radial basis networks (PIRBN), utilizing neural network techniques to achieve an efficient and reliable force-finding process. Additionally, a loss function is derived that incorporates the physical characteristics of cable domes from the perspective of structural stiffness. Case studies on three types of cable domes were conducted, and the hyperparameter tuning of the network model was simplified using the Optuna hyperparameter optimization method. The results show that PIRBN is suitable for force-finding analysis in both single and multiple prestress mode cable domes, considering the effects of external loads, and provides high computational efficiency and broad applicability.

缆索穹顶结构的刚度完全来自其缆索和支柱中的预应力，因此测力是缆索穹顶结构设计的关键步骤。然而，传统的测力方法往往实施复杂，适用性有限。为了应对这些挑战，本文基于物理信息径向基网络（PIRBN），利用神经网络技术建立了缆索穹顶的一般测力框架，以实现高效可靠的测力过程。此外，还从结构刚度的角度推导出了一个包含缆索穹顶物理特性的损失函数。对三种类型的缆索穹顶进行了案例研究，并使用 Optuna 超参数优化方法简化了网络模型的超参数调整。结果表明，考虑到外部荷载的影响，PIRBN 适用于单预应力模式和多预应力模式索穹的寻力分析，具有较高的计算效率和广泛的适用性。

引用次数: 0