Thin-Walled Structures最新文献_第3页

Self-healing effect on the impact-resistance of hybrid stitch toughening CFRP composites: Experimental and numerical study 自愈合对混合缝合增韧 CFRP 复合材料抗冲击性能的影响：实验和数值研究

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-04 DOI: 10.1016/j.tws.2024.112635

Zhenzhen Zhang , Yutong Liu , Ying Tie , Yuliang Hou , Cheng Li

The self-healing effect on the impact-resistance has been investigated for hybrid stitch toughening CFRP composites using multiscale modeling. The stitches made of the healing agent, poly ethylene-co-methacrylic acid (EMAA), facilitate the repair of delamination damages via a self-healing process. The other stitches, fabricated from carbon fiber, contribute to the enhancement of interlaminar toughness. Considering the local structural features adjacent to the stitches, an equivalent fiber-embedded laminate (EFEL) cell is established to characterize the mesoscale behavior. A modified constitutive model is developed to accurately describe the deformation modes of the EFEL cell. Subsequently, a macroscale model is constructed by directly extending the EFEL cells. The self-healing of the impact-resistance is numerically explored through multiple low-velocity impact (LVI) tests. The proposed modeling approach enables a prediction error less than 8.4% and the computation time of approximately 17.3 h (1036 min), demonstrating the high accuracy and efficiency. After the self-healing process, the peak impact forces of the LVI specimens increase, while decreases in absorbed energy are observed. Moreover, the healed specimens exhibit fewer damaged elements and a smoother damaged surface compared with the unhealed ones. It demonstrates that the EMAA healing agent possesses the capability to improve the impact-resistance of hybrid stitch toughening CFRP composites.

通过多尺度建模，研究了混合缝合增韧 CFRP 复合材料对抗冲击性的自修复效应。由愈合剂聚乙二醇-甲基丙烯酸（EMAA）制成的缝合线可通过自愈合过程促进分层损伤的修复。其他缝合线由碳纤维制成，有助于增强层间韧性。考虑到缝合线附近的局部结构特征，建立了一个等效纤维嵌入层压板（EFEL）单元来描述中尺度行为。为准确描述 EFEL 单元的变形模式，开发了一个改进的构成模型。随后，通过直接扩展 EFEL 单元构建了宏观模型。通过多次低速冲击（LVI）试验，对抗冲击性能的自愈进行了数值探索。所提出的建模方法使预测误差小于 8.4%，计算时间约为 17.3 小时（1036 分钟），体现了高精度和高效率。自愈合过程结束后，LVI 试样的峰值冲击力增加，而吸收的能量减少。此外，与未愈合试样相比，愈合试样的受损元素更少，受损表面更光滑。这表明 EMAA 愈合剂具有提高混合缝合增韧 CFRP 复合材料抗冲击性能的能力。

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引用次数: 0

Weak form quadrature shell elements based on absolute nodal coordinate formulation 基于绝对节点坐标公式的弱形式正交壳元素

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-04 DOI: 10.1016/j.tws.2024.112670

Zixuan He, Huayi Li, Hongzhi Zhong

Weak form quadrature elements for moderately thick shells with arbitrary initial configurations are developed under the framework of continuum mechanics and the absolute nodal coordinate formulation (ANCF). Locking problems of shell analysis are discussed. Nonlinear analysis of various shell structures is conducted. The joint constraint equations for shells with discontinuous slopes are established. Five examples encompassing static and dynamic shell analysis, post-buckling analysis of shells, as well as analysis of shells with discontinuous mid-surface slopes are examined to assess the performance of the proposed elements. Satisfactory results are obtained, validating the efficacy of the proposed elements.

在连续介质力学和绝对节点坐标公式（ANCF）的框架下，开发了用于具有任意初始构型的中等厚度壳体的弱形式二次元。讨论了壳分析的锁定问题。对各种壳体结构进行了非线性分析。建立了不连续斜坡壳体的联合约束方程。研究了五个实例，包括静态和动态壳体分析、壳体的后屈曲分析以及具有不连续中表面斜坡的壳体分析，以评估所提出的元素的性能。结果令人满意，验证了所提元素的有效性。

引用次数: 0

A 3D shell model for static and free vibration analysis of multilayered magneto-elastic structures 用于多层磁弹性结构静态和自由振动分析的三维壳体模型

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-04 DOI: 10.1016/j.tws.2024.112620

S. Brischetto, D. Cesare

In this paper, an exact 3D coupled magneto-elastic shell model for static and free vibration analysis of multilayered piezomagnetic smart structures is presented. The introduction of the mixed curvilinear orthogonal reference system (

α, β, z

) allows investigations of plates, cylindrical shells, cylinders and spherical shells as actuators or sensors and also in free vibration conditions. The present exact 3D coupled shell model is composed of four second-order differential equations whose primary variables are the three displacements

u

,

v

and

w

and the magnetic potential

ψ

. Displacements, stresses, strains, magnetic potential, magnetic induction and circular frequency values are computed to understand the behaviour of piezomagnetic smart structures. The resolution method adopted for the present 3D magneto-elastic problem is based on harmonic forms in

α

and

β

in-plane directions and the exponential matrix method in the

z

direction. Simply supported one-layered/multilayered structures with

0 °

or

90 °

orthotropic angles have been analysed. The results section is divided into a first part related to the validation of the proposed 3D model and a second part where new benchmark cases are presented and discussed. Different lamination schemes, load boundary conditions, geometries and materials are studied. Magneto-elastic coupling, thickness and material layer effects are discussed for thin and thick structures. The main novelty of the present exact 3D coupled magneto-elastic shell model stands in the ability to analyse several geometries and multilayered configurations embedding piezomagnetic materials under the action of different boundary loads via a general mathematical formulation.

本文提出了一种精确的三维耦合磁弹性壳体模型，用于多层压磁智能结构的静态和自由振动分析。通过引入混合曲线正交参考系（α,β,z），可以研究作为致动器或传感器的板、圆柱壳、圆柱和球壳以及自由振动条件。本精确三维耦合壳体模型由四个二阶微分方程组成，其主要变量为三个位移 u、v 和 w 以及磁势 ψ。通过计算位移、应力、应变、磁势、磁感应强度和圆周频率值，可以了解压磁智能结构的行为。本三维磁弹性问题采用的解析方法基于平面方向上 α 和 β 的谐波形式以及 Z 方向上的指数矩阵法。分析了各向同性角为 0°或 90°的单层/多层简支撑结构。结果部分分为第一部分和第二部分，第一部分是对提出的三维模型的验证，第二部分是对新基准案例的介绍和讨论。研究了不同的层压方案、载荷边界条件、几何形状和材料。讨论了薄结构和厚结构的磁弹性耦合、厚度和材料层效应。本精确三维耦合磁弹性壳体模型的主要新颖之处在于，它能够通过通用数学公式分析不同边界载荷作用下嵌入压磁材料的多种几何形状和多层结构。

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引用次数: 0

Shear performance prediction for corrugated steel web girders based on machine-learning algorithms 基于机器学习算法的波形钢腹板梁剪切性能预测

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-04 DOI: 10.1016/j.tws.2024.112668

Yong Liu , Wei Ji , Jieqi Li , ShiBo Liu , Wenjuan Yang

This study aimed to predict the shear strength of corrugated steel web girders (CSWGs) by developing a new method based on four machine-learning (ML) algorithms, namely the support vector machine, artificial neural network, random forest, and XGBoost. Based on the acquired experimental and numerical data, a database containing 552 samples was constructed to train and test the ML models. A five-fold cross-validation approach was adopted during training to prevent model overfitting. A RandomizedSearchCV was used to optimize the hyperparameters of each model. The performance of the trained models was evaluated using four performance metrics, and the results revealed that the coefficients of determination (R²) of all ML models exceeded 0.97 when used on both training and validation sets, demonstrating the excellent performance of the ML models in predicting the shear strength of CSWGs. Additionally, the implemented ML models outperformed existing design codes and empirical formulae. The XGBoost model yielded the best prediction results with an R² of 0.999, mean absolute error of 44.98 kN, root-mean-square error of 66.67 kN, and mean absolute percentage error of 2.1 %. By using the Shapley additive explanation to derive a visual, quantitative explanation of the XGBoost model, the yield strength, web thickness, and web height were identified as the most critical factors affecting the shear strength of CSWGs, and their average absolute Shapley values accounted for approximately 91.45 % of the total value. The ML models implemented in this study provide a promising new approach for pre-designing and verifying the stability of CSWGs.

本研究旨在通过开发一种基于四种机器学习（ML）算法（即支持向量机、人工神经网络、随机森林和 XGBoost）的新方法来预测波形钢腹板梁（CSWG）的抗剪强度。根据获得的实验和数值数据，构建了一个包含 552 个样本的数据库，用于训练和测试 ML 模型。在训练过程中采用了五倍交叉验证方法，以防止模型过拟合。使用 RandomizedSearchCV 来优化每个模型的超参数。结果显示，所有 ML 模型在训练集和验证集上的决定系数（R2）都超过了 0.97，这表明 ML 模型在预测 CSWG 的剪切强度方面表现出色。此外，已实施的 ML 模型的性能优于现有的设计规范和经验公式。XGBoost 模型的预测结果最好，R2 为 0.999，平均绝对误差为 44.98 kN，均方根误差为 66.67 kN，平均绝对百分比误差为 2.1%。通过使用 Shapley 加法解释得出 XGBoost 模型的可视化定量解释，屈服强度、腹板厚度和腹板高度被确定为影响 CSWG 剪切强度的最关键因素，其平均绝对 Shapley 值约占总值的 91.45%。本研究采用的 ML 模型为预先设计和验证 CSWG 的稳定性提供了一种很有前途的新方法。

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引用次数: 0

An origami-wheeled robot with variable width and enhanced sand walking versatility 宽度可变的折纸轮式机器人，增强了沙地行走的多功能性

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-02 DOI: 10.1016/j.tws.2024.112645

Jie Liu , Zufeng Pang , Zhiyong Li , Guilin Wen , Zhoucheng Su , Junfeng He , Kaiyue Liu , Dezheng Jiang , Zenan Li , Shouyan Chen , Yang Tian , Yi Min Xie , Zhenpei Wang , Zhuangjian Liu

Robots inspired by origami that offer several benefits, including being lightweight, requiring less assembly, and possessing remarkable deformability, have drawn a lot of interest. However, the existing origami-inspired robots are usually of limited functionalities and developing feature-rich robots is very challenging. Here, we report an origami-wheeled robot (OriWheelBot) with exceptional mobility for sand walking and a changing width. Origami wheels created using Miura origami permit the OriWheelBot to alter wheel width over obstacles. We derive the variable-width and diameter analytical models of the origami wheel, assuming rigid-folding, which has been confirmed by testing. An enhanced variant, dubbed iOriWheelBot, is additionally being developed to autonomously determine the obstacle's breadth. Based on the width of the channel between the barriers, three actions will be executed: direct pass, variable width pass, and direct return. Sand-pushing is more suitable for walking on the sand than sand-digging, which is the other of the two motion mechanisms that we have identified. Many aspects of sand walking, including carrying loads, walking on a slope, climbing a slope, and negotiating sand pits, small rocks, and sand traps, have been methodically investigated. The OriWheelBot can climb a 17-degree sand incline, vary its width by 40 %, and have a loading-carrying ratio of 66.7 % on flat sand. Rescue operations in disaster areas and planetary subsurface exploration can benefit from the OriWheelBot.

受折纸启发的机器人具有多种优点，包括重量轻、组装要求低、可变形性强等，因此备受关注。然而，现有的折纸启发机器人通常功能有限，开发功能丰富的机器人非常具有挑战性。在此，我们报告了一种折纸轮式机器人（OriWheelBot），它在沙地行走时具有超强的机动性，而且宽度可以改变。使用三浦折纸制作的折纸轮子允许 OriWheelBot 在遇到障碍物时改变轮子宽度。我们推导出折纸轮的可变宽度和直径分析模型，并假设其为刚性折叠，这一点已通过测试得到证实。此外，我们还开发了一种增强型机器人，被称为 iOriWheelBot，能够自主确定障碍物的宽度。根据障碍物之间通道的宽度，将执行三种操作：直接通过、变宽通过和直接返回。与我们确定的两种运动机制中的另一种--挖沙相比，推沙更适合在沙地上行走。我们已对沙地行走的许多方面进行了有条不紊的研究，包括承载负荷、在斜坡上行走、爬坡，以及在沙坑、小石头和沙坑中穿行。OriWheelBot可以爬上17度的沙坡，其宽度变化幅度为40%，在平坦的沙地上的负重率为66.7%。灾区救援行动和行星地下勘探都将受益于 OriWheelBot。

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引用次数: 0

Oscillating laser-arc hybrid additive manufacturing of aluminum alloy thin-wall based on synchronous wire-powder feeding 基于同步送丝送粉的铝合金薄壁振荡激光-电弧混合快速成型技术

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-02 DOI: 10.1016/j.tws.2024.112665

Yunfei Meng, Qianxi Yu, Xu Wu, Xiaohan Guo, Ziheng Yang, Lidong Xu, Hui Chen

Synchronous wire-powder feeding was adopted to overcome the poor mechanical properties of aluminum alloy thin-wall caused by limited filling composition in wire-based laser-arc hybrid additive manufacturing. The results showed that the optimized Mg powder feeding improved the droplet transfer into a fine spray mode with reduced transition time by 18 %. Moreover, not only the effective width coefficient of thin-wall increased from 89 % to 95 %, but also the subsequent machining allowance reduced from 1.25 to 0.48 mm. The synchronous wire-powder feeding improved the formation accuracy by 61.6 %. Although the deposition microstructure was mainly composed of dendrites with obvious direction and increased average grain size by 54 %, a new Mg₂Si strengthened phase was also found. The ultimate tensile strength of thin-wall was increased by 12 % from 227.3 to 255.5 MPa. The related evolution mechanisms of deposition stability and mechanical properties by optimized powder feeding on the hybrid additive manufacturing were mainly discussed.

采用线材-粉末同步进给的方法克服了线材激光-电弧混合增材制造中由于填充成分有限而导致的铝合金薄壁力学性能差的问题。结果表明，优化的镁粉进给改善了液滴向精细喷雾模式的转移，过渡时间缩短了 18%。此外，不仅薄壁的有效宽度系数从 89% 提高到 95%，而且后续加工余量也从 1.25 mm 减少到 0.48 mm。线-粉同步进给使成形精度提高了 61.6%。虽然沉积微观结构主要由方向明显的树枝状晶组成，平均晶粒大小增加了 54%，但也发现了新的 Mg2Si 强化相。薄壁的极限抗拉强度从 227.3 兆帕提高到 255.5 兆帕，提高了 12%。主要讨论了优化粉末进料在混合快速成型过程中沉积稳定性和力学性能的相关演变机制。

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引用次数: 0

Research on damage repair and high-velocity impact characteristics of thermoplastic composites 热塑性复合材料的损伤修复和高速冲击特性研究

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-01 DOI: 10.1016/j.tws.2024.112663

Feng Jin, Lulu Liu, Xinying Zhu, Zhihao Xie, Wei Chen

Low-velocity impact (LVI) can result in imperceptible damage to carbon fiber reinforced thermoplastic composites (CFRTP) laminates during service, leading to a reduction in structural strength. The thermal repair of damaged CFRTP laminates is conducted using the repairability of thermoplastic resin at high temperatures. However, the high-velocity impact characteristics of CFRTP laminates following thermal repair remain uncertain. This study examines CFRTP laminates made of two different materials (CF/PEEK and CF/PPS) with varying levels of low-velocity impact damage, and investigates the thermal repair process. A comparative experimental analysis examined the high-speed impact characteristics of CFRTP laminates under varying conditions. The results indicate that CF/PEEK laminates consistently exhibit superior compressive properties and impact resistance compared to CF/PPS laminates under similar conditions. Following damage from low-velocity impact, the compressive properties and high-velocity impact resistance of CFRTP laminates decrease, with CF/PPS laminates typically showing a lower performance retention rate. However, the thermal repair process proposed in this study significantly enhances the performance of CF/PPS laminates. Moreover, the degree of performance healing in CF/PPS laminates is consistently higher than that in CF/PEEK laminates, which is closely related to the semi-crystalline nature of PEEK resin.

在使用过程中，低速冲击（LVI）会对碳纤维增强热塑性复合材料（CFRTP）层压板造成难以察觉的损坏，导致结构强度降低。受损 CFRTP 层压板的热修复是利用热塑性树脂在高温下的可修复性进行的。然而，热修复后 CFRTP 层压板的高速冲击特性仍不确定。本研究考察了由两种不同材料（CF/PEEK 和 CF/PPS）制成的 CFRTP 层压板的不同低速冲击损伤程度，并研究了热修复过程。对比实验分析检验了 CFRTP 层压板在不同条件下的高速冲击特性。结果表明，在类似条件下，与 CF/PPS 层压板相比，CF/PEEK 层压板始终表现出更优越的抗压性能和抗冲击性能。低速冲击造成损坏后，CFRTP 层压板的压缩性能和高速冲击耐受性会下降，CF/PPS 层压板的性能保持率通常较低。然而，本研究提出的热修复工艺可显著提高 CF/PPS 层压材料的性能。此外，CF/PPS 层压板的性能修复程度始终高于 CF/PEEK 层压板，这与 PEEK 树脂的半结晶性质密切相关。

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引用次数: 0

Statistical characteristics of realistic fiber misalignments of unidirectional composites: Fitting distributions and scanning length effects 单向复合材料现实纤维错位的统计特征：拟合分布和扫描长度效应

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-01 DOI: 10.1016/j.tws.2024.112621

Tao Zheng , Fenghao Jia , Zhongyu Wang , Zhanguang Chen , Fengnan Guo , Licheng Guo

This paper presents a comprehensive study on the statistical characteristics of angle, tortuosity, curvature and wave magnitude to deepen the understanding of realistic fiber misalignments within unidirectional composites. A feasible fiber path reconstruction procedure has been optimized, which can be applicable to other types of composites. The high-resolution micrographs are acquired through X-ray computed tomography. The individual fiber segmentation is implemented using a U-Net deep learning method, and the fiber trajectories are reconstructed with the aid of a tracing algorithm. The stepped fiber trajectories are slightly smoothed and a polynomial fitting formula is adopted to quantitatively describe the fiber paths. The statistical characteristics corresponding to the differential tortuosity, misalignment angle, spatial curvature and wave magnitudes are comprehensively analyzed, with emphasis on their fitting distributions and scanning length effects. The collected data indicate that the statistical distributions of differential tortuosity and angle, curvature, and wave magnitude can be well fitted by normal, lognormal and Weibull equations, respectively. Particularly, the differential tortuosity and wave magnitude are overall features of individual fiber trajectory, which are highly correlated with the scanning length. In contrast, the angle and curvature are local features, so a smaller scanning length could obtain convergent results.

本文对角度、迂回度、曲率和波幅的统计特征进行了全面研究，以加深对单向复合材料中现实纤维错位的理解。研究优化了可行的纤维路径重建程序，该程序可适用于其他类型的复合材料。高分辨率显微照片是通过 X 射线计算机断层扫描获得的。使用 U-Net 深度学习方法对单根纤维进行分割，并借助追踪算法重建纤维轨迹。对阶梯状纤维轨迹进行轻微平滑处理，并采用多项式拟合公式对纤维路径进行定量描述。对迂回差、错位角、空间曲率和波幅对应的统计特征进行了综合分析，重点分析了它们的拟合分布和扫描长度效应。采集的数据表明，微分迂回度和角度、曲率和波幅的统计分布分别可以很好地用正态、对数正态和威布尔方程拟合。特别是，微差迂曲度和波幅是单个纤维轨迹的整体特征，与扫描长度高度相关。相比之下，角度和曲率是局部特征，因此较小的扫描长度也能得到趋同的结果。

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引用次数: 0

Mechanical performance analysis method for ribbed H-section aluminum alloy members with initial curvature and torsion angle 具有初始曲率和扭转角的带肋 H 型截面铝合金构件的机械性能分析方法

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-11-01 DOI: 10.1016/j.tws.2024.112662

Guojun Sun , Bo Li , Jinzhi Wu

In this study, an experimental investigation was conducted on the axial compression performance of ribbed H-section aluminum alloy members with initial curvature and torsion angle under varying boundary conditions, including one end hinged with the other rigidly connected, and both ends rigidly connected. Ultimate bearing capacity and failure modes were identified under real loads and subsequently compared with previous findings from our research group on members with hinged ends. To account for initial imperfections introduced during processing and transportation, 3D scanning technology was utilized to capture the precise geometrical dimensions, constructing an accurate numerical simulation model. The experimental results were corroborated with numerical simulations, leading to the proposal of an analytical method for members with initial curvature and torsion angle. Furthermore, extensive parametric analysis elucidated the impact of initial curvature, torsion angle, and slenderness ratio on the ultimate bearing capacity, culminating in the formulation of the stability factor and calculated length factor based on numerical outcomes. The study discovered significant variances in bearing capacity under different boundary conditions, with one-end hinged and one-section rigidly connected, and two-end rigidly connected conditions exhibiting 1.4 and 2.1 times the capacity of the hinged-at-both-ends scenario. Under different boundary conditions, the axial compression members were subjected to flexural-torsional buckling failure. Moreover, when the ultimate bearing capacity was reached, the lower flange of the member and the web near the lower flange appeared obvious buckling phenomenon. The numerical analysis aligned well with experimental data, validating the simulation method's reliability and revealing the stress distribution and evolution during member failure. These findings offer vital theoretical insights and technical support for engineering design and practical applications.

本研究对具有初始曲率和扭转角的带肋 H 型铝合金构件在不同边界条件下的轴向压缩性能进行了实验研究，这些边界条件包括一端铰接、另一端刚性连接以及两端刚性连接。研究确定了实际载荷下的极限承载能力和失效模式，并将其与我们研究小组之前对铰接端构件的研究结果进行了比较。为了考虑到加工和运输过程中产生的初始缺陷，利用三维扫描技术捕捉了精确的几何尺寸，构建了精确的数值模拟模型。实验结果与数值模拟结果相互印证，从而为具有初始曲率和扭转角的构件提出了一种分析方法。此外，广泛的参数分析阐明了初始曲率、扭转角和细长比对极限承载力的影响，最终根据数值结果制定了稳定系数和计算长度系数。研究发现，在不同的边界条件下，承载能力存在显著差异，单端铰接和单节刚性连接以及双端刚性连接条件下的承载能力分别是两端铰接情况下的 1.4 倍和 2.1 倍。在不同的边界条件下，轴向受压构件发生了挠曲扭转屈曲破坏。此外，当达到极限承载力时，构件的下翼缘和靠近下翼缘的腹板出现了明显的屈曲现象。数值分析与实验数据吻合良好，验证了模拟方法的可靠性，并揭示了构件失效时的应力分布和演变过程。这些发现为工程设计和实际应用提供了重要的理论启示和技术支持。

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引用次数: 0

Shear elastic buckling of corrugated steel plate shear walls with stiffeners considering torsional rigidity 考虑扭转刚度的带加强筋波纹钢板剪力墙的剪切弹性屈曲

IF 5.7 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2024-10-31 DOI: 10.1016/j.tws.2024.112646

Ruo-Min Wu, Chao-Qun Yu, Ling-Qi Wang, Jing-Zhong Tong

This paper conducted theoretical and numerical investigations on shear elastic buckling formulas of stiffened corrugated steel plate shear walls (SCSPSWs) considering torsional rigidities of stiffeners. Firstly, based on the orthotropic plate theory and the energy method, a theoretical model for the derivation of elastic buckling coefficients was established, introducing the torsional strain energy term of the stiffeners. On this basis, the variation law of the elastic buckling coefficient of the walls concerning the stiffener positions was studied, determining the optimal layout of the stiffeners. The formula for calculating the elastic buckling coefficient at any stiffener layout was provided. Furthermore, based on the stiffeners arranged in the optimal layout, the transition torsional rigidity of the stiffeners was determined, and the formulas for the elastic buckling coefficient of the SCSPSW with stiffeners considering torsional rigidity were proposed, in which the enhancement of torsional constraints provided by the stiffeners was measured by an enhancement factor. Finally, eigenvalue buckling analyses were performed based on finite element models to validate the theoretical analysis results on the optimal stiffener layout and elastic buckling coefficient.

本文对考虑加劲件扭转刚度的加劲波纹钢板剪力墙（SCSPSWs）的剪切弹性屈曲公式进行了理论和数值研究。首先，基于各向同性板理论和能量法，建立了推导弹性屈曲系数的理论模型，引入了加劲件的扭转应变能项。在此基础上，研究了墙体弹性屈曲系数随加劲件位置的变化规律，确定了加劲件的最佳布局。提供了在任何加强筋布局下的弹性屈曲系数计算公式。此外，根据加劲件的最佳布局，确定了加劲件的过渡扭转刚度，并提出了考虑扭转刚度的带加劲件 SCSPSW 的弹性屈曲系数公式，其中加劲件提供的扭转约束的增强用增强系数来衡量。最后，基于有限元模型进行了特征值屈曲分析，以验证关于最佳加劲件布局和弹性屈曲系数的理论分析结果。

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引用次数: 0