Thin-Walled Structures最新文献_第4页

Quasi-static and dynamic compression behavior of 3D-printed TPMS–Gyroid cellular material 3d打印TPMS-Gyroid细胞材料的准静态和动态压缩行为

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-02-16 DOI: 10.1016/j.tws.2026.114681

Wenfang Yuan , Kefeng Peng , Yuying Ma , Yuxuan Zheng , Baixue Chang , Zhijun Zheng

TPMS–Gyroid cellular materials demonstrate excellent performance in terms of specific strength and energy absorption, making them ideal candidate materials for lightweight protective structure design. The mechanical response of Gyroid cellular material under quasi-static compression, direct impact, and mass impact was experimentally investigated in this study. Constitutive models were employed to characterize the mechanical response and power-law relationships between their material parameters and the relative density were obtained. Cellular specimens were fabricated from PLA and tested by using the Taylor–Hopkinson pressure bar experimental technique combined with high-speed photography. In experimental tests, two deformation patterns were observed: a topology-dominated, random, layered collapse under quasi-static loading and an inertia-dominated, layer-by-layer collapse under dynamic impact. The initial crush stress and strain-hardening parameter, and their power-law density dependence, were determined. Experimental tests involving both large-mass, low-velocity and small-mass, high-velocity impacts confirmed that the dynamic constitutive model of Gyroid cellular material demonstrated excellent predictive performance. Therefore, the feasibility and reliability of the constitutive relationship for Gyroid cellular materials were verified, and the resulting shock models can guide the design of protective structures in engineering practice.

TPMS-Gyroid细胞材料在比强度和能量吸收方面表现出优异的性能，使其成为轻量化防护结构设计的理想候选材料。实验研究了Gyroid细胞材料在准静态压缩、直接冲击和质量冲击下的力学响应。采用本构模型表征其力学响应，得到了材料参数与相对密度之间的幂律关系。采用聚乳酸制备细胞标本，采用Taylor-Hopkinson压杆实验技术结合高速摄影技术进行实验。在实验测试中，观察到两种变形模式：准静态载荷下拓扑主导的随机分层坍塌和动态冲击下惯性主导的逐层坍塌。确定了初始破碎应力和应变硬化参数及其与密度的幂律关系。大质量低速撞击和小质量高速撞击的实验测试证实，Gyroid细胞材料的动态本构模型具有良好的预测性能。从而验证了Gyroid蜂窝材料本构关系的可行性和可靠性，所建立的冲击模型可以指导工程实践中防护结构的设计。

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引用次数: 0

Buckling behaviour of high-strength concrete-filled high-strength steel tubular columns after fire exposure 高强钢管混凝土柱火灾后的屈曲行为

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-02-07 DOI: 10.1016/j.tws.2026.114640

Tao Du , Faqi Liu , Hua Yang , Yinglong Li

The emphasis of this paper is on the buckling behaviour of high-strength concrete-filled high-strength steel tubular (HCFHST) columns after exposure to fire. Nine slender HCFHST specimens were subjected to ISO 834 standard fire and axial load after cooling. The failure mode, deformation, buckling capacity, and strain of the specimens were monitored and reported. With a reduction close to that in cross-sectional capacity, the buckling capacity of specimens with a slenderness ratio of 53 decreases by 32.6% and 48.1% following exposure to fire for 45 min and 90 min, respectively. Furthermore, the experimental results indicate that the effects of fire duration and slenderness ratio on buckling capacity were essentially found to be uncoupled within the experimental parameters. A thermo-mechanical coupled finite element model was established using ABAQUS and confirmed to be reliable through comparison with the test results. A parametric analysis was carried out to investigate the effects of a wider range of parameters, including fire duration, cross-sectional diameter, slenderness ratio, steel ratio, and material strength, on the residual buckling resistance. Finally, the historical peak temperatures and the reduction in material residual performance were incorporated into the existing ambient-temperature resistance design methods. The methods can be used to predict the residual buckling resistance of slender HCFHST columns, assess their post-fire safety, and provide a basis for subsequent strengthening.

本文重点研究了高强钢管混凝土柱在火灾作用下的屈曲行为。9个细长的HCFHST试件在冷却后经受ISO 834标准的火灾和轴向荷载。监测并报告了试件的破坏模式、变形、屈曲能力和应变。长细比为53的试件在火灾作用45 min和90 min后，其屈曲能力分别下降了32.6%和48.1%，与截面容量下降幅度相近。此外，实验结果表明，在实验参数范围内，燃烧时间和长细比对屈曲能力的影响基本上是不耦合的。利用ABAQUS建立了热-力耦合有限元模型，并与试验结果进行了对比，验证了模型的可靠性。通过参数分析，研究了火灾持续时间、截面直径、长细比、钢比和材料强度等参数对残余抗屈曲性能的影响。最后，将历史峰值温度和材料残留性能的降低纳入现有的耐环境温度设计方法。该方法可用于预测细长HCFHST柱的残余抗屈曲能力，评估其火灾后安全性，为后续加固提供依据。

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引用次数: 0

A low-cycle fatigue crack growth prediction method for ship stiffened plates considering accumulative plastic damage 考虑累积塑性损伤的船舶加筋板低周疲劳裂纹扩展预测方法

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-02-11 DOI: 10.1016/j.tws.2026.114658

Yuelin Song , Zhi Xu , Chenyang Liu , Ziya Peng , Shanyu Xu , Cheng Zhao , Jiping Zhang

This research explores the characteristics of low-cycle fatigue crack growth in stiffened plate structures from the perspective of cumulative plastic damage. A novel predictive approach for fatigue crack growth rates is proposed, which integrates a correction factor to account for welding residual stress effects and utilizes accumulated plastic dissipation energy at a critical distance ahead of the crack tip as the driving parameter. The stiffened plate specimen with a central stiffener is fabricated to examine crack propagation behavior, focusing on single-sided and double-sided crack positions relative to the stiffener. A numerical program is developed to simulate simultaneous crack propagation in the plate and stiffener, enabling evaluation of cumulative plastic damage under cyclic stress. The proposed method demonstrates high accuracy in predicting fatigue crack growth rates for welded stiffened plates, as evidenced by strong agreement between predictions and experimental data.

本研究从累积塑性损伤的角度探讨加筋板结构的低周疲劳裂纹扩展特征。提出了一种新的疲劳裂纹扩展速率预测方法，该方法综合考虑了焊接残余应力效应的修正系数，并利用裂纹尖端前方临界距离处累积的塑性耗散能作为驱动参数。本文制作了带加劲肋的加筋板试件，主要研究了与加劲肋相对的单面和双面裂纹的扩展行为。开发了一个数值程序来模拟板和加劲板的同时裂纹扩展，从而能够评估循环应力下的累积塑性损伤。该方法对焊接加筋板疲劳裂纹扩展速率的预测具有较高的准确性，预测结果与实验数据吻合较好。

引用次数: 0

Identification of the aerodynamic coefficients and forces of vortex-induced vibration of bridge decks based on the particle filter algorithm 基于粒子滤波算法的桥面涡激振动气动系数和动力识别

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-02-21 DOI: 10.1016/j.tws.2026.114698

Dandan Xia, Wanghua Yu, Ziyong Lin, Li Lin

Aerodynamic forces and coefficients are essential for explaining the mechanism and suppression of the vortex-induced vibrations (VIVs) of bridge decks in large-span bridges. However, in a wind-tunnel test, the aerodynamic force usually cannot be directly measured. In this research, a modified particle filter with unknown inputs that combines a particle filter algorithm and a Kalman filter (PKF-UI) is proposed to identify the aerodynamic coefficients and forces of VIVs. The effectiveness of the proposed PKF-UI method is firstly verified using three-degree-of-freedom nonlinear structures. The effects of the number of particles and noise level are discussed. The results show that the proposed method can effectively identify both structural parameters and unknown inputs. With the addition of 10 % white noise for the measurement, the identified structural parameter errors are 10 %, indicating that such a method can be applied effectively to the experimental data. Wind-tunnel tests are conducted on the bridge deck of a large-span bridge, and VIVs are obtained. With the utilization of the proposed method, the accelerations and displacements, which can be measured in the experiment, are fused to identify the aerodynamic forces and coefficients in the VIV lock-in regions.

气动力和气动力系数对于解释大跨度桥梁桥面涡激振动的机理和抑制是至关重要的。然而，在风洞试验中，通常无法直接测量空气动力。本文提出了一种结合粒子滤波算法和卡尔曼滤波（PKF-UI）的未知输入改进粒子滤波算法，用于识别涡动飞行器的气动系数和动力。首先用三自由度非线性结构验证了所提出的PKF-UI方法的有效性。讨论了粒子数和噪声水平的影响。结果表明，该方法能有效识别结构参数和未知输入。在测量中加入10%的白噪声后，识别出的结构参数误差为10%，表明该方法可以有效地应用于实验数据。对某大跨度桥梁的桥面进行了风洞试验，获得了涡激振动。利用所提出的方法，将实验中可以测量到的加速度和位移进行融合，以识别涡激飞行器锁定区的气动力和系数。

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引用次数: 0

Isogeometric solid-shell framework for nonlinear buckling analysis of variable-stiffness composite cylindrical shells incorporating measured imperfections and thickness variations 考虑测量缺陷和厚度变化的变刚度复合圆柱壳的非线性屈曲分析等几何实体-壳框架

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-02-27 DOI: 10.1016/j.tws.2026.114736

Hao Miao, Peng Jiao, Baoxin Nie, Zhihuan Ding, Zhiping Chen

Thin-walled composite cylindrical shells hold significant importance in aerospace applications. The utilization of variable-stiffness composites (VSC) with curvilinear fibers is gaining increasing attention for buckling design of cylindrical shells. Given their substantially greater complexity in both fiber orientation distribution and thickness variation compared to conventional straight-fiber composites, nonlinear buckling analysis of VSC structure via the finite element method incurs considerably higher computational demands. To enhance the computational efficiency, an IGA-based framework aiming at buckling prediction of VSC cylindrical shells with non-uniform thickness is established in this paper for the first time. To address the practical limitations of existing IGA surface reconstruction methods, we propose a novel cylindrical shell modeling approach that integrates NURBS surface fitting with the Inverse Distance Weighting (IDW) method, enabling effective reconstruction of VSC cylindrical shells. Isogeometric shell elements based on 7-parameter solid shell theory incorporating artificial damping are used for nonlinear buckling analysis of VSC shell structures. Four representative case studies validate the accuracy and computational efficiency of the proposed element and framework. Results demonstrate that the IGA elements consistently achieve significantly higher computational efficiency than conventional shell elements. The proposed framework offers a novel approach for the application of IGA in nonlinear buckling analysis of composite structures.

薄壁复合材料圆柱壳在航空航天应用中具有重要意义。曲线纤维变刚度复合材料在圆柱壳屈曲设计中的应用越来越受到重视。与传统的直纤维复合材料相比，VSC结构在纤维取向分布和厚度变化方面具有更大的复杂性，因此通过有限元方法对VSC结构进行非线性屈曲分析需要相当高的计算量。为了提高计算效率，本文首次建立了一种基于iga的非均匀厚度VSC圆柱壳屈曲预测框架。为了解决现有IGA曲面重建方法的实际局限性，提出了一种将NURBS曲面拟合与逆距离加权（IDW）方法相结合的新型圆柱壳建模方法，实现了VSC圆柱壳的有效重建。采用基于七参数实体壳理论并结合人工阻尼的等几何壳单元对VSC壳结构进行了非线性屈曲分析。四个典型的案例研究验证了所提出的元素和框架的准确性和计算效率。结果表明，IGA单元的计算效率明显高于常规壳单元。该框架为IGA在复合材料结构非线性屈曲分析中的应用提供了一种新的方法。

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引用次数: 0

Intelligent vibration control of variable stiffness bistable composites laminate for curvilinear fiber trajectory with asymmetric laying strategy 基于非对称铺放策略的变刚度双稳态复合材料曲线轨迹层合板振动智能控制

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-02-17 DOI: 10.1016/j.tws.2026.114677

X.M. Liu , Y.X. Hao , W. Zhang , H.D. Xia , S.W. Yang , Y.T. Cao

Recently, variable-stiffness bistable laminates with curved fibers have gained attention in deformation structure research. Compared to straight-fiber bistable laminates, they offer reduced weight, adjustable stiffness, and a broader range of stable configurations. This study explores the stable-state configuration, natural frequency, and nonlinear vibration-active control using active methods for a bistable composite laminate with variable stiffness (VSBCL) simply supported at its four corners. Using a 17-parameter polynomial configuration function that accounts for the local influence and boundary effects of smart piezoelectric materials on the stable-state configuration of bistable structures, the configuration equation for the system is formulated using the von Karman geometric nonlinear strain-displacement relation and the energy principle. Furthermore, a nonlinear ordinary differential equation incorporating electromechanical coupling is derived for the system. Using this equation, the characteristics of the stable-state configuration under various fiber curvature-laying paths are examined and compared with finite-element analysis results. The natural vibration characteristics are then discussed. Employing fuzzy control theory, a fuzzy controller with VSCBL curvature as the key parameter is designed. Its performance and reliability are further validated through a comparative analysis with the traditional PID controller. Then, the nonlinear dynamic behavior and fuzzy control of the bistable laminated structure are investigated under various loading conditions, including step, decreasing, increasing, and sinusoidal loads. Numerical simulations under multiple conditions show that the proposed fuzzy control strategy greatly improves structural response regulation, providing a practical method for actively controlling a vibrating variable-stiffness bistable composite laminate.

近年来，弯曲纤维变刚度双稳态层合板在变形结构研究中得到了广泛的关注。与直纤维双稳态层压板相比，它们提供了更轻的重量，可调节的刚度和更广泛的稳定配置。本研究探讨了四角简支变刚度（VSBCL）双稳态复合材料层板的稳态结构、固有频率和非线性振动主动控制。采用考虑智能压电材料对双稳结构稳态组态的局部影响和边界效应的17参数多项式组态函数，利用von Karman几何非线性应变-位移关系和能量原理建立了系统的组态方程。在此基础上，推导了考虑机电耦合的非线性常微分方程。利用该方程，考察了不同光纤曲率铺设路径下的稳态结构特性，并与有限元分析结果进行了比较。然后讨论了其固有振动特性。利用模糊控制理论，设计了以VSCBL曲率为关键参数的模糊控制器。通过与传统PID控制器的对比分析，进一步验证了其性能和可靠性。然后，研究了双稳层合结构在阶跃载荷、递减载荷、递增载荷和正弦载荷下的非线性动力行为和模糊控制。多种工况下的数值仿真结果表明，所提出的模糊控制策略大大改善了结构的响应调节，为变刚度双稳态复合材料层合板的振动主动控制提供了一种实用的方法。

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引用次数: 0

Effects of processing parameters on the Mode I interlaminar fracture toughness of additively manufactured continuous glass fiber reinforced PEEK composites 工艺参数对增材制造连续玻纤增强PEEK复合材料I型层间断裂韧性的影响

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-02-24 DOI: 10.1016/j.tws.2026.114671

Hao Zhang , Yiwei Chen , Wenzhe Song , Jing-Hua Zheng , Congze Fan , Zhongde Shan

Additive manufacturing of continuous fiber reinforced polymer composites enables precise fiber placement and design flexibility, making it a key technology for fabricating aerospace and automotive components. Evaluating the interlaminar fracture toughness of additively manufactured composites is crucial, as low resistance to opening-mode delamination can compromise interlayer fusion quality and impair the reliability of high-precision applications. This study employed Response Surface Methodology (RSM) to correlate nozzle temperature, printing speed, and layer thickness with the Mode I interlaminar fracture toughness (G_IC) of additively manufactured CGF/PEEK composites through Double Cantilever Beam (DCB) tests. Analysis of Variance (ANOVA) and univariate analysis were employed to evaluate the effects of individual factors and their interactions, revealing statistically significant influences on fracture toughness. Results showed that layer thickness had the most significant effect on G_IC. Reducing the layer thickness from 0.24 mm to 0.16 mm increased the average G_IC from 57.2 J/m² to 533.2 J/m². Mechanistically, thinner layers facilitated deeper thermal penetration and polymer chain entanglement while suppressing interlaminar voids. These conditions facilitated robust energy-dissipation mechanisms, including fiber bridging and microscale tearing, during the fracture process. To further elucidate the interlaminar behavior of CGF/PEEK, the fusion process and failure characteristics were analyzed, leading to the development of a mechanistic model that demonstrates high predictive accuracy (R²≈0.972). This study establishes a processing foundation for producing additively manufactured CGF/PEEK components with high interlaminar fracture toughness suitable for aerospace applications.

连续纤维增强聚合物复合材料的增材制造能够实现精确的纤维放置和设计灵活性，使其成为制造航空航天和汽车部件的关键技术。评估增材制造复合材料的层间断裂韧性是至关重要的，因为低的抗开模脱层能力会影响层间融合质量，影响高精度应用的可靠性。本研究采用响应面法（RSM）通过双悬臂梁（DCB）测试，将喷嘴温度、打印速度和层厚与增材制造的CGF/PEEK复合材料的I型层间断裂韧性（GIC）联系起来。采用方差分析（ANOVA）和单变量分析来评估个体因素及其相互作用的影响，结果显示对断裂韧性的影响具有统计学意义。结果表明，层厚对GIC的影响最为显著。将层厚度从0.24 mm减少到0.16 mm，平均GIC从57.2 J/m2增加到533.2 J/m2。从机理上讲，更薄的层有助于更深的热渗透和聚合物链纠缠，同时抑制层间空隙。在断裂过程中，这些条件促进了强大的能量耗散机制，包括纤维桥接和微尺度撕裂。为了进一步阐明CGF/PEEK的层间行为，分析了CGF/PEEK的熔合过程和失效特征，建立了具有较高预测精度（R2≈0.972）的机理模型。本研究为增材制造适用于航空航天的具有高层间断裂韧性的CGF/PEEK组件奠定了工艺基础。

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引用次数: 0

Designing anisotropic mechanical metamaterials and metastructures: a review 各向异性力学超材料与超结构设计综述

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-02-24 DOI: 10.1016/j.tws.2026.114719

Zhongkai Ji , Dawei Li , Xiaoya Zhai , Jie Gao , Yunlong Tang , Ning Dai , Wenhe Liao , Yong Zhao , Yi Min Xie

Mechanical metamaterials and metastructures exhibit unconventional mechanical and functional properties not found in conventional materials. The unique characteristics originate from special geometric and topological arrangements of their constituent unit cells. Anisotropy is a fundamental physical property and is instrumental in tailoring mechanical responses. Its strategic implementation is a key determinant for achieving structure-function integration, expanding the accessible design space, and addressing multi-physics coupling requirements. Consequently, the precise orchestration of material architecture to elicit targeted functionalities has become a central theme in advanced materials research. Advanced computational design and additive manufacturing are pivotal in creating bio-inspired metamaterials, mimicking the complex anisotropy of natural structures to achieve integrated functionalities. This review summarizes recent advancements in anisotropic design, covering its conceptual evolution and classification. It analyzes unit-cell design methodologies, highlighting the shift toward intelligent, data-driven algorithms. The review explores macroscopic deformation in metastructures, controlled by spatially modulating unit-cell properties. Finally, this work synthesizes key strategies and evaluates future trajectories, aiming to establish a theoretical foundation and propose new paradigms. These efforts are intended to accelerate the discovery and implementation of next-generation metamaterials and metastructures.

机械超材料和超结构表现出传统材料所没有的非常规机械和功能特性。其独特的特性源于其组成单元细胞的特殊几何和拓扑排列。各向异性是一种基本的物理性质，在调整力学响应方面起着重要作用。其战略实施是实现结构-功能集成、扩展可访问设计空间和解决多物理场耦合需求的关键决定因素。因此，材料结构的精确编排以引出目标功能已成为先进材料研究的中心主题。先进的计算设计和增材制造是创造仿生超材料的关键，模仿自然结构的复杂各向异性，以实现集成功能。本文综述了各向异性设计的最新进展，包括各向异性设计的概念演变和分类。它分析了单元格设计方法，强调了向智能、数据驱动算法的转变。这篇综述探讨了元结构中的宏观变形，由空间调节的单元胞性质控制。最后，本文综合了关键策略并评估了未来的发展轨迹，旨在建立理论基础并提出新的范式。这些努力旨在加速下一代超材料和超结构的发现和实现。

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引用次数: 0

Folding mechanism within a prestrained composite tape-spring structure 预紧复合带簧结构内的折叠机构

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-02-26 DOI: 10.1016/j.tws.2026.114715

Chenmin Zhao , Bing Wang , Chenglong Guan , Guofu Lian

A composite tape-spring (CTS) structure is a thin-walled structure with a curved cross-section. Owing to its curved cross-section being capable of flattening, the CTS is well-suited for folding. Its ability to fold under large displacement makes it attractive as a hinge safety component. Compared with the traditional lock-link connection, its weight, complexity and maintenance can be reduced. Among them, the internal stress level of the CTS determines its folding mechanism, while the traditional composite manufacturing method is tricky to tailor the internal stress. In this paper, we developed a biaxial elastic fibre prestraining method to design prestrained CTS. The biaxial fibre tensile rig was designed to apply tension in the warp and weft directions of the plain-weave carbon prepreg, and the tension constant during the curing process. The FEA and theoretical were established and calibrated by the experimental data. The peak strain of the folding band was studied to evaluate the effect of prestrain on the folding strain. It is found that elastic fibre prestraining can effectively adjust the internal strain/stress level of the prestrained CTS, and can reduce the maximum tensile strain, thereby improving the load-carrying capacity. These findings will contribute to the structural design of foldable mechanical hinges.

复合带弹簧（CTS）结构是一种具有弯曲截面的薄壁结构。由于其弯曲的横截面能够变平，CTS非常适合折叠。其在大位移下的折叠能力使其作为铰链安全组件具有吸引力。与传统的锁扣连接相比，它的重量、复杂性和维护都大大降低。其中，CTS的内应力水平决定了其折叠机理，而传统的复合材料制造方法难以定制内应力。本文提出了一种双轴弹性纤维预紧法来设计预紧CTS。设计了双轴拉伸装置，对平纹碳预浸料的经纬方向施加张力，并测定了固化过程中的张力常数。建立了有限元分析和理论分析，并用实验数据进行了校核。研究了折叠带的峰值应变，评价了预应变对折叠应变的影响。研究发现，弹性纤维预紧可以有效调节预紧CTS的内部应变/应力水平，降低最大拉伸应变，从而提高承载能力。这些发现将有助于可折叠机械铰链的结构设计。

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引用次数: 0

An analytical solution for elliptical arc crack in orthotropic materials with equal characteristic roots 等特征根正交各向异性材料椭圆弧裂纹的解析解

IF 6.6 1区工程技术 Q1 ENGINEERING, CIVIL

Thin-Walled Structures

Pub Date : 2026-05-01 Epub Date: 2026-01-26 DOI: 10.1016/j.tws.2026.114583

Wei Yi, Yinian Wu, Shuxin Huang, Qiuhua Rao, Jiawei Liu, Kai Shen, Shaobo Jin

Accurate determination of stress intensity factors (SIFs) for a curved crack in orthotropic materials is critically important for assessing the stability of engineering structures and predicting the formation of fracture networks in shale-gas and geothermal development. Although the semi-analytical solutions for curved crack in anisotropic materials are well-established, fully analytical solutions for elliptical arc cracks in orthotropic materials remain scarce. In this study, we develop a closed-form analytical solution for the SIFs of an elliptical arc crack embedded in an orthotropic infinite plane under remote loading, under the condition that the material exhibits equal characteristic roots. The proposed method integrates affine transformation, conformal mapping, and complex variable theory to transform the original orthotropic problem into an equivalent isotropic one, whereby explicit expressions for the complex potentials and SIFs are systematically derived. The accuracy and robustness of the solution are validated through comparison with existing exact results for circular arc crack and finite element results for elliptical arc crack. Furthermore, the presented analytical framework can be extended to analyze other types of crack configurations such as branched cracks in orthotropic materials with equal characteristic roots, providing a theoretical foundation for advanced fracture mechanics assessments in anisotropic solids.

准确确定正交异性材料弯曲裂缝的应力强度因子（SIFs）对于评估工程结构的稳定性以及预测页岩气和地热开发中裂缝网的形成至关重要。虽然各向异性材料中弯曲裂纹的半解析解已经建立，但正交各向异性材料中椭圆弧裂纹的完全解析解仍然很少。在本研究中，我们开发了在材料具有相等特征根的条件下，嵌入正交各向异性无限平面的椭圆弧裂纹在远程加载下的SIFs的封闭形式解析解。该方法结合仿射变换、保角映射和复变量理论，将原正交各向异性问题转化为等效的各向同性问题，系统地推导了复势和SIFs的显式表达式。通过与已有的圆弧裂纹精确解和椭圆弧裂纹有限元解的比较，验证了该解的准确性和鲁棒性。此外，所提出的分析框架可以推广到其他类型的裂纹形态，如具有等特征根的正交各向异性材料中的分支裂纹，为各向异性固体的高级断裂力学评估提供理论基础。

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引用次数: 0