【新文速递】2024年11月20日固体力学SCI期刊最新文章

今日更新：International Journal of Solids and Structures 3 篇，Journal of the Mechanics and Physics of Solids 4 篇，International Journal of Plasticity 1 篇，Thin-Walled Structures 6 篇International Journal of Solids and StructuresAnalyzing creep-recovery behavior of tropical Entandrophragma cylindricum wood: Traditional and fractional modeling methodsL.C. Nguedjio, J.S. Mabekou Takam, R. Moutou Pitti, B. Blaysat, N. Sauvat, J. Gril, F. Zemtchou, P.K. Talladoi:10.1016/j.ijsolstr.2024.113122热带毛竹木材蠕变恢复行为分析：传统与分数模型方法Nowadays, wood stands as one of the foremost used construction materials, owing largely to its exceptional physical and mechanical properties. Ensuring the safety of timber structures necessitates thorough investigations into the influential phenomena that significantly affect their strength and longevity. The aim of this paper is to study the coupled creep-recovery behavior of tropical wood from the Entandrophragma cylindricum species by evaluating the influence of stress levels on the performance of rheological models. Hence, the Burger and Weibull classic models were introduced to elucidate these phenomena. These models have been compared with the fractional Maxwell and Zener models. Following the simulations, the Burger classic model effectively characterized creep and recovery, comprising elastic, viscoelastic, and viscous elements arranged in series, as well as the classic Weibull model. During the recovery phase, the four-parameter Weibull model demonstrated a satisfying description, achieving 99% accuracy compared to 97% for the four-parameter Burger classic model. Three-parameter fractional Maxwell model fit all phases of the process for all deformations with an average accuracy of 98% for creep and 95% for recovery. These results provide valuable information on the material’s ability to recover from deformation and offer essential insights for materials characterization, engineering design, and quality assurance processes in materials engineering.如今，木材作为最常用的建筑材料之一，主要是由于其特殊的物理和机械性能。为了确保木结构的安全，必须对影响其强度和寿命的重要现象进行深入调查。本文的目的是通过评估应力水平对流变模型性能的影响，研究热带白茅栎（Entandrophragma um）种木材的蠕变-恢复耦合行为。因此，引入了Burger和Weibull经典模型来解释这些现象。这些模型与分数麦克斯韦模型和齐纳模型进行了比较。在模拟之后，Burger经典模型有效地表征了蠕变和恢复，包括弹性、粘弹性和粘性单元的串联，以及经典Weibull模型。在恢复阶段，四参数威布尔模型表现出令人满意的描述，达到99%的准确率，而四参数汉堡经典模型的准确率为97%。三参数分数阶Maxwell模型拟合所有变形过程的所有阶段，蠕变的平均精度为98%，恢复的平均精度为95%。这些结果为材料从变形中恢复的能力提供了有价值的信息，并为材料工程中的材料表征、工程设计和质量保证过程提供了重要的见解。Free vibration of electroelastic thin-walled structures under static loadA.O. Kamenskikh, S.V. Lekomtsev, A.N. Senin, V.P. Matveenkodoi:10.1016/j.ijsolstr.2024.113123静载作用下电弹性薄壁结构的自由振动The mathematical formulation and finite element algorithm for solving the problem of free vibration of electroelastic plates and shells under static load are considered. In modeling, the curvilinear surface of a thin-walled structure is represented as a set of flat segments. In each of them, the physical relations of the classical laminated plate theory and the theory of electroelasticity, written for a plane stress state, are fulfilled. The strains are determined using nonlinear equations, which are linearized with respect to the state with a small deviation from the initial equilibrium position caused by static forces. As an examples, we consider a rectangular plate and a circular cylindrical shell with a piezoelectric element under the action of the uniform pressure. The validity of the solution is confirmed by comparing the normal displacement and natural frequencies of vibration with experimental data and results obtained with the use of commercial finite element software.考虑了求解静载荷作用下电弹性板壳自由振动问题的数学表达式和有限元算法。在建模中，薄壁结构的曲线表面被表示为一组平面段。在每一种情况下，都满足了经典层合板理论和电弹性理论在平面应力状态下的物理关系。应变是用非线性方程来确定的，这些方程与静力引起的与初始平衡位置的小偏差的状态线性化。作为一个例子，我们考虑在均匀压力作用下的矩形板和带有压电元件的圆柱壳。通过将法向位移和振动固有频率与实验数据以及利用商业有限元软件得到的结果进行比较，证实了该解的有效性。Advanced finite element modeling methods for tensile and bending analysis of arresting gear cablesLong Li, Yiming Peng, Yifeng Wang, Xiaohui Wei, Hong Niedoi:10.1016/j.ijsolstr.2024.113126拦阻齿轮索拉伸和弯曲分析的先进有限元建模方法This study addresses the gap in understanding the dynamic bending behavior of multi-layer twisted steel cable, pivotal in various industrial applications such as naval aircraft arresting systems. Utilizing advanced finite element modeling, the research explores the mechanical responses of these cables under macroscopic bending scenarios. By integrating beam elements and connectors within the finite element framework, the study simulates complex inter-strand interactions under various loading conditions. Results indicate that this method significantly enhances the prediction accuracy of the cables’ mechanical properties, thus offering substantial improvements in design and performance analysis of arresting gear systems. This study’s value lies in its potential to refine mechanical modeling of complex cable systems, thereby optimizing operational efficiency and safety in engineering applications.这项研究解决了理解多层扭曲钢丝绳动态弯曲行为的空白，在各种工业应用中至关重要，如海军飞机拦阻系统。利用先进的有限元模型，研究了这些电缆在宏观弯曲情况下的力学响应。通过在有限元框架内集成梁单元和连接件，该研究模拟了各种载荷条件下复杂的链间相互作用。结果表明，该方法显著提高了索的力学性能预测精度，从而为拦阻齿轮系统的设计和性能分析提供了实质性的改进。这项研究的价值在于它有可能完善复杂电缆系统的力学建模，从而优化工程应用中的操作效率和安全性。Journal of the Mechanics and Physics of SolidsEffective extensional-torsional elasticity and dynamics of helical filaments under distributed loadsMichael Gomez, Eric Laugadoi:10.1016/j.jmps.2024.105921分布荷载作用下螺旋细丝的有效伸扭弹性与动力学We study slender, helical elastic rods subject to distributed forces and moments. Focussing on the case when the helix axis remains straight, we employ the method of multiple scales to systematically derive an ‘equivalent-rod’ theory from the Kirchhoff rod equations: the helical filament is described as a naturally-straight rod (aligned with the helix axis) for which the extensional and torsional deformations are coupled. Importantly, our analysis is asymptotically exact in the limit of a ‘highly-coiled’ filament (i.e., when the helical wavelength is much smaller than the characteristic lengthscale over which the filament bends due to external loading) and is able to account for large, unsteady displacements. In addition, our analysis yields explicit conditions on the external loading that must be satisfied for a straight helix axis. In the small-deformation limit, we exactly recover the coupled wave equations used to describe the free vibrations of helical coil springs, thereby justifying previous equivalent-rod approximations in which linearised stiffness coefficients are assumed to apply locally and dynamically. We then illustrate our theory with two loading scenarios: (I) a heavy helical rod deforming under its own weight; and (II) the dynamics of axial rotation (twirling) in viscous fluid, which may be considered as a simple model for a bacteria flagellar filament. In both scenarios, we demonstrate excellent agreement with solutions of the full Kirchhoff rod equations, even beyond the formal limit of validity of the ‘highly-coiled’ assumption. More broadly, our analysis provides a framework to develop reduced models of helical rods in a wide variety of physical and biological settings, and yields analytical insight into their elastic instabilities. In particular, our analysis indicates that tensile instabilities are a generic phenomenon when helical rods are subject to a combination of distributed forces and moments.我们研究受分布力和力矩作用的细长螺旋弹性杆。聚焦于螺旋轴保持直的情况，我们采用多尺度的方法从Kirchhoff杆方程中系统地推导出“等效杆”理论：螺旋丝被描述为自然直的杆（与螺旋轴对齐），其拉伸和扭转变形是耦合的。重要的是，我们的分析在“高度卷曲”灯丝的极限下是渐进精确的（即，当螺旋波长远小于灯丝由于外部负载而弯曲的特征长度尺度时），并且能够解释大的非定常位移。此外，我们的分析得出了对于直螺旋轴必须满足的外载荷的明确条件。在小变形极限下，我们精确地恢复了用于描述螺旋螺旋弹簧自由振动的耦合波动方程，从而证明了先前的等效杆近似，其中线性化刚度系数被假设局部和动态地应用。然后，我们用两种加载场景来说明我们的理论：(I)一根重的螺旋杆在自身重量下变形；（II）粘性流体中轴向旋转（旋转）的动力学，这可以被认为是细菌鞭毛细丝的简单模型。在这两种情况下，我们证明了与完整基尔霍夫杆方程的解的良好一致性，甚至超出了“高度卷曲”假设的有效性的正式限制。更广泛地说，我们的分析为在各种物理和生物环境下开发螺旋杆的简化模型提供了一个框架，并对其弹性不稳定性产生了分析见解。特别是，我们的分析表明，当螺旋杆受到分布力和力矩的组合时，拉伸不稳定性是一种普遍现象。Modeling deformation, recovery, and recrystallization of tantalum using a higher order elasto-viscoplastic self-consistent modelIftekhar A. Riyad, Bjørn Clausen, Daniel J. Savage, Youngung Jeong, Donald W. Brown, Marko Knezevicdoi:10.1016/j.jmps.2024.105925用高阶弹粘塑性自洽模型模拟钽的变形、恢复和再结晶In this work, dislocation density-based recovery and recrystallization models are implemented in an incremental elasto-viscoplastic self-consistent (ΔEVPSC) crystal plasticity model to interpret and predict ex-situ and in-situ thermo-mechanical and neutron diffraction datasets pertaining to deformation, recovery, and recrystallization behavior of pure Ta. A dislocation density-based hardening law available in ΔEVPSC is appropriately modified to enable a temperature dependent modeling of static recovery during heating. The ΔEVPSC model is further extended to calculate the second moments of stress incrementally in each grain. The second moments of stress are used to calculate the second moments of lattice spin, which are then used to calculate the intragranular misorientation spreads. The intragranular misorientation spreads developing during plastic deformation of grains are used to conceive transition bands and grain boundary nucleation mechanisms during recrystallization. The nucleation of new grains during recrystallization is also sensitive to annealing temperature. The implementations are validated by simulating elasto-plastic compression along two directions and subsequent static recovery/recrystallization data of Ta. Good agreement with the measured mechanical and diffraction data is achieved in terms of predicting the evolution of flow response, lattice strains during deformation, dislocation density during recovery, and texture during deformation and recrystallization with unique sets of fitted parameters. A rolling and subsequent full recrystallization of Ta is additionally simulated to demonstrate the applicability and versatility of the developed model.在本工作中，基于位错密度的回复和再结晶模型被应用于增量弹性-黏塑性自洽（ΔEVPSC）晶体塑性模型中，以解释和预测纯Ta的变形、回复和再结晶行为的离体和在体热-机械和中子衍射数据。ΔEVPSC模型中可用的基于位错密度的硬化定律被适当修改，以实现加热过程中静态回复的温度依赖性建模。该模型进一步扩展以逐粒计算应力的二阶矩。二阶矩用于计算晶格旋转的二阶矩，然后用于计算粒内取向扩散。在晶粒塑性变形过程中形成的粒内取向扩散用于设想再结晶过程中的过渡带和晶界形核机制。再结晶过程中新晶粒的形核还受退火温度的影响。这些实施方案通过沿两个方向进行弹性-塑性压缩模拟和随后的钛静态恢复/再结晶数据验证。在预测流动响应、变形过程中的晶格应变、恢复过程中的位错密度以及变形和再结晶过程中的织构演变方面，与测量的机械和衍射数据达到了良好的一致性。通过使用独特的拟合参数集，实现了对钛轧制和随后的完全再结晶过程的模拟，以展示该模型的适用性和灵活性。Viscous solvent effect on fracture of predamaged double-network gels examined by pre-notch and post-notch crack testsYong Zheng, Jian Ping Gongdoi:10.1016/j.jmps.2024.105926通过缺口前后裂纹试验研究了黏性溶剂对预损伤双网凝胶断裂的影响Double network (DN) gels, composed of two interpenetrating polymer networks with contrasting properties, garnered considerable attention since their invention due to large resistances to crack initiation and propagation. This study systematically investigates the effect of viscous solvent on the fracture behavior of DN gels through pre-notch and post-notch crack tests conducted on both water-swollen and ethylene glycol (EG)-swollen DN gels. Fracture energy analysis reveals that the chain dynamics changed by viscous solvent EG would remarkably reduce the two individual fracture energy contributions Γbulk and Γtip, originating from the energy dissipation in the bulk and in the crack tip vicinity, respectively. Furthermore, we observed that chain dynamics influence crack propagation behaviors and the molecular orientation of network strands ahead of crack tips in DN gels. Examination of the retardation patterns ahead of propagating crack tips allows for the analysis of the molecular orientation of network strands. Unusual butterfly-like retardation patterns were observed for the EG-swollen DN gels, in stark contrast to the conventional damage zone patterns seen in water-swollen DN gels. This suggests that the slowed chain dynamics induced by the viscous solvent EG lead to significant viscoelastic mechanical responses ahead of crack tips, which governs the stress/strain fields at the crack tip. This study offers valuable insights into the underlying toughening mechanism of DN gels, particularly regarding the effect of polymer chain dynamics. The experimental analysis, integrating findings on fracture energy contributions, crack propagation behaviors, and retardation observations from both pre-notch and post-notch crack tests, could be applied to characterize other soft materials with diverse toughening mechanisms, thereby aiding in the design and application of future soft materials.双网络（DN）凝胶是由两种具有不同性能的互穿聚合物网络组成的，自发明以来，由于其对裂纹的产生和扩展具有很大的阻力而引起了人们的广泛关注。本研究通过对水膨胀型和乙二醇膨胀型DN凝胶进行缺口前和缺口后的裂缝试验，系统地研究了粘性溶剂对DN凝胶断裂行为的影响。断裂能分析表明，黏性溶剂EG改变的链动力学会显著降低两个单独的断裂能贡献Γbulk和Γtip，分别来自体和裂纹尖端附近的能量耗散。此外，我们观察到链动力学影响了DN凝胶中裂纹扩展行为和裂纹尖端前网络链的分子取向。在裂纹尖端传播之前检查延迟模式，可以分析网络链的分子取向。在鸡蛋肿胀的DN凝胶中观察到不寻常的蝴蝶样延迟模式，与水肿胀的DN凝胶中观察到的常规损伤区模式形成鲜明对比。这表明，黏性溶剂EG诱导的链动力学变慢导致裂纹尖端前出现明显的粘弹性力学响应，这决定了裂纹尖端的应力/应变场。这项研究为DN凝胶的潜在增韧机制提供了有价值的见解，特别是关于聚合物链动力学的影响。该实验分析综合了缺口前和缺口后裂纹试验的断裂能贡献、裂纹扩展行为和延迟观察结果，可用于表征其他具有不同增韧机制的软材料，从而有助于未来软材料的设计和应用。Three-dimensional fracture mechanics model of conch shells with hierarchical crossed-lamellar structuresQinghua Meng, Yuan Gao, Yier Guo, Qi Zhang, Yin Shu, Jason T. Harris, Qiang Fu, Xinghua Shidoi:10.1016/j.jmps.2024.105929具有分层交叉层状结构的海螺壳三维断裂力学模型Conch shells, characterized by a highly mineralized hierarchical crossed-lamellar structure that represents the pinnacle of molluscan evolution, exhibit exceptional crack resistance to protect their soft bodies from predatorial attacks. In this paper, we present a three-dimensional fracture mechanics model to establish a correlation between fracture toughness and the crossed-lamellar structure, elucidating the hierarchical crack bridging mechanism of aragonite lamellae. We find that increased fracture toughness is achieved through the energy dissipation contributed by the interfacial debonding of both first-order and second-order lamellae. The conch shells demonstrate outstanding resistance to cracking in two principal directions, featuring a locally stacked structure of flat plates that effectively withstand complex loads. The vertically alternating stacking structure of macroscopic layers of equal thickness inspires a biomimetic design with more balanced mechanical properties, accompanied by enhanced crack resistance observed as the lamellae become thinner. The theoretical results are in good agreement with relevant experimental measurements. This work not only sheds light on the physical mechanisms responsible for the remarkable fracture toughness of crossed-lamellar structures but also provides guidelines for designing high-performance biomimetic structural materials.海螺壳的特点是高度矿化的分层交叉层状结构，代表了软体动物进化的顶峰，表现出非凡的抗裂性，以保护其柔软的身体免受捕食者的攻击。本文建立了一个三维断裂力学模型，建立了断裂韧性与交叉片层结构之间的关系，阐明了文石片层的分层裂缝桥接机制。我们发现，断裂韧性的增加是通过一阶和二阶片层的界面剥离所带来的能量耗散来实现的。海螺壳在两个主要方向上表现出出色的抗裂性，具有局部堆叠的平板结构，可以有效地承受复杂的载荷。等厚度宏观层的垂直交替堆叠结构激发了具有更平衡力学性能的仿生设计，同时随着片层变薄，抗裂能力增强。理论计算结果与相关实验测量结果吻合较好。这项工作不仅揭示了交叉片层结构具有显著断裂韧性的物理机制，而且为高性能仿生结构材料的设计提供了指导。International Journal of PlasticityFast Fourier transform approach to Strain Gradient Crystal Plasticity: Regularization of strain localization and size effectAmirhossein Lame Jouybari, Samir El Shawish, Leon Cizeljdoi:10.1016/j.ijplas.2024.104153应变梯度晶体塑性的快速傅立叶变换方法：应变局部化和尺寸效应的正则化The Strain Gradient Crystal Plasticity (SGCP), based on cumulative shear strain, is developed to regularize and simulate the size effect behavior of polycrystalline aggregates, specifically in the formation of localization bands in terms of slip and kink bands, influenced by strain softening during the initial stages of plastic deformation. In this respect, the thermodynamically consistent derivation of the SGCP equations is presented, establishing their connection to the kinematics of classical crystal plasticity (CCP) framework. The governing balance equations are solved using the fixed-point algorithm of the fast Fourier transform (FFT)-homogenization method, involving explicit coupling between the classical and SGCP balance equations. To address this problem, a strong 21-voxel finite difference scheme is established. This scheme is considered to solve the higher order balance equation inherent to SGCP. Additionally, three types of interface conditions are implemented to explore the impact of grain boundaries on the transmission of localization bands. These conditions yield consistent intragranular/transgranular localization patterns in the MicroFree and MicroContinuity cases, while in the MicroHard condition all localization bands are intragranular with stress concentrations appearing at the grain boundaries. Analytical solutions corresponding to different material behaviors are developed and compared with numerical results to validate the numerical implementation of the FFT fixed-point algorithm. It is observed that both the macroscopic behavior and microscopic variables in CCP framework are highly influenced by grid resolutions (non-objective), leading to numerical instabilities arising from the material softening and subsequent formation of localization bands, both in single crystals and polycrystalline aggregates. Remarkably, the developed SGCP model provides results that are independent of grid resolutions (objective) and effectively regularizes the material behavior on local scale. Moreover, the non-local parameter of the model is capable of controlling the localization band widths. Finally, the proposed SGCP model, together with employed MicroHard condition on grain boundaries, is demonstrated to qualitatively reproduce main microstructural features of irradiated polycrystalline materials.基于累积剪切应变的应变梯度晶体塑性（SGCP）是为了规范和模拟多晶聚集体的尺寸效应行为，特别是在塑性变形初始阶段受应变软化影响的滑移和扭结局部化带的形成。在这方面，提出了SGCP方程的热力学一致性推导，建立了它们与经典晶体塑性（CCP）框架的运动学的联系。控制平衡方程采用快速傅立叶变换(FFT)-均匀化方法的不动点算法求解，涉及经典平衡方程与SGCP平衡方程之间的显式耦合。为了解决这个问题，建立了一个强21体素有限差分格式。该方案被认为是解决SGCP固有的高阶平衡方程。此外，采用三种类型的界面条件来探索晶界对局域化波段传输的影响。这些条件在MicroFree和MicroContinuity情况下产生一致的晶内/穿晶定位模式，而在MicroHard条件下，所有的定位带都在晶内，应力集中出现在晶界处。给出了不同材料特性对应的解析解，并与数值结果进行了比较，验证了FFT不动点算法的数值实现。观察到，CCP框架中的宏观行为和微观变量都受到网格分辨率（非客观）的高度影响，导致单晶和多晶聚集体中由于材料软化和随后形成的局部化带而产生的数值不稳定性。值得注意的是，所开发的SGCP模型提供了独立于网格分辨率（目标）的结果，并有效地在局部尺度上规范了材料的行为。此外，模型的非局部参数能够控制局部化带宽。最后，本文提出的SGCP模型，结合晶界上的MicroHard条件，可以定性地再现辐照多晶材料的主要显微组织特征。Thin-Walled StructuresExperimental investigation on hysteretic properties and applications in beam-column connections of shape memory alloy platesYi Su, Jin Di, Xuhong Zhou, Bin Han, Fengjiang Qin, Long Hu, Jie Wangdoi:10.1016/j.tws.2024.112650形状记忆合金板滞回特性及在梁柱连接中的应用试验研究Shape memory alloy (SMA) plates have demonstrate significant application prospects in seismic structures owing to their excellent mechanical behaviour and section adaptability. In this study, the mechanical properties and manifestations of SMA plates, particularly their cyclic tension-release behaviour, were systematically investigated. Analysis results of peak strength, self-centring capacity, and energy dissipation capacity showed that thickness, temperature, and loading protocol affect the hysteretic properties of SMA plates. Furthermore, an effective training scheme of constant 4% tensile strain, which can significantly increase the ultimate strength and self-centring capacity, was suggested for SMA plates to withstand cyclic tensile loads. Subsequently, a beam-column connection equipped with SMA plates was designed, and a set of quasi-static tests and numerical validations were conducted. The results verified the excellent self-centring capacity of the SMA plates, and the superiority and potential of applying SMA plate to aseismic structures were confirmed. Simultaneously, the SMA plates exhibited a lower energy dissipation capacity than the commonly used Q160 and ALA plates, which indicates that paralleling with other energy dissipation members is beneficial for improving the hysteretic properties of structures.形状记忆合金（SMA）板具有良好的力学性能和截面适应性，在抗震结构中具有重要的应用前景。在本研究中，系统地研究了SMA板的力学性能和表现，特别是其循环张力释放行为。峰值强度、自定心能力和能量耗散能力分析结果表明，厚度、温度和加载方式对SMA板的滞回性能有影响。此外，提出了恒定4%拉伸应变的有效训练方案，可以显著提高SMA板的极限强度和自定心能力，以承受循环拉伸载荷。随后，设计了一种安装SMA板的梁柱连接，并进行了一组准静力试验和数值验证。结果验证了SMA板具有良好的自定心能力，证实了SMA板应用于抗震结构的优越性和潜力。同时，与常用的Q160和ALA板相比，SMA板的耗能能力较低，这表明与其他耗能构件并联有利于改善结构的滞回性能。Experimental and numerical investigation on cyclic behavior of Q1100 ultra-high strength steel H-section compressive-bending members about strong-axisYun Zhang, Lu Yang, Kelong Xudoi:10.1016/j.tws.2024.112651Q1100超高强度钢h型钢强轴压弯构件循环性能试验与数值研究Q1100 refers to ultra-high strength steel (UHSS) with a nominal yield strength of 1100 MPa. Hysteretic tests were conducted on seven Q1100 UHSS H-section welded columns to assess their hysteretic performance. The hysteretic performance was evaluated through hysteresis curves, damage phenomena, energy dissipation, ductility, and load-carrying capacity. The impact of the width-to-thickness ratio and axial pressure ratio on the hysteretic behavior was also investigated. A validated finite element model was utilized to analyze the hysteresis behavior, influencing factors, and the applicability of Eurocode 3 width-to-thickness ratio limits, resulting in proposed seismic design recommendations.Q1100是指标称屈服强度为1100mpa的超高强度钢（UHSS）。对7根Q1100 UHSS h型钢焊接柱进行了滞回试验，评价了其滞回性能。通过滞回曲线、损伤现象、能量耗散、延性和承载能力来评价其滞回性能。研究了宽厚比和轴压比对滞回特性的影响。利用经过验证的有限元模型分析了迟滞行为、影响因素以及欧洲规范3宽厚比限制的适用性，从而提出了抗震设计建议。Shear buckling behaviour of beams with partial-depth stiffeners at the supportGábor Hajdú, Hartmut Pasternakdoi:10.1016/j.tws.2024.112622支撑处部分深度加劲梁的剪切屈曲行为This paper presents the findings from experimental tests and numerical simulations on plate girders with various end post configurations. While EN 1993-1-5:2024 provides design rules for both rigid and non-rigid end posts, it does not address the shear resistance of partially stiffened webs. The use of partial-depth stiffeners faces risks due to the lack of thorough investigation into their mechanical behaviour. To explore this issue, small numbered experimental tests and large numbered parametric studies on beams with different web slenderness were conducted using advanced numerical simulations. The results indicated that the shear buckling capacity of girders is lower than the design recommendation when the web stiffener height is less than 50% of the web height. For girders with full-height stiffeners, EN 1993-1-5:2024 yields safe results. The accuracy of the EN 1993-1-5:2024 design rule for partially stiffened beams was also evaluated and new and shear buckling design curves were proposed for girders with partial-depth stiffeners.本文介绍了不同端柱结构板梁的试验结果和数值模拟结果。虽然EN 1993-1-5:2024提供了刚性和非刚性端柱的设计规则，但它没有解决部分加劲腹板的抗剪能力。由于缺乏对其力学行为的彻底调查，部分深度加强筋的使用面临风险。为了探讨这一问题，采用先进的数值模拟方法，对不同腹板长细比的梁进行了小数量实验试验和大数量参数化研究。结果表明，当腹板加劲高度小于腹板高度的50%时，梁的抗剪屈曲能力低于设计推荐值。对于全高加劲梁，EN 1993-1-5:2024给出了安全结果。对en1993 -1-5:2024部分加劲梁设计规范的精度进行了评价，并对部分加劲梁提出了新的抗剪屈曲设计曲线。Stretch-induced wrinkling analysis and experimental validation of creased membranesWang Zhong, Baoyan Duan, Jingli Dudoi:10.1016/j.tws.2024.112644拉伸致皱膜分析及实验验证Creases and wrinkles are crucial factors affecting the accuracy of membrane structures. In this paper, we study the stretch-induced wrinkling of creased membrane based on a proposed planar crease model by characterizing the crease as an orthotropic rigid strip with effective bending stiffness and initial stress. A control equation of wrinkling of a stretched rectangular membrane with a vertical crease is deduced to understand the crease-wrinkle interaction. Then, a set of scaling laws for the wrinkles is discussed in detail, and it is concluded that the ratio of the bending stiffness of the crease to that of the membrane is the key influence factor. Furthermore, the analysis reveals that wrinkling in the small-strain stage is a localized wrinkling behavior independent of the crease parameters. The wrinkling wavelength and amplitude at large strains decrease with increasing crease angle. Finally, experiments verify the correctness and validity of the theoretical model and analytical method.折痕和起皱是影响膜结构精度的关键因素。本文基于平面折痕模型，将折痕描述为具有有效弯曲刚度和初始应力的正交各向异性刚性条，研究了拉伸引起的折痕膜的起皱。推导了带垂直折痕的矩形拉伸膜的起皱控制方程，以理解其相互作用。然后，详细讨论了褶皱的标度规律，得出褶皱与膜的弯曲刚度之比是影响褶皱性能的关键因素。此外，分析表明，小应变阶段的起皱是一种局部的起皱行为，与折痕参数无关。大应变下的起皱波长和幅度随折痕角的增大而减小。最后通过实验验证了理论模型和分析方法的正确性和有效性。A rationalized macroscopic failure criterion of composite woven fabrics for airship structuresLonglong Chen, Wujun Chendoi:10.1016/j.tws.2024.112647飞艇结构复合机织物宏观失效的合理化准则Composite woven fabrics are increasingly employed in architecture and aerospace for their excellent properties, such as lightweight, high specific strength, large surface area, and satisfactory deployability. The strength behavior is essential for various membrane structures as structural failure is serious. However, an accurate, simplified, and universal failure criterion has not been reported due to the inherent complexities of composite woven fabrics. This paper thus studies the tensile strength behaviors of airship fabrics and proposes a rationalized macroscopic failure criterion (Chen-Chen criterion) based on theoretical analysis and experimental observations. The generalized Chen-Chen criterion inherently satisfies the conditions of symmetry, dimensionless, and uniaxial tensile strength (UTS) boundary, with a maximum absolute deviation of only 1.34% for two airship fabrics. Additionally, the UTS-based criteria were derived particularly for flexible plain-weave polyesters to avoid laborious and costly biaxial strength tests. The average deviations of constant and linear Chen-Chen criteria are 6.01%, 4.91%, while that of the Norris criterion reaches 13.34%. Furthermore, the numerical implementation of the Chen-Chen criterion was demonstrated by biaxial tensile simulations. The failure strength and location predicted by the numerical analysis show good consistency with the experimental results.复合机织织物以其轻质、高比强度、大表面积和令人满意的可展开性等优异性能，越来越多地应用于建筑和航空航天领域。在结构破坏严重的情况下，各种膜结构的强度特性是至关重要的。然而，由于复合机织物本身的复杂性，目前还没有准确、简化和通用的失效准则。因此，本文对飞艇织物的抗拉强度行为进行了研究，并在理论分析和实验观察的基础上提出了合理化的宏观破坏判据（Chen-Chen判据）。广义Chen-Chen准则固有地满足对称、无因次和单轴拉伸强度（UTS）边界的条件，两种飞艇织物的最大绝对偏差仅为1.34%。此外，基于uts的标准是专门为柔性平纹编织聚酯制定的，以避免费力和昂贵的双轴强度测试。恒定和线性Chen-Chen判据的平均偏差分别为6.01%和4.91%，而Norris判据的平均偏差达到13.34%。此外，通过双轴拉伸模拟验证了Chen-Chen准则的数值实现。数值分析预测的破坏强度和破坏位置与试验结果吻合较好。Test and simulation of high temperature resistant polyamide composite with single lap single bolt connectionWei Zhao, Chenchen Lian, Wenxu Zhang, Hongfei Zhang, Tao Zhang, Peiyan Wang, Zhufeng Yuedoi:10.1016/j.tws.2024.112649单搭接单螺栓连接耐高温聚酰胺复合材料的试验与模拟The advancement of next-generation aerospace vehicles has presented new requirements and challenges for ensuring the structural integrity of aircraft components in extreme environments. Consequently, the utilization of high temperature resistant polyamide composite materials has become pivotal in the manufacturing of aerospace vehicle parts that operate under high temperatures (250 °C). As a critical connection technology for these materials, the mechanical behavior of bolted connection structures under high temperatures requires further investigation. In this paper, a combination of experimental and numerical simulation is used to investigate the load carrying capacity and failure mechanism of T700/BMP316 composite bolted joints at room temperature and 250°C. The experimental results show that the ultimate load carrying capacity of the structure at 250°C is only 13.1% lower than that of the room temperature environment, indicating that the temperature softening effect of such composites is not significant. Scanning electron microscope (SEM) and computed tomography (CT) results indicate that the structural damage modes were the crushing of the hole edge fibers and matrix due to the extrusion by the bolts, as well as the interlaminar delamination damage. Temperature effects were taken into account for the composite principal structure and finite element modeling was performed using a combination of Pinho criterion and Cohesive model. Numerical simulations allow accurate prediction of the load-displacement response and damage pattern throughout the damage evolution phase. The high temperature test results and the developed finite element model involved in this study can support the design of new-generation aerospace vehicles.下一代航空航天飞行器的发展对极端环境下飞机部件的结构完整性提出了新的要求和挑战。因此，耐高温聚酰胺复合材料的使用已成为制造在高温（250°C）下运行的航空航天飞行器部件的关键。作为这些材料的关键连接技术，螺栓连接结构在高温下的力学性能有待进一步研究。本文采用实验与数值模拟相结合的方法，研究了室温和250℃条件下T700/BMP316复合材料螺栓连接的承载能力及破坏机理。实验结果表明，250℃下结构的极限承载能力仅比室温环境下低13.1%，表明该复合材料的温度软化效果不显著。扫描电子显微镜（SEM）和计算机断层扫描（CT）结果表明，结构损伤模式为螺栓挤压对孔边缘纤维和基体的挤压，以及层间分层损伤。考虑温度对复合材料主结构的影响，采用Pinho准则和Cohesive模型相结合的方法进行有限元建模。数值模拟可以准确预测整个损伤演化阶段的载荷-位移响应和损伤模式。研究所涉及的高温试验结果和所建立的有限元模型可以为新一代航天飞行器的设计提供支持。来源：复合材料力学仿真Composites FEM