【新文速递】2025年5月9日固体力学SCI期刊最新文章

 

今日更新：International Journal of Solids and Structures 2 篇，Journal of the Mechanics and Physics of Solids 1 篇，Mechanics of Materials 1 篇，Thin-Walled Structures 7 篇

International Journal of Solids and Structures

Reflection and transmission of elastic waves from an immersed Willis slab at oblique incidence

Max Gattin, Nicolas Bochud, Giuseppe Rosi, Philip A. Cotterill, William Parnell, Salah Naili

doi:10.1016/j.ijsolstr.2025.113394

斜入射角下浸入式威利斯板弹性波的反射与传播

Elastic metamaterials allow for the control of wave propagation by exploiting local resonances in their internal structure, which lead to unconventional effective properties. However, complex phenomena like non-reciprocity and asymmetry require advanced homogenized models like the Willis model, which introduces additional coupling terms in the elastodynamics equations. The identification of the effective properties of the Willis medium has been predominantly restricted to 1D-wave propagation problems, and therefore here we extend its application to a heterogeneous, viscoelastic meta-slab under oblique wave incidence. In such a configuration, the key challenge in the parameter identification arises from the response of the medium, which is made more complex due to polarization coupling and a larger number of effective parameters. To address this, we adapt the stiffness matrix method to this configuration, enabling the analytical determination of reflection and transmission coefficients. We show how the partial inverse identification of some effective parameters can be analytically obtained by exploiting polarization decoupling at normal incidence. A numerical case study of a meta-slab with a resonant inclusion demonstrates how Willis coupling allows for the prescription of the asymmetric behavior of the meta-slab with a single set of effective parameters. Altogether, the reported methodology and results pave the way towards the complete identification of the effective properties of the Willis medium.

弹性超材料可以通过利用其内部结构中的局部共振来控制波的传播，从而获得非常规的有效特性。然而，像非互易和不对称这样的复杂现象需要先进的均质模型，如Willis模型，它在弹性动力学方程中引入了额外的耦合项。威利斯介质有效特性的识别主要局限于一维波传播问题，因此在这里我们将其应用扩展到斜波入射下的非均质粘弹性元板。在这种结构中，介质的响应是参数识别的关键挑战，由于极化耦合和有效参数数量的增加，介质的响应变得更加复杂。为了解决这个问题，我们将刚度矩阵方法应用于这种配置，从而可以解析确定反射系数和透射系数。我们展示了如何利用正入射偏振解耦解析得到一些有效参数的部分逆辨识。一个具有共振包体的元板的数值案例研究表明，威利斯耦合如何允许用一组有效参数来规定元板的不对称行为。总之，报告的方法和结果为完全确定Willis介质的有效特性铺平了道路。

Failure mechanism in stochastic network materials: The competition between fiber and crosslink failure

Nishan Parvez, Catalin R. Picu

doi:10.1016/j.ijsolstr.2025.113445

随机网络材料的失效机制：光纤和交联失效的竞争

Materials whose main structural component is a network of fibers are known collectively as Network materials and are ubiquitous in engineering and biology. Their strength is critical in many biological applications and industrial processes. Failure in network materials without embedding matrix or with a fluidic matrix is controlled by the rupture of fibers and crosslinks. This work evaluates the competition between fiber and crosslink rupture mechanisms in defining the network strength. It is shown that a single parameter – the ratio of the crosslink to fiber strengths, Γc– is sufficient to describe this physics. The mechanism dominance transition takes place in the approximate range 0.25<Γc≤1 , which is independent of other structural network parameters. The bias of Γc to values somewhat smaller than 1 is due to the fact that in an elastic network in which failure is prevented, fibers carry larger forces than the crosslinks. Network strength is proportional to the strength of the critical component (fibers or crosslinks) and, for the type of networks considered here, is proportional to the square of the network density. This relation applies equally in the parametric regimes in which one mechanism dominates, and in the transition regime. The present data provides insight into the failure mechanism of network materials and the scaling laws relevant in material design.

主要结构成分是由纤维网络构成的材料统称为网络材料，在工程和生物学领域中无处不在。其强度在许多生物应用和工业过程中至关重要。不含嵌入基质或含流体基质的网络材料的失效由纤维和交联点的断裂控制。本研究评估了纤维和交联点断裂机制在决定网络强度方面的竞争。结果表明，仅一个参数——交联点强度与纤维强度之比 Γc 即足以描述这一物理现象。机制主导转变发生在约 0.25 < Γc ≤ 1 的范围内，且与网络的其他结构参数无关。Γc 倾向于略小于 1 的值，这是因为在一个弹性网络中，若要防止失效，纤维所承受的力要大于交联点。网络强度与关键组分（纤维或交联点）的强度成正比，对于此处所考虑的网络类型，还与网络密度的平方成正比。这种关系在一种机制占主导地位的参数范围内以及过渡范围内同样适用。目前的数据为网络材料的失效机制以及材料设计中相关的缩放规律提供了见解。

Journal of the Mechanics and Physics of Solids

A phase-field fracture formulation for generalized standard materials: The interplay between thermomechanics and damage

Lampros Svolos, Quoc-Thai Tran, Ismael D. Boureima, Veronica Anghel, Krishna Garikipati, Hashem M. Mourad

doi:10.1016/j.jmps.2025.106154

广义标准材料的相场断裂公式：热力学与损伤的相互作用

Accurately modeling fracture of ductile materials poses open challenges in the field of computational mechanics due to the multiphysics nature of their failure processes. Integrating the interplay between thermodynamics and damage into ductile fracture models is vital for predicting critical failure modes. In this paper, we develop a versatile phase-field (PF) framework for modeling ductile fracture, taking into account finite-strain elasto-plasticity. The framework stems from a variational formulation of constitutive relations for generalized standard materials (GSMs), whose response is described by a Helmholtz free energy and a dissipation pseudo-potential. Its variational structure is based on a minimum principle for a functional that expresses the sum of power densities for reversible and irreversible processes. By minimizing this functional with a constraint on a von Mises yield function, we derive the evolution equation for the equivalent plastic strain and an associative flow rule. This constrained optimization problem is analytically solved for a wide class of thermo-viscoplasticity models. The key innovations of the current work include (i) a cubic plastic degradation function that accounts for a non-vanishing damage-dependent yield stress, (ii) closed-form expressions of the Helmholtz free energy and dissipation pseudo-potential for three thermo-viscoplasticity models, (iii) an extended Johnson-Cook plasticity model with a nonlinear hardening law, and (iv) a plastic work heat source that depends on the plastic degradation function and a variable Taylor-Quinney (TQ) coefficient. The capabilities of the proposed framework are tested with the aid of four ductile fracture problems, including the Sandia Fracture Challenge. In each of these problems, we examine the evolution of relevant field variables such as the PF order parameter, the equivalent plastic strain, the temperature, and the internal power dissipation density, in addition to the overall structural response quantified by the force–displacement curve. These numerical studies demonstrate that the proposed framework effectively represents ductile fracture, yielding computational results that exhibit good agreement with experimental data.

由于延性材料断裂过程的多物理场特性，对其进行精确的断裂建模是计算力学领域的一个挑战。将热力学和损伤之间的相互作用整合到韧性断裂模型中对于预测临界破坏模式至关重要。在本文中，我们开发了一个通用的相场（PF）框架来模拟韧性断裂，考虑了有限应变弹塑性。该框架源于广义标准材料（gsm）本构关系的变分公式，其响应由亥姆霍兹自由能和耗散伪势描述。它的变分结构是基于一个函数的最小值原理，该函数表示可逆和不可逆过程的功率密度之和。通过对von Mises屈服函数的约束最小化该泛函，推导出等效塑性应变的演化方程和关联流动规律。这一约束优化问题对一类广泛的热粘塑性模型进行了解析求解。当前工作的关键创新包括(i)考虑非消失损伤相关屈服应力的三次塑性退化函数，（ii）三种热粘塑性模型的亥姆霍兹自由能和耗散伪势的封闭形式表达式，（iii）具有非线性硬化规律的扩展Johnson-Cook塑性模型，以及（iv）依赖于塑性退化函数和变量Taylor-Quinney （TQ）系数的塑性功热源。通过包括Sandia裂缝挑战在内的四个韧性裂缝问题，测试了该框架的性能。在这些问题中，除了力-位移曲线量化的整体结构响应外，我们还研究了相关场变量的演变，如PF阶参数、等效塑性应变、温度和内部功耗密度。数值研究表明，该框架能有效表征韧性断裂，计算结果与实验数据吻合较好。

Mechanics of Materials

Experimental testing of V notched radially graded materials under static loading

Suhib Abu-Qbeitah, Olga Petrenko, Michele Ciavarella, Stephan Rudykh

doi:10.1016/j.mechmat.2025.105364

静载荷作用下V形缺口径向梯度材料的试验研究

The growing interest in additive manufacturing and printed materials has opened new possibilities for the development and application of Graded Materials (GMs). However, capturing the strength and fracture behavior of GMs presents challenges, as the extent to which classical theories for homogeneous materials apply remains uncertain. For example, it has been recently suggested that in the classical problem of a sharp wedge or crack loaded in-plane (mode I and/or mode II), the stress singularity can be mitigated by grading the elastic properties of the material near the notch tip according to a power-law distribution, E ∼ r β . This suggests that sharp geometrical discontinuities can exist without causing sharp stress concentrations. Under these conditions, it is conceivable that structural optimization should aim to achieve uniform stress distribution or, more specifically, consistent strength throughout the material. Since material resistance typically follows a power-law function of the elastic modulus, a state of uniform stress is not optimal. However, a state of uniform strength may also be considered less than ideal with respect to the homogeneous material since the softer material used to reduce stress concentration reduces also the strength of the specimen. Here, we report experiments conducted on V-notched specimens, varying the grading exponent β , and compare the results for homogeneous material specimens with those of GMs. We find that the cancellation of singularity effect competes with the reduction of strength due to the use of softer materials, but when the latter effect is accounted for or reduced, we observe an improvement compared to the homogeneous V-notched case. Further, when the strength-modulus exponent m = 0 , structural optimization is equivalent to minimizing stress concentration. For most materials with m < 1 , the optimal behavior occurs near this criterion. In our case, we found m ≈ 0 . 5 , which is significant because strain energy density, a function of both stress and strain, acts as a dual-purpose criterion. This criterion is similar to the σ / σ a ratio used in homogeneous materials like Rankine or Von Mises. Notably, in fatigue tests, we anticipate that the benefits of material grading will be more pronounced.

人们对增材制造和印刷材料的兴趣日益浓厚，为梯度材料的开发和应用开辟了新的可能性。然而，捕获GMs的强度和断裂行为存在挑战，因为均质材料的经典理论适用的程度仍然不确定。例如，最近有人提出，在平面内加载尖锐楔形或裂纹（I型和/或II型）的经典问题中，可以根据幂律分布E ~ r β对缺口尖端附近材料的弹性特性进行分级，从而减轻应力奇异性。这表明尖锐的几何不连续可以存在而不引起尖锐的应力集中。在这些条件下，可以想象，结构优化的目标应该是实现均匀的应力分布，或者更具体地说，在整个材料中实现一致的强度。由于材料阻力通常遵循弹性模量的幂律函数，因此均匀应力状态不是最佳状态。然而，相对于均质材料，均匀强度的状态也可能被认为不太理想，因为用于降低应力集中的较软材料也会降低试样的强度。在这里，我们报道了在v形缺口试样上进行的实验，改变了分级指数β，并将均匀材料试样的结果与GMs的结果进行了比较。我们发现，由于使用较软的材料，奇异效应的消除与强度的降低是竞争的，但是当后者的影响被考虑或减少时，我们观察到与均匀的v形切口情况相比有改善。当强度-模量指数m = 0时，结构优化相当于使应力集中最小化。对于大多数m < 1的材料，最优行为发生在该准则附近。在我们的例子中，我们发现m≈0。5，这是重要的，因为应变能密度是应力和应变的函数，可以作为双重标准。这个准则类似于在均匀材料中使用的σ / σ a比率，如朗肯或冯·米塞斯。值得注意的是，在疲劳试验中，我们预计材料分级的好处将更加明显。

Thin-Walled Structures

Supersonic flutter characteristics of perovskite solar panels integrated into nature-inspired structures

Nam V. Nguyen, Krzysztof Kamil Żur, H. Nguyen-Xuan

doi:10.1016/j.tws.2025.113358

钙钛矿太阳能板融入自然启发结构的超音速颤振特性

The utilization of renewable energy sources in modern interdisciplinary applications has become a growing trend in recent years. Additionally, the incorporation of lightweight, biologically inspired designs into aerospace applications, where minimizing mass is a vital criterion, exhibits significant potential. This paper aims to develop high-performance perovskite solar structures seamlessly integrated with a bio-inspired lightweight substrate. This innovative design not only exploits lightweight materials but also harnesses the great potential of solar energy, emphasizing eco-friendly and sustainable solutions. The advanced substrate layer is designed using triply periodic minimal surfaces (TPMS) architectures to optimize the structural performance in terms of both mass and stiffness, while the mechanical properties are further enhanced through the incorporation of graphene nanoplatelets. For the first time, the aeroelastic flutter behavior of multilayered solar panels supported by TPMS architectures and subjected to yawed supersonic flow is thoroughly examined and discussed. To estimate the aerodynamic forces induced by high-speed airflow, we utilize a first-order piston theory to characterize the fluid–structure interaction. A NURBS-based isogeometric approach in conjunction with general higher-order shear deformation theory (HSDT) is used to elucidate the aeroelastic flutter behavior of perovskite solar panels with TPMS substrate. The noteworthy vibrational performance of the TPMS-based substrate is first confirmed through comparison with two other substrates derived from commonly used cellular solid types. Additionally, the influence of a wide range of key parameters, such as boundary condition, flow angle, graphene weight fraction, substrate thickness, and aspect ratio on the supersonic flutter characteristics is systematically elucidated, resulting in several significant conclusions. The current findings can be applied to the future designs of high-performance solar-powered aircraft wings or solar arrays for space stations.

近年来，可再生能源在现代跨学科应用中的利用已成为一个日益增长的趋势。此外，将轻量化、生物启发的设计结合到航空航天应用中，其中最小化质量是一个重要标准，显示出巨大的潜力。本文旨在开发高性能钙钛矿太阳能结构与仿生轻质衬底无缝集成。这种创新的设计不仅利用了轻质材料，而且利用了太阳能的巨大潜力，强调了生态友好和可持续的解决方案。先进的衬底层采用三周期最小表面（TPMS）结构设计，以优化质量和刚度方面的结构性能，同时通过石墨烯纳米片的掺入进一步增强了机械性能。本文首次对偏航超声速流作用下TPMS结构支撑多层太阳能帆板的气动弹性颤振行为进行了深入的研究和讨论。为了估计高速气流引起的气动力，我们利用一阶活塞理论来表征流固耦合。采用基于nurbs的等几何方法，结合一般高阶剪切变形理论（HSDT），对含TPMS衬底的钙钛矿太阳能帆板气动弹性颤振行为进行了分析。通过与其他两种常用的细胞固体类型基板的比较，首先证实了tpms基板的显著振动性能。此外，系统地阐明了边界条件、流动角、石墨烯重量分数、衬底厚度和展弦比等一系列关键参数对超声速颤振特性的影响，得出了一些重要结论。目前的研究结果可以应用于未来高性能太阳能飞机机翼或空间站太阳能电池阵列的设计。

Forced vibration analysis of isogeometric Reissner–Mindlin shells using modal superposition methods

Ahmed Mostafa Shaaban, Steffen Marburg

doi:10.1016/j.tws.2025.113360

用模态叠加法分析等几何Reissner-Mindlin壳的强迫振动

This research work deals with forced vibration analysis of an advanced shell model: the isogeometric Reissner–Mindlin shell. The analysis is conducted using two modal superposition methods; the mode displacement and the mode acceleration methods. These two methods serve as model reduction techniques providing satisfactory results while saving much computation time compared to the reference model of the full method. The reduction is achieved by simplifying the global matrices and retaining only the lowest eigenfrequencies and their corresponding eigenmodes. The Reissner–Mindlin shell is well-suited for modelling thin cylindrical and spherical structures of interest. It is considered as a particular form of fully 3D solid element with a small thickness compared to other dimensions, instead of dealing with 3D elements, which are computationally expensive and may suffer from ill-conditioning. The shell mid-surface is discretized using two parametric curvilinear coordinates within a 2D isogeometric analysis, while the thickness direction is interpolated by linear Lagrange basis functions, enabling full 3D integration. This isogeometric solution is capable to model exact geometries with high continuity achieving highly accurate results while utilizing coarser meshes compared to other numerical methods. Four benchmark examples are demonstrated, beginning with a free vibration analysis to validate the computed stiffness and mass matrices of the present isogeometric solution. The obtained eigenfrequencies and the corresponding mode shapes are compared against previously published results. Subsequently, forced vibration analysis is carried out using the two comparative modal superposition methods with verifications against the reference full method.

本研究工作涉及一种先进的壳模型：等几何Reissner-Mindlin壳的强迫振动分析。采用两模态叠加法进行分析；模态位移法和模态加速度法。与全方法的参考模型相比，这两种方法在节省计算时间的同时，也提供了令人满意的模型约简技术。减少是通过简化全局矩阵和只保留最低的特征频率及其相应的特征模态来实现的。Reissner-Mindlin壳非常适合模拟感兴趣的薄圆柱形和球形结构。它被认为是一种特殊形式的全三维实体单元，与其他维度相比，它的厚度很小，而不是处理计算成本高且可能受到病态影响的三维单元。壳体中表面在二维等几何分析中使用两个参数曲线坐标进行离散化，而厚度方向则通过线性拉格朗日基函数进行插值，从而实现全三维集成。与其他数值方法相比，该等几何解能够利用更粗糙的网格来模拟具有高连续性的精确几何形状，从而获得高度精确的结果。从自由振动分析开始，演示了四个基准算例，以验证所计算的等几何解的刚度和质量矩阵。得到的特征频率和相应的模态振型与先前发表的结果进行了比较。随后，采用两种比较模态叠加法进行了强迫振动分析，并对参考全量法进行了验证。

Compression-After-Impact Behaviour of Carbon Fibre Reinforced Composites Toughened by Interleaving Polyimide Nonwoven Veils

Xiaoshan Liu, Bin Yang, Linmei Zhang, Huixin Zhu, Xiaoyu Cui, Kunkun Fu

doi:10.1016/j.tws.2025.113415

交错聚酰亚胺非织造纱增韧碳纤维增强复合材料的冲击后压缩性能

To address the deficiencies in interlaminar properties of carbon fibre reinforced polymer (CFRP) laminates, polyimide veil was incorporated between the plies. It could connect the deformed resins during loading to prevent the complete separation of adjacent layers and enhance interlaminar toughness. This study conducted both experimental and numerical investigations into the mechanical behaviour of polyimide interlaminar-toughened CFRP composites under low-velocity impact (LVI) and compression after impact (CAI) loadings. A finite element (FE) model that accounts for intralaminar damage and interlaminar delamination was developed. The model demonstrated good predictive capability for damage patterns and residual strength, with CAI strength values closely aligning with experimental data, though some discrepancies exist in the unloading portion of impact force-time histories. Subsequently, three different toughening-layer arrangement scenarios were proposed, and their effects on LVI damage and CAI strength were thoroughly examined. The findings indicated that the CAI strength of the toughened CFRP composite could be enhanced by as much as 26.09%. This study established a cost-effective analytical methodology that systematically correlates CAI strength with toughening-layer arrangement scenarios, providing optimized design strategies for composite architectures.

为了解决碳纤维增强聚合物（CFRP）层压板层间性能的不足，在层间加入了聚酰亚胺膜。它可以在加载过程中连接变形树脂，防止相邻层完全分离，提高层间韧性。本研究对聚酰亚胺层间增韧CFRP复合材料在低速冲击（LVI）和冲击后压缩（CAI）载荷下的力学行为进行了实验和数值研究。建立了考虑层间损伤和层间分层的有限元模型。该模型对损伤模式和残余强度具有较好的预测能力，CAI强度值与实验数据吻合较好，但在卸载部分存在一定差异。随后，提出了三种不同的增韧层布置方案，并对其对LVI损伤和CAI强度的影响进行了深入研究。结果表明，增韧CFRP复合材料的CAI强度可提高26.09%。本研究建立了一种具有成本效益的分析方法，系统地将CAI强度与增韧层布置方案相关联，为复合材料结构提供优化的设计策略。

Experimental and Numerical Investigation of Cold-Formed Sigma Sections Subjected to Bending and Torsion Moments

Mohamed Ismail, Ali Hammad, Sherif M. Ibrahim

doi:10.1016/j.tws.2025.113422

弯扭作用下冷弯西格玛截面的实验与数值研究

Cold-Formed Steel (CFS) has gained prominence in the construction industry due to its sustainability and cost-effectiveness. This paper explores the behavior of CFS sigma beams, a monosymmetric profile that deviates from lipped C-sections by incorporating web stiffening to enhance structural efficiency in their applications as flexural members. The beams' behavior is experimentally investigated under eccentric loading, caused by load application offset from the cross-section shear center, combining bending and torsional moments. A total of 24 experimental tests were conducted on simply supported sigma beams with various profiles subjected to eccentric load at mid-span, varying both the thickness and the loading eccentricity. The test setup was designed to induce the required loading and end conditions. These tests were then utilized in the construction of numerical models using Abaqus non-linear finite element analysis (FEA). The numerical models were validated against the experimental test results, showing good agreement in terms of ultimate strength, lateral deformations, and failure modes. Finally, a comparative analysis was conducted comparing the experimental outcomes and the GB 50018-2002 for bending and torsion. The comparison showed that the current code underestimates the sectional capacity by 67% on average. A modified design equation is proposed to predict the sigma sections subjected to both bending moment and torsion. The proposed equation improved the accuracy significantly, with only 13% lower estimation on average.

冷弯型钢（CFS）因其可持续性和成本效益在建筑行业中获得了突出地位。本文探讨了CFS西格玛梁的行为，这是一种单对称的剖面，通过结合腹板加强来提高其作为受弯构件应用的结构效率，从而偏离唇形c截面。试验研究了梁在偏心荷载作用下的受力性能，这种偏心荷载是由荷载与截面剪切中心的偏移引起的，并结合了弯矩和扭转矩。对不同截面的sigma简支梁进行了24次跨中偏心荷载试验，分别改变梁的厚度和偏心荷载。试验装置的设计是为了诱导所需的加载和结束条件。然后使用Abaqus非线性有限元分析（FEA）将这些试验用于构建数值模型。数值模型与试验结果进行了验证，在极限强度、侧向变形和破坏模式方面表现出良好的一致性。最后，将试验结果与GB 50018-2002的弯曲和扭转试验结果进行了对比分析。对比表明，现行规范平均低估截面承载力67%。提出了一个修正的设计方程来预测受弯矩和扭转作用的σ截面。提出的方程显著提高了精度，平均只降低了13%的估计。

Effect of seawater aging on collapse properties of externally pressurized CFRP cylindrical shells with circumferential defective

Xinlong Zuo, Jinwei Yu, Yongsheng Li, Wenxian Tang, Yunsen Hu

doi:10.1016/j.tws.2025.113425

海水老化对带周向缺陷的CFRP外压圆柱壳倒塌性能的影响

The effects of seawater aging on the collapse properties of externally pressurized carbon-fiber-reinforced polymer cylindrical shells with a circumferential defect were investigated. Three batches of such shells were fabricated: unaged (virgin) specimens, specimens aged for 30 or 60 days in seawater with a temperature of 20 °C or 60 °C. The geometric properties of, microscopic damage to, and collapse properties of these shells were experimentally investigated, and the results indicated that the equilibrium moisture content increased by over 20% at the immersion temperature of 60 °C. The average collapse pressure of the specimens aged for 30 and 60 days in seawater with a temperature of 60 °C were 10.122 and 9.525 MPa, respectively. The decrease in pressure capacity was considerably greater when the immersion temperature was higher. The specimens aged in seawater with a temperature of 60 °C for 60 days exhibited smooth fibers and barely any residual matrix impurities. The collapse properties of such shells were evaluated through numerical Riks analysis. Furthermore, to evaluate the collapse pressure of such aged shells, a formula was derived. The results obtained using this formula exhibited a maximum deviation of 1.5% from the corresponding experimental results.

研究了海水老化对带周向缺陷的外压碳纤维增强聚合物圆柱壳坍塌性能的影响。制作了三批此类贝壳：未老化（原始）标本，在温度为20°C或60°C的海水中老化30天或60天的标本。实验研究了这些壳的几何特性、微观损伤和崩塌特性，结果表明，在60℃的浸泡温度下，平衡含水率提高了20%以上。试件在温度为60℃的海水中时效30 d和60 d的平均崩溃压力分别为10.122和9.525 MPa。浸泡温度越高，承压能力的下降幅度越大。在温度为60℃的海水中陈化60天的试样，纤维光滑，几乎没有基体杂质残留。通过数值Riks分析，对这种壳的坍塌特性进行了评价。此外，还推导了老化壳的破坏压力计算公式。用该公式计算的结果与相应的实验结果最大偏差为1.5%。

Experimental study of end restraint coefficient of riveted stiffened panels under axial compression

Yuxin Shen, Ze Shen, Hao Sun, Xin Zhao, Caijun Xue

doi:10.1016/j.tws.2025.113426

轴压下铆接加筋板端部约束系数试验研究

In the research of calculating the inter-rivet buckling stress in riveted stiffened panel, most studies used the normative end restraint coefficient defined in the formula. However, this will result in the calculated buckling stresses being more conservative. Therefore, this paper proposes a method to calculate more accurate end restraint coefficients by combining buckling experiments and finite element simulation. Eighteen specimens were tested. The experimental variables include rivet type (countersunk and universal head), stiffener type (C-shaped and I-shaped), and rivet spacing (50 mm, 60 mm, 70 mm, and 80 mm). A new removable and replaceable fixture was also designed for the experiments. Buckling experiment results indicate: that the end constraint coefficient using countersunk rivets is increased by 2.45∼ 3.05 times, and using universal head rivets is increased by 1.43∼ 1.66 times. Wide rivet spacing could be selected to reduce structural weight and improve the economy of aircraft structural design. The error of buckling stresses between simulations and experiments is less than 5%, and the end constraint coefficients are reliable and accurate.

在计算铆接加筋板铆钉间屈曲应力的研究中，大多采用公式中定义的规范端部约束系数。然而，这将导致计算的屈曲应力更加保守。因此，本文提出了一种将屈曲实验与有限元模拟相结合的方法来计算更精确的端部约束系数。共测试了18个样本。实验变量包括铆钉类型（沉头和万向头）、加强筋类型（c型和i型）和铆钉间距（50mm、60mm、70mm和80mm）。为实验设计了一种可拆卸、可更换的夹具。屈曲试验结果表明：采用沉头铆钉的端部约束系数提高了2.45 ~ 3.05倍，采用万向头铆钉的端部约束系数提高了1.43 ~ 1.66倍。选用较宽的铆钉间距可以减轻结构重量，提高飞机结构设计的经济性。计算得到的屈曲应力与实验结果误差小于5%，端部约束系数可靠、准确。

Damage behavior of composite/metal hybrid tubes under low-velocity impact: a deep learning and mode decomposition-based acoustic emission approach

Yi-fan Su, Xing-mao Ge, Xin-Chun Zhang, Chen Chen, Lian-hua Ma, Wei Zhou

doi:10.1016/j.tws.2025.113428

基于深度学习和模态分解的复合材料/金属复合管低速冲击损伤行为

This study examined the dynamic response of CFRP/GFRP/Al hybrid tubes under transverse low-velocity impact. Four types of specimens with distinct fiber wrapping configurations were designed and subjected to impact tests using conical, hemispherical, and cylindrical impactors at two energy energies: 7.5J and 15J. Additionally, the impact damage behavior was thoroughly investigated via quasi-static indentation tests and acoustic emission (AE) technology. Notably, a novel mode decomposition-based damage identification method for composites was developed by integrating image-based AE data with deep learning techniques. The results show that sharper impactors and increased impact energies result in higher energy absorption ratios and maximum displacements, causing more severe damage destruction to the hybrid tubes. Under any given impact conditions, PC hybrid tubes (i.e., pure carbon fiber composites wrapped with aluminium tubes) always exhibit superior impact resistance. The proposed damage identification method effectively recovers the information of matrix cracking and fiber breakage hidden in AE signals, achieving an overall accuracy of 99.46%, which outperforms other CNN models based on original AE waveforms. A strong correlation exists between the damage contribution assessment derived from this method and the impact mechanical response of the hybrid tubes. In addition, the method has great potential for AE detection of other composite structures and can provide novel explanation for their damage identification and evaluation.

研究了CFRP/GFRP/Al复合材料管在横向低速冲击下的动力响应。设计了四种具有不同纤维包绕结构的试样，并使用锥形、半球形和圆柱形冲击器在7.5J和15J两种能量下进行了冲击试验。此外，通过准静态压痕试验和声发射（AE）技术深入研究了冲击损伤行为。值得注意的是，将基于图像的声发射数据与深度学习技术相结合，开发了一种基于模式分解的复合材料损伤识别方法。结果表明：冲击器越锋利，冲击能量越大，混合动力管的能量吸收比越大，最大位移越大，对混合动力管的损伤破坏越严重；在任何给定的冲击条件下，PC混合管（即纯碳纤维复合材料包裹铝管）总是表现出优异的抗冲击性。本文提出的损伤识别方法有效地恢复了隐藏在声发射信号中的基体断裂和纤维断裂信息，总体准确率达到99.46%，优于其他基于原始声发射波形的CNN模型。该方法得出的损伤贡献评估结果与混合管的冲击力学响应具有较强的相关性。此外，该方法对其他复合材料结构的声发射检测具有很大的潜力，可以为其损伤识别和评估提供新的解释。