【新文速递】2024年3月13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 2 篇，International Journal of Plasticity 1 篇，Thin-Walled Structures 5 篇

International Journal of Solids and Structures

Nonlinear deformations of size-dependent porous functionally graded plates in a temperature field

A.V. Krysko, D.A. Gubaidullin, L.A. Kalutsky, V.A. Krysko

doi:10.1016/j.ijsolstr.2024.112759

温度场中与尺寸有关的多孔功能分级板的非线性变形

In this paper, the Variational Iteration Method (VIM) or Extended Kantorovich Method (EKM) is formulated for the first time for flexible porous functionally graded (PFGM) plates with different boundary conditions and geometric nonlinearity according to the theory of Theodore von Karman. Its accuracy and efficiency are demonstrated. The plate is subjected to a uniform transversal load and temperature field. The displacement field of the plate is approximated based on the classical plate theory (CTP) or Kirchhoff's plate theory. The governing equations are derived using Hamilton's principle. Modified Coupled Stress Theory (MCST) is used to account for size-dependent effects. The material properties vary with thickness and are temperature dependent. Four porosity distribution patterns are considered in this study. Several examples are solved to demonstrate the proposed algorithm. The results obtained are compared with solutions obtained by the Bubnov-Galerkin Method (BGM) in higher approximations, the Finite Difference Method (FDM) of second order accuracy, as well as with results obtained by the Finite Element Method (FEM) of other authors. The results include an analysis of the effect of size dependent parameters, porosity type pattern, porosity index, functionally graded index, temperature field and different types of boundary conditions on the stress–strain state and bending deflection of plates.

本文根据 Theodore von Karman 的理论，首次针对具有不同边界条件和几何非线性的柔性多孔功能分层板（PFGM）提出了变量迭代法（VIM）或扩展 Kantorovich 法（EKM）。该方法的准确性和高效性得到了证明。板承受均匀的横向载荷和温度场。板的位移场是根据经典板理论（CTP）或基尔霍夫板理论近似得到的。利用汉密尔顿原理推导出控制方程。修正耦合应力理论（MCST）用于考虑尺寸效应。材料特性随厚度变化，并与温度有关。本研究考虑了四种孔隙率分布模式。通过求解几个实例来演示所提出的算法。获得的结果与更高近似度的布勃诺夫-加勒金法（BGM）、二阶精度的有限差分法（FDM）以及其他作者的有限元法（FEM）获得的结果进行了比较。研究结果包括分析尺寸相关参数、孔隙率类型模式、孔隙率指数、功能分级指数、温度场和不同类型边界条件对板材应力应变状态和弯曲挠度的影响。

A fragile points method with a numerical-flux-based interface debonding model to simulate the delamination migration in composite laminates

Baoying Shen, Kailei Wang, Song Wang, Mingjing Li, Leiting Dong, Satya N. Atluri

doi:10.1016/j.ijsolstr.2024.112758

脆点法与基于数值流量的界面脱粘模型，用于模拟复合材料层压板中的分层迁移

Predicting damage in composite laminates is essential for a better utilization of the material, but it is challenging especially when the inter- and intra-ply damages are coupled. In this paper, a Fragile Points Method (FPM) with a numerical-flux-based interface debonding model is proposed to simulate the laminates’ damage. The FPM is a novel meshless method using the discontinuous Galerkin weak formulations and the point-based discontinuous polynomial trial functions. In this work, an orthotropic interface debonding model has been developed based on the numerical fluxes to simulate the mixed-mode inter- and intra-ply damage. For any interior interface in an FPM model, the interface damage is triggered when the damage criterion is satisfied and the interface is separated when the fracture energy is reached. Due to the discontinuous characteristics of the FPM, the inter- and intra-ply damage modes are introduced explicitly, and thus the coupling between them can be naturally captured. In this paper, the proposed FPM is verified by four benchmark examples for Mode I, Mode II and Mixed Mode delamination. Then the proposed method is applied to simulate the delamination migration, used as an example for the inter- and intra-ply damage. The FPM results show that this method is able to provide reliable prediction on the load–displacement curves as well as the damage and crack patterns, and the mechanism governing the delamination migration is also discussed based on the FPM results.

预测复合材料层压板的损伤对于更好地利用材料至关重要，但这一工作具有挑战性，尤其是当层间损伤和层内损伤耦合在一起时。本文提出了一种脆性点法（FPM）和基于数值流的界面脱粘模型来模拟层压板的损伤。FPM 是一种新颖的无网格方法，使用了非连续 Galerkin 弱公式和基于点的非连续多项式试函数。在这项工作中，基于数值通量建立了一个正交界面剥离模型，以模拟层间和层内的混合模式损伤。对于 FPM 模型中的任何内部界面，当满足损伤准则时，界面损伤被触发，当达到断裂能量时，界面被分离。由于 FPM 的不连续特性，层间和层内损伤模式被明确引入，因此可以自然地捕捉到它们之间的耦合。本文通过模式 I、模式 II 和混合模式分层的四个基准实例验证了所提出的 FPM。然后，以层间和层内损伤为例，将提出的方法用于模拟分层迁移。FPM 结果表明，该方法能够可靠地预测载荷-位移曲线以及损伤和裂纹模式，并根据 FPM 结果讨论了分层迁移的机理。

Journal of the Mechanics and Physics of Solids

Configurational force method enables fracture assessment in soft materials

Miguel Angel Moreno-Mateos, Paul Steinmann

doi:10.1016/j.jmps.2024.105602

通过构力法评估软材料的断裂情况

Configurational mechanics offers a framework for quantifying the tendency of defects to alter the material configuration. When applied to fracture mechanics, configurational forces can be used to quantify the propensity of cracks to propagate. An alternative, well-established approach involves analytical solutions for crack tip displacement fields. However, these solutions typically apply to a limited range of constitutive behaviors and oftentimes to the linear small strain regime. The ease of calculating configurational forces in a numerical Finite Element implementation, along with their applicability to soft fracture at large strains, motivates the study of their performance as a standalone fracture framework. In contrast to the majority of works that remain theoretical and numerical, our study includes a robust experimental approach to configurational forces at finite strains. We report tensile experiments on a soft elastomer with pre-cuts ante fracture initiation. In a first attempt to approach the J -integral via configurational forces, we explore the performance of the linear elastic fracture mechanics solutions on Pacman-shaped domains that reproduce the crack tip vicinity. Then, we implement the entire boundary value problem with three-dimensional simulations that replicate the empirical tensile deformation of the soft elastomer samples. Subsequently, the results are benchmarked against estimations of the J -integral obtained through a bespoke finite strain analytical crack tip solution. With the successful validation of the configurational force method at finite strains, we aim to establish a pipeline for the calculation of configurational forces in a standalone manner and circumventing the need for close-form analytical solutions.

构型力学为量化缺陷改变材料构型的趋势提供了一个框架。当应用于断裂力学时，构型力可用于量化裂纹扩展的倾向。另一种行之有效的方法是对裂纹尖端位移场进行分析求解。然而，这些解法通常只适用于有限范围内的构成行为，而且往往只适用于线性小应变机制。在有限元数值计算中计算构型力非常简单，而且适用于大应变下的软断裂，这促使我们对其作为独立断裂框架的性能进行研究。与大多数停留在理论和数值上的研究不同，我们的研究采用了稳健的实验方法来研究有限应变下的构型力。我们报告了一种软弹性体在断裂发生前的预切拉伸实验。在通过构型力接近 J 积分的首次尝试中，我们探索了线性弹性断裂力学解决方案在再现裂纹尖端附近的 Pacman 形域上的性能。然后，我们通过三维模拟来实现整个边界值问题，模拟软弹性体样品的经验拉伸变形。随后，我们将结果与通过定制的有限应变分析裂纹尖端解决方案获得的 J 积分估算结果进行比对。随着有限应变下构型力方法的成功验证，我们的目标是建立一个独立的构型力计算管道，从而避免对近似形式分析解决方案的需求。

Mechanobiological tortuosity of blood vessels with stress-modulated growth and remodeling

Wei-Zhi Huang, Bo Li, Xi-Qiao Feng

doi:10.1016/j.jmps.2024.105605

应力调节生长和重塑的血管机械生物学迂回

The stability of blood vessels is essential for maintaining their functions, while severe blood vessel tortuosity leads to various clinical complications. The growth and remodeling of blood vessels, which are regulated by mechanical and biochemical cues, cause residual stresses that affect vessel stability. In this paper, we combine theory and simulations to study the mechanobiological behavior of blood vessels with stress-modulated growth and remodeling. Effects of the volumetric growth of the matrix and the turnover and reorientation of collagen fibers are accounted for. Linear stability analysis is first carried out to investigate the mechanobiological stability of blood vessels. By developing a finite element method that incorporates stress-modulated growth and remodeling, we validate the theoretical solution of the critical state and further capture the postbuckling evolution of blood vessels. Our results show that an increased internal pressure can lead to the thickening of the vessel wall, which stabilizes the blood vessels mechanically, whereas the effect of internal pressure on the mechanobiological buckling is nonmonotonic. Compared to the mechanical instability, the mechanobiological buckling results in a larger mode number and a shorter wavelength, as usually observed in varicose veins. Vessels during postbuckling may exhibit non-uniform wall thicknesses, in consistency with the experimental observation on tortuous aortas. These findings highlight the crucial role of mechanical remodeling in tissue morphogenesis and could deepen the understanding of mechanobiological mechanisms underlying the formation and development of blood vessel tortuosity.

血管的稳定性对维持其功能至关重要，而严重的血管迂曲会导致各种临床并发症。血管的生长和重塑受机械和生化线索的调控，会产生影响血管稳定性的残余应力。在本文中，我们结合理论和模拟，研究了受应力调控生长和重塑的血管的机械生物学行为。基质的体积增长以及胶原纤维的更替和重新定向的影响都被考虑在内。首先进行线性稳定性分析，研究血管的机械生物学稳定性。通过开发一种包含应力调制生长和重塑的有限元方法，我们验证了临界状态的理论解法，并进一步捕捉了血管屈曲后的演化过程。我们的研究结果表明，内压增加会导致血管壁增厚，从而使血管在机械上趋于稳定，而内压对机械生物学屈曲的影响是非单调的。与机械不稳定性相比，机械生物学屈曲会导致更大的模式数和更短的波长，这通常在静脉曲张中可以观察到。屈曲后的血管可能表现出不均匀的壁厚，这与迂曲主动脉的实验观察结果一致。这些发现凸显了机械重塑在组织形态发生中的关键作用，可加深对血管迂曲形成和发展的机械生物学机制的理解。

International Journal of Plasticity

Deformation behavior, twinning propensity model, and twinnability map for laser powder bed fused austenitic steel homogenized by hot isostatic pressing

Hongzhuang Zhang, Shujie Cao, Bing Li, Filippo Berto, Guian Qian, Changyou Li

doi:10.1016/j.ijplas.2024.103940

通过热等静压法均质的激光粉末床熔融奥氏体钢的变形行为、孪晶倾向模型和孪晶率分布图

Hot isostatic pressing (HIP) has emerged as a highly effective and extensively adopted technique for eliminating intrinsic flaws, mitigating residual stress, and addressing microstructural anisotropy in laser powder bed fused (L-PBF) metallic materials. However, the deformation behavior, strengthening mechanism, and associated mechanistic models of HIPed L-PBF austenitic steel remain largely unclear. Through multiple microstructural characterizations, this study determined that the primary deformation mechanism of HIPed L-PBF austenitic steel involved the emission of twinning partials from either the annealing twin boundaries or high-angle grain boundaries (HAGBs) with the decoration of extra dislocations and prismatic inclusions. A twinning propensity model was formulated based on the identified deformation mechanisms, revealing that the critical angle (θτ-crit) for twinning partial emissions ranged from 25.64° to 28.46°. By incorporating the mathematical relationship describing the force equilibrium state between trailing and twinning partials, a twinnability map considering both the crystallographic orientation and stress state (magnitude and direction) was established to guide the twinning control for desired mechanical properties. Finally, the accuracy of the twinning model and twinnability map was effectively confirmed using the microstructural results, whereas the limitations of the twinning model and twinnability map were reasonably examined through micro-defect and texture analysis. The results of this study provided a significant theoretical framework for understanding the twinning behavior of high-performance and homogeneous L-PBF metallic materials.

热等静压（HIP）已成为消除激光粉末床熔融（L-PBF）金属材料内在缺陷、减轻残余应力和解决微观结构各向异性的一种高效且被广泛采用的技术。然而，HIPed L-PBF 奥氏体钢的变形行为、强化机理和相关机理模型在很大程度上仍不清楚。通过多种微观结构特征分析，本研究确定了 HIPed L-PBF 奥氏体钢的主要变形机制涉及退火孪晶边界或高角度晶界 (HAGB) 在额外位错和棱柱夹杂物的装饰下释放孪晶部分。根据已确定的变形机制建立了孪晶倾向模型，发现临界角（θτ-crit）在 25.64° 至 28.46° 之间。通过结合描述拖曳和孪晶部分之间力平衡状态的数学关系，建立了一个同时考虑晶体学取向和应力状态（大小和方向）的可孪晶性图谱，以指导孪晶控制，实现理想的机械性能。最后，孪晶模型和孪晶率图的准确性通过微观结构结果得到了有效证实，而孪晶模型和孪晶率图的局限性则通过微缺陷和纹理分析得到了合理检验。研究结果为理解高性能均质 L-PBF 金属材料的孪晶行为提供了重要的理论框架。

Thin-Walled Structures

Crushing Performance Evaluation of Gradient Sierpinski Triangular Fractal Column

Yong Zhang, Kunyuan Li, Wenzhan Huang, Yu Chen, Yubo Hou, Liang Su, Baoxing Lin

doi:10.1016/j.tws.2024.111784

梯度 Sierpinski 三角分形柱的破碎性能评估

Thin-Walled Structures with excellent mechanical properties are the key to the protective system of the vehicle. This paper proposes a novel Sierpinski triangular fractal column with graded thickness (STFC-GT) to improve the crushing stability and energy absorption of Thin-Walled Structures. The crashworthiness of the STFC-GT is investigated through the experimental test and numerical simulation under axial crushing load. The results show that the Sierpinski triangular fractal column contributes to the energy absorption, and the graded thickness design can decrease the initial peak force. Specifically, the energy absorption of STFC-GT improves by 144.22% from 0th to 2nd. And the initial peak force of 2nd STFC-GT is 55.32% lower than that of 2nd STFC with uniform thickness. In addition, a theoretical relationship between the parameter configurations and the mean crushing force of STFC-GT are developed using the simplified super folding element theory (SSFE). The maximum error is less than 7.89% between the theoretical and numerical results. Finally, the influence of gradient types on crushing performance is investigated to determine the optimal gradient configuration and maximize the mechanical performance of the STFC. The research result provides reliable guidance for the design of a new vehicle safety protection device.

具有优异机械性能的薄壁结构是车辆保护系统的关键。本文提出了一种新颖的分层厚度西尔平斯基三角形分形柱（STFC-GT），以提高薄壁结构的挤压稳定性和能量吸收能力。通过轴向挤压载荷下的实验测试和数值模拟研究了 STFC-GT 的耐撞性。结果表明，西尔平斯基三角形分形柱有助于能量吸收，分级厚度设计可降低初始峰值力。具体来说，STFC-GT 的能量吸收率从第 0 个到第 2 个提高了 144.22%。第 2 个 STFC-GT 的初始峰值力比第 2 个均匀厚度的 STFC 低 55.32%。此外，还利用简化超折叠元素理论（SSFE）建立了 STFC-GT 参数配置与平均压碎力之间的理论关系。理论和数值结果之间的最大误差小于 7.89%。最后，研究了梯度类型对破碎性能的影响，以确定最佳梯度配置，最大限度地提高 STFC 的机械性能。研究成果为新型车辆安全保护装置的设计提供了可靠的指导。

Orthotropic mechanical properties of PLA materials fabricated by fused deposition modelling

Meiyu Li, Yanan Xu, Jianguang Fang

doi:10.1016/j.tws.2024.111800

通过熔融沉积模型制造的聚乳酸材料的各向同性力学性能

Polylactic Acid (PLA) sample manufactured by fused deposition modelling (FDM) technique is typically assumed to be transversely isotropic without a thorough examination of its orthotropy in three-dimensional space. This study investigated the mechanical orthotropy of PLA samples with two air gap levels (0 mm and -0.05 mm) and various loading directions. Tensile strength and elastic modulus were experimentally measured and the Hill48 yield model and orthotropic elastic model were calibrated. Results revealed that the anisotropy induced by interlayer bond was more pronounced than that within layer. Introducing a -0.05 mm air gap remarkably reduced voids in printed samples, enhancing the stiffness and strength of tensile samples. It also delayed the transition of fracture modes in intra-layer samples as the filament angle increased from 0 ∘ to 90 ∘ , which shifted from filament breakage to combined fracture mode and subsequently to interface failure. Despite these improvements, the inherent anisotropy of FDM printed PLA materials remained due to the oriented molecular chains and insufficient chain diffusion. The study emphasizes the importance of orthotropic mechanical models, demonstrating their reliability through calibration with acceptable accuracy.

通过熔融沉积成型（FDM）技术制造的聚乳酸（PLA）样品通常被假定为横向各向同性，而没有对其在三维空间中的正交性进行彻底研究。本研究调查了两种气隙水平（0 毫米和 -0.05 毫米）和不同加载方向的聚乳酸样品的机械正交性。实验测量了拉伸强度和弹性模量，并校准了 Hill48 屈服模型和正交弹性模型。结果表明，层间结合引起的各向异性比层内的各向异性更明显。引入-0.05 毫米的气隙显著减少了印刷样品中的空隙，提高了拉伸样品的刚度和强度。当长丝角度从 0 ∘ 增大到 90 ∘ 时，它还延迟了层内样品断裂模式的转变，即从长丝断裂转变为组合断裂模式，随后又转变为界面断裂。尽管有了这些改进，但由于分子链定向和链扩散不足，FDM 印刷聚乳酸材料的固有各向异性依然存在。该研究强调了各向同性力学模型的重要性，通过可接受精度的校准证明了其可靠性。

A high fidelity multiscale approach for Compression-After-Impact behavior of 2D triaxially braided composites

Xinying Zhu, Wei Chen, Lulu Liu, Lin Wei, Xue Chi, Gang Luo, Zhenhua Zhao

doi:10.1016/j.tws.2024.111793

二维三轴编织复合材料压缩-冲击后行为的高保真多尺度方法

In the current study, limited research has been conducted on modelling high-velocity impacts and their effect on residual strength. Though the simulation of compression after low-velocity impact are mature, these methods still have some numerical issues when utilized in the case of high-velocity impacts. Thus, a brand-new method suitable for continuous simulation of compression after high-velocity impact was implemented. As for the modelling techniques for 2DTBC, both the research on the model structure and constitutive behavior is still crude and imprecise. To address this situation, a high fidelity multiscale approach which contains a more accurate RUC model, a strain rate sensitive viscoelastic constitutive model and a novel subcell model was established. The HVI and CAI examples were conducted based on this framework and most results showed an error of less than 5% in both the simulation of impact resistance and residual performance. Also, the damage morphologies of simulated results demonstrated its capability and effectiveness.

在目前的研究中，有关高速冲击建模及其对残余强度影响的研究十分有限。虽然低速冲击后的压缩模拟已经成熟，但这些方法在用于高速冲击时仍存在一些数值问题。因此，我们采用了一种适用于高速冲击后压缩连续模拟的全新方法。至于 2DTBC 的建模技术，无论是模型结构还是构成行为的研究都还很粗糙和不精确。针对这种情况，建立了一种高保真多尺度方法，其中包含一个更精确的 RUC 模型、一个对应变速率敏感的粘弹性构成模型和一个新颖的子单元模型。在此框架基础上进行了 HVI 和 CAI 试验，大多数结果表明，在抗冲击性和残余性能模拟方面，误差均小于 5%。此外，模拟结果的损伤形态也证明了其能力和有效性。

Parallel neural network feature extraction method for predicting buckling load of composite stiffened panels

Tao Zhang, Peiyan Wang, Jianwei Fu, Suian Wang, Chenchen Lian

doi:10.1016/j.tws.2024.111797

预测复合加劲板屈曲载荷的并行神经网络特征提取方法

A novel Parallel Neural Network (PNN) feature extraction method is proposed in this paper to predict the buckling load of composite stiffened panels. The PNN effectively processes both stacking sequences and discrete variables by leveraging the parallel operation of the Recurrent Neural Network (RNN) and the Feedforward Neural Network (FNN). This approach addresses limitations of previous models, such as feature loss due to the Classical Laminate Theory (CLT) and struggled with variable length stacking sequences. A Self-attention-based Bidirectional Long Short-Term Memory network (T-Bi-LSTM) is introduced to handle variable length stacking sequences comprehensively. The T-Bi-LSTM, which incorporates self-attention and other mechanisms, improves the network's ability to capture crucial information. The dataset for training and testing is generated using a finite element model verified by the corresponding experiments, where the PNN with T-Bi-LSTM and other contrasting models are trained. The results suggest that the T-Bi-LSTM demonstrates better capability in extracting comprehensive stacking sequences than Bidirectional Long Short-Term Memory network (Bi-LSTM). Furthermore, the proposed PNN feature extraction method exhibits superior fitting ability and generalization performance than the feature extraction method based on CLT.

本文提出了一种新颖的并行神经网络（PNN）特征提取方法，用于预测复合加劲板的屈曲载荷。并行神经网络利用递归神经网络（RNN）和前馈神经网络（FNN）的并行操作，有效地处理了堆叠序列和离散变量。这种方法解决了以往模型的局限性，例如经典层压理论（CLT）导致的特征损失，以及在处理长度可变的堆叠序列时遇到的困难。我们引入了基于自注意的双向长短期记忆网络（T-Bi-LSTM），以全面处理长度可变的堆叠序列。T-Bi-LSTM 结合了自我注意和其他机制，提高了网络捕捉关键信息的能力。用于训练和测试的数据集是使用有限元模型生成的，并通过相应的实验进行了验证。结果表明，与双向长短期记忆网络（Bi-LSTM）相比，T-Bi-LSTM 在提取综合堆叠序列方面表现出更好的能力。此外，与基于 CLT 的特征提取方法相比，所提出的 PNN 特征提取方法表现出更优越的拟合能力和泛化性能。

Mechanical performance and design of aluminium alloy beam string structures

Hongbo Liu, Chuanjin Ma, Jiaojie Ying, Liulu Guo, Zhihua Chen

doi:10.1016/j.tws.2024.111798

铝合金梁串结构的机械性能和设计

Aluminium alloys are widely used in spatial structures because of their lightweight, high-strength, and favourable corrosion resistance characteristics. However, the low elastic modulus of this material results in reduced structural stability compared to that of other construction materials. Therefore, this study proposes incorporating prestress into aluminium alloy structures to improve their structural performance. In this study, two types of aluminium alloy beam string structures (ABSS) are presented along with their corresponding joints. Through static tests conducted on various ABSS joint configurations, this study assesses the in-plane bearing capacity and failure modes of the structures, revealing the mechanism by which prestressing enhances the in-plane performance of aluminium alloy beams. Specifically, this study investigates the influence mechanisms of various factors, such as the rise-span ratio, sag-span ratio, and initial cable force, on the in-plane bearing performance of an ABSS through numerical simulations. Finally, a method calculating the ultimate bearing capacity of aluminium alloy beam string structures is derived by employing the Ritz method, accompanied by design recommendations. The results demonstrate that introducing a prestress can significantly increase the load-bearing capacity by 5-6 times, and the flange-connected joint is determined as more suitable for being implemented in ABSS.

铝合金具有轻质、高强度和耐腐蚀的特点，因此被广泛应用于空间结构中。然而，与其他建筑材料相比，这种材料的弹性模量较低，导致结构稳定性降低。因此，本研究建议在铝合金结构中加入预应力，以改善其结构性能。本研究介绍了两种类型的铝合金梁串结构（ABSS）及其相应的接头。通过对各种 ABSS 接头配置进行静态测试，本研究评估了结构的平面承载能力和失效模式，揭示了预应力增强铝合金梁平面性能的机理。具体而言，本研究通过数值模拟研究了各种因素（如上升跨度比、下垂跨度比和初始拉索力）对 ABSS 平面内承载性能的影响机制。最后，利用里兹法得出了铝合金梁串结构极限承载力的计算方法，并给出了设计建议。结果表明，引入预应力可将承载能力显著提高 5-6 倍，并确定法兰连接接头更适合用于 ABSS。