【新文速递】2023年10月19日固体力学SCI期刊最新文章

今日更新：International Journal of Solids and Structures 1 篇，Journal of the Mechanics and Physics of Solids 1 篇，Mechanics of Materials 1 篇，International Journal of Plasticity 1 篇，Thin-Walled Structures 5 篇

International Journal of Solids and Structures

Phase field method based on reduced-order-homogenization for fibrous composite material

Liu Nianqi, Yuan Zifeng

doi:10.1016/j.ijsolstr.2023.112530

基于降阶均质化的纤维复合材料相场法

This manuscript proposes a novel multiscale phase filed method (PFM) based on reduced-order-homogenization (ROH) approach to investigate the damage evolution for the fibrous composite material, namely the ROH-PFM. In the ROH-PFM, the matrix phase is described by the PFM, and the fiber phase could be modeled by some other classic constitutive model. The overall response of the fibrous composite material then is obtained by averaging and homogenization approaches through the ROH framework in order to obtain the macro-scopic stress and consistent material moduli. In the present work, we derive the governing equations in terms of the displacement field and the matrix phase field. Through the ROH and the Francfort–Marigo variational principle, we can obtain the governing elliptical partial differential equation for the matrix phase field in terms of the stress states of the matrix and fiber phases. The corresponding weak form is derived, and numerical algorithm through the finite element method is derived as well. Finally, three groups of numerical simulations are selected to verify the functionality of the ROH-PFM, while the fibers are assumed to follow an isotropic continuum damage model. The numerical examples show good performance of the ROH-PFM in stating various material degradation mechanism.

本文提出了一种基于降阶均质化（ROH）方法的新型多尺度相锉法（PFM），即 ROH-PFM 法，用于研究纤维复合材料的损伤演化。在 ROH-PFM 中，基体相由 PFM 描述，纤维相可由其他经典构成模型建模。然后通过 ROH 框架的平均化和均质化方法获得纤维复合材料的整体响应，从而得到宏观应力和一致的材料模量。在本研究中，我们根据位移场和矩阵相场推导出了控制方程。通过 ROH 和 Francfort-Marigo 变分原理，我们可以根据基体和纤维相的应力状态得到基体相场的椭圆偏微分方程。推导出相应的弱式，并通过有限元法推导出数值算法。最后，选择了三组数值模拟来验证 ROH-PFM 的功能，同时假定纤维遵循各向同性的连续损伤模型。数值实例表明，ROH-PFM 在说明各种材料降解机制方面具有良好的性能。

Journal of the Mechanics and Physics of Solids

Isogeometric smooth crack-band model (isCBM) using spress-sprain relations adapted to microplane theory

Nguyen Hoang, Li Weican, Bažant Zdeněk P., Bazilevs Yuri

doi:10.1016/j.jmps.2023.105470

等地平滑裂纹带模型（isCBM），采用适应微平面理论的应力-应变关系

Recent optimum fitting of the data from eleven different types of distinctive fracture tests of quasibrittle materials, including the gap tests and the size effect tests, revealed that the crack band model (CBM) with the M7 damage constitutive law outperforms all the other existing computational fracture models for concrete. This is attributed to physically correct boundary conditions, especially those at the crack faces, to a finite width of the crack front which allows using a triaxial tensorial damage constitutive law, and to choosing for this law a realistic material behavior description, the M7. Nevertheless the CBM has limitations—the width of the crack band cannot be varied, the statistically smooth damage distribution across the band cannot be resolved, and the propagation direction is biased by the mesh orientation when a regular mesh is used. These limitations have been overcome by the smooth crack band model (sCBM), which uses unconventional homogenization of damage mechanics to yield an additional Helmholtz free energy density, called the “sprain energy”. This energy is a function of the curvature tensor (or a hessian) of the vectorial displacement field, called the “sprain curvature tensor” (or sprain tensor for brevity), which is a sum of the strain gradient tensor and, importantly, the rotation gradient tensor. But, in a previous study, difficulties arose in computational implementation—the use of constant-strain elements required the curvature to be resisted by sprain forces that represented the derivatives of sprain energy with respect to nodal displacements and had to be applied on the nodes of adjacent elements. The need for adjacent nodes is here avoided by a variational derivation of the Isogeometric Smooth Crack-Band Model (isCBM). The microplane damage constitutive model M7 for concrete is adopted, which is made possible by establishing the relations of the sprain stress (or spress, for brevity) and sprain on microplanes of arbitrary orientations. Using Isogeometric Analysis (IGA) based on non-uniform rational B-Splines (NURBS), the excessive displacement curvature and its resistance (spress) can be described by the shape functions with C1-continuity. Computational results show that the orientation bias of regular meshes is eliminated while keeping the constitutive law intact, which is important for compatibility with the existing material laws in general. In addition, comparisons with experimental data reveal that isCBM with M7 can reproduce the correspondence between the size of the fracture process zone and the fracture energy, as indicated by gap tests. Finally, the isCBM does not compromise the strain-path-dependence of material response.

最近，对准脆性材料的 11 种不同类型的独特断裂试验（包括间隙试验和尺寸效应试验）的数据进行了优化拟合，结果表明，采用 M7 损伤构成律的裂缝带模型（CBM）优于所有其他现有的混凝土计算断裂模型。这要归功于物理上正确的边界条件，尤其是裂缝面的边界条件，归功于裂缝前沿的有限宽度（允许使用三轴张量损伤构成法则），以及为该法则选择了现实的材料行为描述--M7。然而，CBM 也有其局限性--裂纹带的宽度无法改变，整个裂纹带的统计平滑损伤分布无法解析，而且在使用规则网格时，其传播方向会受到网格方向的影响。平滑裂纹带模型（sCBM）克服了这些局限性，它采用非常规的损伤力学均质化方法，产生额外的亥姆霍兹自由能密度，称为 "扭转能"。该能量是矢量位移场的曲率张量（或称赫氏张量）的函数，称为 "应变曲率张量"（或简称应变张量），它是应变梯度张量和旋转梯度张量的总和。但是，在之前的研究中，计算实施出现了困难--恒应变元素的使用要求用扭转力来抵抗曲率，而扭转力是扭转能量相对于节点位移的导数，必须施加在相邻元素的节点上。这里通过等几何平滑裂纹带模型（isCBM）的变式推导，避免了相邻节点的需要。通过建立任意方向微平面上的扭转应力（或简称为 spress）和扭转的关系，采用了混凝土微平面损伤构成模型 M7。利用基于非均匀有理 B-样条曲线（NURBS）的等距分析法（IGA），可以用具有 C1 连续性的形状函数来描述过度位移曲率及其阻力（spress）。计算结果表明，规则网格的方向偏差被消除了，同时保持了完整的构成定律，这对于与现有材料定律的一般兼容性非常重要。此外，与实验数据进行比较后发现，采用 M7 的 isCBM 可以重现间隙测试所显示的断裂过程区大小与断裂能量之间的对应关系。最后，isCBM 不会影响材料响应的应变路径依赖性。

Mechanics of Materials

A hybrid algorithm of particle swarm optimization and finite element method to identify local mesoscopic damage of concrete-like materials

Sun Bin, Li Yan, Guo Tong

doi:10.1016/j.mechmat.2023.104835

粒子群优化和有限元法的混合算法识别类混凝土材料的局部中观损伤

Meso-scale material modeling and parameter identification are still unsettled issues in the current multi-scale methods for the field of computational mechanics. In this investigation, a hybrid algorithm of particle swarm optimization and finite element method coupled with continuum damage mechanics is proposed to forecast local mesoscopic elasticity modulus and damage of concrete-like materials based on the macroscopic stress-strain relationship data curve. The algorithm establishes a bridge between mesoscopic mechanical analysis and macroscopic mechanical analysis, which can also guarantee the consistency of analysis in different scales. A representative numerical case is conducted to support the algorithm. Additionally, the effect of different divisions of representative volume element is analyzed based on the algorithm, and the recommended size of representative volume element is 5 mm. The prediction results match well with the corresponding macroscopic experimental results and mesoscopic experimental results based on the chosen recommended size of representative volume element. The effectiveness of the algorithm is verified, which can support an effective numerical tool to optimize and identify mesoscopic mechanical parameters and damage for multi-scale material modeling and analysis.

介观尺度材料建模和参数识别是目前计算力学领域多尺度方法中尚未解决的问题。本研究提出了一种粒子群优化和有限元法与连续损伤力学耦合的混合算法，基于宏观应力应变关系数据曲线预测混凝土类材料的局部中观弹性模量和损伤。该算法在介观力学分析和宏观力学分析之间架起了一座桥梁，并保证了不同尺度分析的一致性。为了支持该算法，我们进行了一个有代表性的数值案例。此外，还基于该算法分析了不同划分代表体积元素的影响，并推荐代表体积元素的尺寸为 5 毫米。根据所选的推荐代表体积元素尺寸，预测结果与相应的宏观实验结果和介观实验结果非常吻合。该算法的有效性得到了验证，可为多尺度材料建模和分析提供有效的数值工具，用于优化和识别介观力学参数和损伤。

International Journal of Plasticity

Damage and fracture behavior under non-proportional biaxial reverse loading in ductile metals: Experiments and material modeling

Wei Zhichao, Gerke Steffen, Brünig Michael

doi:10.1016/j.ijplas.2023.103774

韧性金属在非比例双轴反向加载下的损伤和断裂行为：实验和材料建模

This paper deals with a modified anisotropic stress-state-dependent plastic-damage continuum model incorporating combined hardening and softening rules to predict the plastic, damage, and fracture behavior of ductile metals under monotonic and reverse loading conditions. In the experimental part, a newly designed biaxially loaded cruciform flat HC-specimen of aluminum alloy EN AW 6082-T6 was subjected to biaxial non-proportional loading to generate a wide range of stress triaxialities during experiments. Thus, it is enabled to perform tensile, or shear monotonic and reverse loading superimposed by various preloads without unloading processes. The experimental data reveal the Bauschinger effect, the strength-differential (SD) effect, and the change in the hardening ratio after shear reverse loading. This is captured by a Drucker–Prager-type yield criterion with an extended Voce isotropic hardening and modified Chaboche’s kinematic hardening rule. In addition, the damage surface is assumed to be translated in the direction of the rate of the damage strain. The numerically predicted global force–displacement curves and local strain fields are verified in terms of the digital image correlation (DIC) technique. Moreover, the scanning electron microscopy (SEM) is used to examine the fracture surfaces and to validate the proposed damage constitutive model.

本文论述了一种改进的各向异性应力状态依赖性塑性损伤连续模型，该模型结合了硬化和软化规则，用于预测韧性金属在单调和反向加载条件下的塑性、损伤和断裂行为。在实验部分，一个新设计的双轴加载十字形平面 HC 试样（铝合金 EN AW 6082-T6）受到双轴非比例加载，在实验过程中产生了广泛的三轴应力。因此，它可以在没有卸载过程的情况下，执行由各种预加载叠加的拉伸或剪切单调加载和反向加载。实验数据揭示了鲍辛格效应、强度差（SD）效应以及剪切反向加载后硬化比率的变化。德鲁克-普拉格（Drucker-Prager）型屈服准则采用了扩展的 Voce 各向同性硬化和修正的 Chaboche 运动硬化规则。此外，假定损伤面沿损伤应变速率方向平移。数字图像相关（DIC）技术验证了数值预测的整体力-位移曲线和局部应变场。此外，还使用扫描电子显微镜（SEM）来检查断裂表面，并验证所提出的损伤构成模型。

Thin-Walled Structures

3D curved-walled same-phase chiral honeycombs with controllable compression-torsion coupling effect via variable cross-section design

Yang Kuijian, Rao Liyu, Hu Lingling, Li Zekai

doi:10.1016/j.tws.2023.111267

通过可变截面设计实现可控压缩-扭转耦合效应的三维曲壁同相手性蜂窝

Honeycombs are widely-used protective structures with exceptional properties. However, the performance improvement relying on regular configuration optimization and parametric study are relatively limited, because main plastic deformation only concentrates in folding line regions under progressive folding mode. To address this issue, 3D curved-walled same-phase chiral strategy is designed for honeycombs, and their crash performance is studied by experiments, numerical simulations, and theoretical analysis. The proposed honeycombs exhibit approximate progressive folding mode with controllable local compression-torsion coupling effect under out-of-plane loads. Therefore, the shearing energy is obviously increased, and the plastic hinge lines have been prolonged to increase bending energy. According to experimental results, the proposed honeycombs can achieve specific energy absorption SEA and energy absorption efficiency η respectively of 30.92J/g and 73.7%, which are 14.6% and 24.9% larger than traditional honeycomb with same thickness. Moreover, their mean stress is effectively estimated based on plastic hinge analysis, and the contribution of coupling effect on crashworthiness is demonstrated. Furthermore, out-of-plane thickness gradient design can be implemented to further promote the crashworthiness. The proposed honeycomb with thickness gradient of Δt/tave= 1.5 displays SEA and η respectively 10.9% and 23.1% larger than the non-gradient model under same equivalent density. This study for the first time introduces compression-torsion coupling mechanism into honeycombs, and provides a reference for developing high-performance honeycombs and expanding their potentials.

蜂窝是一种广泛使用的防护结构，具有优异的性能。然而，由于在渐进折叠模式下，主要塑性变形只集中在折叠线区域，因此依靠常规配置优化和参数研究来提高蜂窝的性能相对有限。针对这一问题，我们设计了三维曲壁同相手性策略蜂窝，并通过实验、数值模拟和理论分析对其碰撞性能进行了研究。所提出的蜂窝在平面外载荷作用下表现出近似渐进折叠模式，并具有可控的局部压缩-扭转耦合效应。因此，剪切能明显增加，塑性铰线延长，弯曲能增加。实验结果表明，所提出的蜂窝的比能量吸收 SEA 和能量吸收效率 η 分别为 30.92J/g 和 73.7%，比相同厚度的传统蜂窝分别高出 14.6% 和 24.9%。此外，根据塑性铰链分析，有效估算了它们的平均应力，并证明了耦合效应对耐撞性的贡献。此外，平面外厚度梯度设计可进一步提高耐撞性。所提出的厚度梯度为 Δt/tave= 1.5 在相同等效密度下，SEA 和 η 分别比非梯度模型大 10.9% 和 23.1%。这项研究首次在蜂窝中引入了压缩-扭转耦合机制，为开发高性能蜂窝和拓展蜂窝潜力提供了参考。

Generalized strain-based finite element for non-linear stability analysis of beams with thin-walled open cross-section

Jonker J.B.

doi:10.1016/j.tws.2023.111278

基于广义应变的有限元用于薄壁开放截面梁的非线性稳定性分析

Based on the generalized strain theory a shear-deformable finite element is developed for nonlinear stability analysis of thin-walled open-section beams in multibody systems. In this formulation a finite number of deformations, characterized as generalized strains is defined which are related to dual stress resultants in a co-rotational frame. The stiffness formulation is based on a second-order approximation of the local elastic displacement field. Timoshenko’s beam theory and Vlasov’s modified thin-walled beam theory are used to include the shear strain effects due to non-uniform bending and restrained warping torsion and their mutual coupling effects. Axial shortening associated with the Wagner Hypothesis is taken into account such that the nonlinear behaviour of the beam is predicted accurately, especially under large torsion. Coupling between bending and torsional deformation due to non-coincident centroid and shear centre is modelled using a second-order cross-section transformation matrix. Cubic Hermitian polynomials are used as shape functions for the lateral displacements and twist rotation to derive the elastic and geometric stiffness matrices. Geometric nonlinearities associated with axial elongation and bending curvatures are described by additional torsion, bending and warping-related quadratic deformation terms yielding a set of modified deformations. The inertia properties of the beam are described using both consistent and lumped mass formulations. The latter is used to model rotary and warping inertias of the beam cross-section. The accuracy and the computational efficiency of the new beam element is demonstrated in several static and dynamic examples.

根据广义应变理论，开发了一种剪切变形有限元，用于多体系统中薄壁开截面梁的非线性稳定性分析。在该公式中，定义了有限数量的变形，其特征为广义应变，与同向旋转框架中的双应力结果相关。刚度公式基于局部弹性位移场的二阶近似。Timoshenko 的梁理论和 Vlasov 的改良薄壁梁理论用于包含非均匀弯曲和受约束翘曲扭转引起的剪切应变效应及其相互耦合效应。考虑了与瓦格纳假说相关的轴向缩短，从而准确预测了梁的非线性行为，尤其是在大扭转情况下。由于中心点和剪切中心不重合，弯曲变形和扭转变形之间的耦合使用二阶横截面变换矩阵建模。立方赫尔墨斯多项式被用作横向位移和扭转旋转的形状函数，从而推导出弹性和几何刚度矩阵。与轴向伸长和弯曲曲率相关的几何非线性由额外的扭转、弯曲和翘曲相关的二次变形项来描述，从而产生一组修正变形。梁的惯性特性采用一致质量和整块质量公式进行描述。后者用于模拟梁横截面的旋转和翘曲惯性。新梁元素的精确性和计算效率在几个静态和动态示例中得到了验证。

Cross-sectional behaviour of QN1803 high-strength stainless steel I-section stub columns in fire

Xing Zhe, Wang Jiajun, San Bingbing, Jiang Mingsheng, Wu Kaidong

doi:10.1016/j.tws.2023.111282

QN1803 高强度不锈钢工字形截面支柱在火灾中的截面特性

QN1803 is a novel high-strength stainless steel with low nickel. Compared to traditional stainless steel, QN1803 high-strength stainless steel has higher yield strength and lower cost without compromising anti-corrosion properties, thus leading to a wide application prospect. This paper focuses on the cross-sectional behaviour of QN1803 high-strength stainless steel I-section stub columns in fire. A total of eight stub column tests were finished, of which six were elevated temperature tests and two were room temperature control tests. Room temperature and elevated temperature tensile coupon tests were conducted to obtain the material properties of the QN1803 high-strength stainless steel. The design methods of European fire design standard EN 1993-1-2 and the latest fire design methods proposed by Xing et al., which will be incorporated into the upcoming version of EN 1993-1-2, were evaluated in terms of accuracy and safety for the fire design of QN1803 high-strength stainless steel I-section stub columns. It was found that most ultimate cross-sectional resistances of QN1803 high-strength stainless steel I-section stub columns predicted by the design rules of European fire design standard EN 1993-1-2 were unsafe, while the ultimate cross-sectional resistances predicted by the design methods of Xing et al. were safe and accurate for the tested QN1803 high-strength stainless steel I-section stub columns.

QN1803 是一种新型低镍高强度不锈钢。与传统不锈钢相比，QN1803 高强度不锈钢具有更高的屈服强度和更低的成本，且不影响防腐性能，因此具有广泛的应用前景。本文重点研究了 QN1803 高强度不锈钢工字节短柱在火灾中的截面行为。共完成了八项短柱试验，其中六项为高温试验，两项为室温控制试验。为获得 QN1803 高强度不锈钢的材料性能，进行了室温和高温拉伸试样试验。对欧洲防火设计标准 EN 1993-1-2 的设计方法和 Xing 等人提出的最新防火设计方法进行了准确性和安全性评估，这些方法将纳入即将发布的 EN 1993-1-2 版本。结果发现，根据欧洲防火设计标准 EN 1993-1-2 的设计规则预测的 QN1803 高强度不锈钢工字节短柱的极限截面阻力大多不安全，而根据 Xing 等人的设计方法预测的 QN1803 高强度不锈钢工字节短柱的极限截面阻力则是安全和准确的。

Microstructure and mechanical properties of Inconel 718 thin walls prepared by laser direct energy deposition and selective laser melting

Meng Guiru, Gong Yadong, Zhang Jingdong, Jiang Zongze, Ren Qizhen, Zhao Jibin

doi:10.1016/j.tws.2023.111284

通过激光直接能量沉积和选择性激光熔化制备的 Inconel 718 薄壁的微观结构和机械性能

This paper systematically investigates the microstructure, crystal structure and related mechanical properties of Inconel 718 thin walls prepared by two different methods, laser direct energy deposition (LDED) and selective laser melting (SLM), which are representative technologies for laser additive manufacturing of high-performance metal parts, and compares with conventional forged parts. The microstructure of SLM-part consists of columnar and equiaxed crystals with disordered growth directions, while LDED-part is mainly composed of coarse columnar crystals that grow perpendicular to the plane of the molten pool free surface. Unlike a strong <001> texture in the LDED-part, the SLM-part has a {110} texture in the XY plane, achieving stronger tensile strength due to different grain boundary strengthening and dislocation strengthening effects, which is found by comparing with LDED and forged Inconel 718 alloy. In addition, the difference in crystallographic texture between SLM and LDED-parts results in the different mechanical property anisotropy. The comparative study of two laser additive manufacturing technologies provides guidance for an in-depth understanding about the mechanism of laser additive manufacturing high-performance metal parts.

本文系统研究了激光直接能量沉积（LDED）和选择性激光熔化（SLM）两种不同方法制备的 Inconel 718 薄壁的微观结构、晶体结构和相关力学性能，并与传统的锻造零件进行了比较。SLM 零件的微观结构由生长方向无序的柱状和等轴晶组成，而 LDED 零件主要由垂直于熔池自由表面平面生长的粗柱状晶组成。与 LDED 零件中强烈的 <001> 纹理不同，SLM 零件在 XY 平面上具有{110} 纹理，由于晶界强化和位错强化效应不同，可获得更强的抗拉强度，这一点可通过与 LDED 和锻造 Inconel 718 合金进行比较而发现。此外，SLM 和 LDED 零件结晶纹理的不同导致了不同的机械性能各向异性。两种激光增材制造技术的对比研究为深入了解激光增材制造高性能金属零件的机理提供了指导。

Experimental study on seismic behavior of high strength steel flange-plate connections with box columns

Jiang Sheng, Shi Gang, Zhang Naizhou, Hou Lintao, Zhao Huatian

doi:10.1016/j.tws.2023.111285

箱型柱高强度钢法兰板连接抗震性能试验研究

The flange-plate beam-to-column connections are a promising option for reinforced moment-resisting connections in ductile steel frames and have potential applicability in high strength steel frames. However, there have been few investigations on flange-plate connections with high strength steel box columns. In this study, experiments were conducted to evaluate the seismic behavior of high strength steel flange-plate connections with box columns. Seven specimens were designed and tested under anti-symmetrical cyclic loads, comprising three different combinations of Q355 or Q460 steel beams and Q460 or Q690 steel columns. While the expected beam failure mode was observed in five specimens, two specimens experienced ESW joints failure, and one specimen experienced CJP weld failure. These findings highlight the possible impact of welding quality defects in engineering applications. The test results about bearing capacity, rotation stiffness, deformation capacity, and energy dissipation were reported and analyzed. Under the similar design conditions, the use of higher strength steel members results in a decrease in the initial stiffness of the specimens, as well as changes in yielding modes, deformation proportion, and energy dissipation capacity. Six flange-plate connections met the deformation and bearing capacity requirements for special moment frames in AISC 341 with the ultimate story drift angle not less than 0.06 rad. The proposed criteria for determining the minimum size of flange plates was verified in this study, and design recommendations were made for flange-plate connections in high strength steel frames.

翼缘板梁柱连接是韧性钢框架中加强矩抵抗连接的一种很有前途的选择，在高强度钢框架中也有潜在的适用性。然而，关于翼缘板与高强度钢箱柱连接的研究还很少。在这项研究中，我们进行了实验，以评估高强度钢法兰板与箱形支柱连接的抗震性能。在反对称循环载荷下设计并测试了七个试样，包括 Q355 或 Q460 钢梁和 Q460 或 Q690 钢柱的三种不同组合。在五个试样中观察到了预期的梁失效模式，两个试样出现了 ESW 接头失效，一个试样出现了 CJP 焊接失效。这些发现凸显了焊接质量缺陷在工程应用中可能产生的影响。报告和分析了有关承载能力、旋转刚度、变形能力和能量耗散的测试结果。在类似的设计条件下，使用强度更高的钢构件会导致试样的初始刚度降低，屈服模式、变形比例和耗能能力也会发生变化。六个翼缘板连接满足 AISC 341 中对特殊弯矩框架的变形和承载能力要求，且极限楼层漂移角不小于 0.06 弧度。本研究验证了所提出的确定翼缘板最小尺寸的标准，并为高强度钢框架中的翼缘板连接提出了设计建议。