【新文速递】2024年10月28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 2 篇，International Journal of Plasticity 1 篇，Thin-Walled Structures 4 篇

International Journal of Solids and Structures

Adaptively remeshed multiphysical modeling of resistance forge welding with experimental validation of residual stress fields and measurement processes

Andrew J. Stershic, Christopher R. D’Elia, Lauren L. Beghini, Michael R. Hill, Bjørn Clausen, Dorian K. Balch, Michael Maguire, Christopher W. San Marchi, James W. Foulk, Alexander A. Hanson, Kevin L. Manktelow

doi:10.1016/j.ijsolstr.2024.113112

电阻锻造焊接的自适应多物理模型，并对残余应力场和测量过程进行了实验验证

Welding processes used in the production of pressure vessels impart residual stresses in the manufactured component. Computational modeling is critical to predicting these residual stress fields and understanding how they interact with notches and flaws to impact pressure vessel durability. In this work, we present a finite element model for a resistance forge weld and validate it using laboratory measurements. Extensive microstructural changes, near-melt temperatures, and large localized deformations along the weld interface pose significant challenges to Lagrangian finite element modeling. The proposed modeling approach overcomes these roadblocks in order to provide a high-fidelity simulation that can predict the residual stress state in the manufactured pressure vessel; a rich microstructural constitutive model accounts for material recrystallization dynamics, a frictional-to-tied contact model is coordinated with the constitutive model to represent interfacial bonding, and adaptive remeshing is employed to alleviate severe mesh distortion. An interrupted-weld approach is applied to the simulation to facilitate comparison to displacement measures. Several approaches are employed for residual stress measurement in order to validate the finite element model: neutron diffraction, the contour method, and the slitting method. Model-measurement comparisons are supplemented with detailed simulations that reflect the configurations of the residual-stress measurement processes themselves. The model results show general agreement with experimental measurements, and we observe some similarities in the features around the weld region. Factors that contribute to model-measurement differences are identified. Finally, we conclude with some discussion of the model development and residual stress measurement strategies, including how to best leverage the efforts put forth here for other types of related weld problems.

在压力容器生产中使用的焊接工艺会在制造的部件中施加残余应力。计算建模对于预测这些残余应力场以及了解它们如何与缺口和缺陷相互作用以影响压力容器的耐久性至关重要。在这项工作中，我们提出了电阻锻造焊缝的有限元模型，并使用实验室测量对其进行了验证。广泛的微观组织变化、接近熔体的温度和焊缝界面的大局部变形对拉格朗日有限元建模提出了重大挑战。提出的建模方法克服了这些障碍，提供了高保真的仿真，可以预测制造压力容器的残余应力状态；丰富的微观结构本构模型反映了材料的再结晶动力学，摩擦-束缚接触模型与本构模型相协调表征界面键合，并采用自适应重网格来减轻严重的网格畸变。为了便于位移测量的比较，模拟中采用了断焊法。为了验证有限元模型的有效性，采用了中子衍射法、等高线法和切缝法进行残余应力测量。模型与测量结果的比较辅以反映残余应力测量过程本身结构的详细模拟。模型计算结果与实验测量结果基本一致，并观察到焊缝周围的特征有一定的相似性。确定了导致模型测量差异的因素。最后，我们对模型开发和残余应力测量策略进行了一些讨论，包括如何最好地利用这里提出的努力来解决其他类型的相关焊接问题。

Journal of the Mechanics and Physics of Solids

Statistical-Physics-Informed Neural Networks (Stat-PINNs): A machine learning strategy for coarse-graining dissipative dynamics

Shenglin Huang, Zequn He, Nicolas Dirr, Johannes Zimmer, Celia Reina

doi:10.1016/j.jmps.2024.105908

统计物理信息神经网络（stat - pinn）：一种用于粗粒度耗散动力学的机器学习策略

Machine learning, with its remarkable ability for retrieving information and identifying patterns from data, has emerged as a powerful tool for discovering governing equations. It has been increasingly informed by physics, and more recently by thermodynamics, to further uncover the thermodynamic structure underlying the evolution equations, i.e., the thermodynamic potentials driving the system and the operators governing the kinetics. However, despite its great success, the inverse problem of thermodynamic model discovery from macroscopic data is in many cases non-unique, meaning that multiple pairs of potentials and operators can give rise to the same macroscopic dynamics, which significantly hinders the physical interpretability of the learned models. In this work, we consider the problem of deriving the macroscopic (continuum) equations from microscopic (particle) data, and encode knowledge from statistical mechanics to resolve this non-uniqueness for the first time. The proposed machine learning framework, named as Statistical-Physics-Informed Neural Networks (Stat-PINNs), is here developed for purely dissipative isothermal systems. Interestingly, it only uses data from short-time particle simulations to learn the thermodynamic structure, which can in turn be used to predict long-time macroscopic evolutions. We demonstrate the approach for particle systems with Arrhenius-type interactions, common to a wide range of phenomena, such as defect diffusion in solids, surface absorption, and chemical reactions. Our results from Stat-PINNs can successfully recover the known analytic solution for the case with long-range interactions and discover the hitherto unknown potential and operator governing the short-range interaction cases. We compare our results with direct particle simulations and an analogous approach that solely excludes statistical mechanics, and observe that, in addition to recovering the unique thermodynamic structure, statistical mechanics relations can increase the robustness and predictive capability of the learning strategy.

机器学习具有从数据中检索信息和识别模式的卓越能力，已成为发现控制方程的强大工具。它越来越多地被物理学和最近的热力学所了解，以进一步揭示进化方程背后的热力学结构，即驱动系统的热力学势和控制动力学的算子。然而，尽管它取得了巨大的成功，但从宏观数据中发现热力学模型的逆问题在许多情况下是非唯一的，这意味着多对势和算子可以产生相同的宏观动力学，这严重阻碍了学习模型的物理可解释性。在这项工作中，我们考虑了从微观（粒子）数据推导宏观（连续统）方程的问题，并首次从统计力学中编码知识来解决这种非唯一性问题。提出的机器学习框架，被称为统计物理信息神经网络（stat - pinn），在这里是为纯耗散等温系统开发的。有趣的是，它只使用来自短时间粒子模拟的数据来学习热力学结构，这些数据反过来可以用来预测长期的宏观演化。我们展示了具有arrhenius型相互作用的粒子系统的方法，这种方法适用于广泛的现象，如固体中的缺陷扩散、表面吸收和化学反应。我们的统计- pin结果可以成功地恢复具有远程相互作用情况的已知解析解，并发现迄今为止未知的控制短程相互作用情况的势和算子。我们将我们的结果与直接粒子模拟和完全排除统计力学的类似方法进行了比较，发现除了恢复独特的热力学结构外，统计力学关系还可以提高学习策略的鲁棒性和预测能力。

A foundational framework for the mesoscale modeling of dynamic elastomers and gels

Robert J. Wagner, Meredith N. Silberstein

doi:10.1016/j.jmps.2024.105914

动态弹性体和凝胶的中尺度模拟的基本框架

Discrete mesoscale network models, in which explicitly modeled polymer chains are replaced by implicit pairwise potentials, are capable of predicting the macroscale mechanical response of polymeric materials such as elastomers and gels, while offering greater insight into microstructural phenomena than constitutive theory or macroscale experiments alone. However, whether such mesoscale models accurately represent the molecular structures of polymer networks requires investigation during their development, particularly in the case of dynamic polymers that restructure in time. We here introduce and compare the topological and mechanical predictions of an idealized, reduced-order mesoscale approach in which only tethered dynamic bonding sites and crosslinks in a polymer’s backbone are explicitly modeled, to those of molecular theory and a Kremer-Grest, coarse-grained molecular dynamics approach. We find that for short chain networks (∼12 Kuhn lengths per chain segment) at intermediate polymer packing fractions, undergoing relatively slow loading rates (compared to the monomer diffusion rate), the mesoscale approach reasonably reproduces the chain conformations, bond kinetic rates, and ensemble stress responses predicted by molecular theory and the bead–spring model. Further, it does so with a 90% reduction in computational cost. These savings grant the mesoscale model access to larger spatiotemporal domains than conventional molecular dynamics, enabling simulation of large deformations as well as durations approaching experimental timescales (e.g., those utilized in dynamic mechanical analysis). While the model investigated is for monodisperse polymer networks in theta-solvent, without entanglement, charge interactions, long-range dynamic bond interactions, or other confounding physical effects, this work highlights the utility of these models and lays a foundational groundwork for the incorporation of such phenomena moving forward.

基于聚合物链的离散微观网络模型通常用隐式对相互作用的对相互作用势代替显式建模的聚合物链，能够预测聚合物材料（如弹性体和凝胶）的宏观机械响应，同时比仅用本构理论或宏观实验提供的微观结构现象的洞察力更多。然而，在开发此类微观网络模型时，是否准确地反映了聚合物网络的分子结构需要进行调查，尤其是在动态聚合物随时间重构的情况下。在这里，我们介绍并比较了仅对聚合物主链上的锚定动态结合位点和交联点进行显式建模的理想化、简化微观网络方法的拓扑和机械预测，与分子理论和Kremer-Grest粗粒化分子动力学方法的预测。我们发现，对于链段长度约为12个库恩长度的短链网络（中等聚合物填充度），在相对缓慢的加载速率（与单体扩散速率相比）下，介观方法能够合理地再现分子理论和球铰链模型预测的链构象、键动力学速率和群体应力响应。此外，它能够以90%的计算成本实现这一点。这些节省使得介观模型能够访问比传统分子动力学更大的时空域，从而能够模拟大变形以及接近实验时标（例如用于动态机械分析的时标）的持续时间。尽管研究的模型是无缠结、无电荷相互作用、无长程动态键相互作用以及其他干扰物理效应的单分散聚合物网络在θ溶剂中，但这项工作凸显了这些模型的实用性，并为将来纳入此类现象奠定了基础。

International Journal of Plasticity

Stress-induced Failure Transition in Metallic Glasses

Lingyi Meng, Yuxin Zhang, Xiaochang Tang, Xiaohu Yao

doi:10.1016/j.ijplas.2024.104152

金属玻璃的应力诱发失效转变

As a novel and highly promising metal in the future application of weapons equipment and aerospace fields, metallic glasses (MGs) demonstrate intricate failure modes that encompass both the brittle and plastic characteristics when subjected to varying loading conditions. In this work, a set of Cu50Zr50 models subjected to a combined pure shear and equi-triaxial tension loading are simulated via molecular dynamics to investigate the impact of the stress state on the complex failure modes of MGs. The characteristic and critical moments when failure occurs are established under both the shear-band-induced shear failure and the micro-void-induced tensile fracture. The stress triaxiality is applied as a pivotal stress parameter that governs the transition from the shear failure mode to the tensile failure mode. The critical stress triaxiality of Cu50Zr50 MG is approximately in the range of (2.0, 3.0) when both the shear and tension failures simultaneously occur, resulting in the largest failure strain at various stress states. We subsequently obtain a nearly elliptical yield surface of the Cu50Zr50 MGs, in which the shear failure zone, tensile failure zone, and transition zone are clearly distinguished. The microstructural evolution of MGs during the failure transition is analyzed from the perspective of the specific short-range order. In contrast to the tensile deformation, icosahedral (quasi-icosahedral) clusters demonstrate a high level of shear resistance and remain stable in the shear-dominant deformations, which is confirmed as the structural origin of the stress state impacting the failure transition.

金属玻璃作为一种新型且极具应用前景的金属材料，在不同的载荷条件下表现出复杂的破坏模式，包括脆性和塑性特征。本文采用分子动力学方法模拟了纯剪切和等三轴拉伸联合加载Cu50Zr50模型，研究了应力状态对mg复合破坏模式的影响。建立了剪切带诱发剪切破坏和微孔洞诱发拉伸破坏的破坏特征和破坏发生的临界时刻。应力三轴性是控制从剪切破坏模式到拉伸破坏模式转变的关键应力参数。Cu50Zr50 MG同时发生剪切和拉伸破坏时的临界应力三轴性约在（2.0,3.0）范围内，各应力状态下的破坏应变最大。我们得到了Cu50Zr50 mg合金的近椭圆形屈服面，其中剪切破坏区、拉伸破坏区和过渡区明显区分。从特定近程阶的角度分析了镁合金在破坏转变过程中的微观组织演化。与拉伸变形相反，二十面体（准二十面体）团簇表现出高水平的抗剪切能力，并在剪切主导变形中保持稳定，这被证实是影响破坏转变的应力状态的结构根源。

Thin-Walled Structures

Damage calculation method for prestressed thin-walled aqueducts subjected to water pressure blasting

Tao Peng, Gaohui Wang, Wenbo Lu, Ming Chen, Peng Yan

doi:10.1016/j.tws.2024.112627

预应力薄壁渡槽水压爆破损伤计算方法

In recent years, the blast resistance of hydraulic structures under explosion loads has attracted more and more attention. The damage calculation method of prestressed aqueducts subjected to blasting load is still a complicated problem. For this purpose, the theory of computation of the water pressure blasting is introduced and the formula for calculating the charge weight of the water pressure blasting is presented. The accuracy of the Coupled Eulerian-Lagrangian (CEL) algorithm of the underwater explosion model is verified by the previous experiment. Then, a fully coupled three-dimensional numerical model of a prestressed aqueduct is established to acquire the dynamic performances and failure mechanisms of the prestressed aqueduct subjected to water pressure blasting. The influence of the prestress and pull rod on nonlinear dynamic performances and failure modes of a prestressed aqueduct subjected to water pressure blasting are discussed. Finally, based on the wave and material mechanics, a method of calculation for the prestressed aqueduct subjected to water pressure blasting is presented. The accuracy of the suggested method is validated by the damage mode of the prestressed aqueduct subjected to water pressure blasting under various TNT weights. The analysis results show that the proposed method can satisfy the relationship between the damage characteristics of the prestressed aqueduct to water pressure blasting and various TNT weights. 1.5 kg TNT is insufficient to completely shatter the prestressed aqueduct, while 3.5 kg TNT can cause a perfect crushing effect. 7.5 kg TNT will result in excessive fragmentation of the prestressed aqueduct and inefficient utilization of the explosive energy. The proposed damage calculation method can provide significant support for explosion analysis of the prestressed thin-walled aqueduct structure.

近年来，水工建筑物在爆炸荷载作用下的抗爆性能越来越受到人们的关注。预应力渡槽在爆破荷载作用下的损伤计算方法一直是一个比较复杂的问题。为此，介绍了水压爆破的计算理论，给出了水压爆破装药重量的计算公式。前面的实验验证了欧拉-拉格朗日（CEL）耦合算法在水下爆炸模型中的准确性。然后，建立了预应力渡槽的全耦合三维数值模型，获得了水压爆破作用下预应力渡槽的动力特性和破坏机理。讨论了预应力和拉杆对预应力渡槽在水压爆破作用下的非线性动力性能和破坏模式的影响。最后，基于波浪力学和材料力学，提出了预应力渡槽水压爆破的计算方法。通过不同TNT重量下预应力渡槽水压爆破的破坏模式，验证了该方法的准确性。分析结果表明，该方法能够满足预应力渡槽水压爆破损伤特征与不同TNT重量之间的关系。1.5 kg TNT不足以完全粉碎预应力渡槽，而3.5 kg TNT则可以产生完美的破碎效果。7.5 kg TNT将导致预应力渡槽破碎过度，爆炸能量利用效率低下。所提出的损伤计算方法可为预应力薄壁渡槽结构的爆炸分析提供重要支持。

CVAE-Based Inverse Design of Two-Dimensional Honeycomb Pentamode Metastructure for Acoustic Cloaking

Gen Li, Lihua Tang, Vladislav Sorokin, Shaohua Wang

doi:10.1016/j.tws.2024.112623

基于cvae的二维蜂窝状五模声隐身元结构反设计

In this work, a method for inverse design of two-dimensional honeycomb pentamode metastructures (HPM) based on the Conditional Variational Auto-Encoder (CVAE) is proposed to achieve acoustic cloaking. The parameter distribution of the perfect acoustic cloak with two-dimensional cylindrical Kohn-Shen-Vogelius-Weinstein (KSVW) mapping is first derived. The CVAE model framework is then established along with its loss function in terms of the design parameters of the HPM. The inverse design performance of the deep generative model is evaluated using a large number of random test samples based on finite element simulations, showing that the equivalent mechanical parameters obtained from inverse design are highly consistent with the target parameters of the perfect acoustic cloak. For the HPM cloak design given by the trained deep generative model, the total scattering cross section (TSCS) is significantly reduced as compared to the case without a cloak, thereby demonstrating the effectiveness of the CVAE-based inverse design of acoustic cloak.

本文提出了一种基于条件变分自编码器（CVAE）的二维蜂窝五模元结构（HPM）反设计方法，以实现声学隐身。首先推导了二维圆柱形Kohn-Shen-Vogelius-Weinstein （KSVW）映射的完美声斗篷的参数分布。然后根据HPM的设计参数建立CVAE模型框架及其损失函数。利用基于有限元仿真的大量随机试验样本对深度生成模型的反设计性能进行了评价，结果表明反设计得到的等效力学参数与理想声斗篷的目标参数高度一致。对于训练好的深度生成模型给出的HPM隐身设计，总散射截面（TSCS）与无隐身情况相比显著降低，从而证明了基于cvae的声学隐身反设计的有效性。

Application of Low Modulus CFRP Fabric for Steel Beams Strengthening: Experimental and Design Validation

Sivaganesh Kanmani Selvaraj, Mahendrakumar Mathialagu Madhavan

doi:10.1016/j.tws.2024.112625

低模量碳纤维布在钢梁加固中的应用：试验与设计验证

This paper presents experimental results of steel beams strengthened with low-density and low-modulus CFRP fabrics, with the objective of, (i) checking the capability of the fabric type CFRP in strengthening; (ii) assessing and understanding the failure modes for design improvement; and (iii) validating the design methods for the practical application. A total of eighteen full-scale 2.5-meter-long beams strengthened with CFRP were tested. The governing failure modes of the CFRP-strengthened steel beams were debonding, rupture, and wrinkling. The experimental moment capacities were compared with the design predictions using the limit state suggested in the ACI guideline and two new design limit states. The comparison of design predictions indicated that the use of the limit state suggested in the ACI guideline unconservatively predicted the design moment capacity while the two new design limit states were conservative. Further, it is evidently assessed that the low modulus CFRP fabric can be used for the strength upgrade of the steel beams. A detailed design example is presented for the CFRP-strengthened steel beam using different limit states for a better understanding of the readers.

本文介绍了用低密度低模量CFRP布加固钢梁的试验结果，目的是：(1)验证织物型CFRP布加固的能力；（ii）评估和了解设计改进的失效模式；（三）验证实际应用的设计方法。总共测试了18根用碳纤维增强材料加固的2.5米长全尺寸梁。cfrp加固钢梁的主要破坏模式为脱粘、断裂和起皱。采用ACI准则建议的极限状态和两种新的设计极限状态，将试验弯矩承载力与设计预测值进行了比较。设计预测结果的比较表明，采用ACI准则中建议的极限状态对设计弯矩容量的预测是不保守的，而两种新的设计极限状态对设计弯矩容量的预测是保守的。进一步评价了低模量碳纤维布用于钢梁强度提升的可行性。为使读者更好地理解cfrp加固钢梁在不同极限状态下的详细设计实例。

BUCKLING BEHAVIOUR OF HIGH-STRENGTH RETROFITTED STEEL SECTIONS MANUFACTURED BY POST HEAT-TREATMENT PROCESSES

Shadiya Jamshiyas, Konstantinos Skalomenos, Yang Ma, Marios Theofanous

doi:10.1016/j.tws.2024.112626

后热处理工艺制造的高强度加固型钢的屈曲行为

High-strength steel is increasingly popular in construction for its strength-to-weight ratio, which lowers the self-weight of structures and reduces transportation, erection, and foundation costs. Induction hardening (IH) process which involves rapid heating and cooling of the material leads to microstructural changes which enhance the hardness and strength of conventional steel, elevating it to the level of High Strength (HS) steel. This study reports an extensive investigation on the buckling response and design of IH post-treated structural steel Circular Hollow Sections (CHS). It includes tensile coupon tests, microstructural analyses, initial geometric imperfection measurements, and residual stress evaluations to determine the effects of IH treatment on CHS. Column buckling tests were conducted, and a numerical model was developed and validated against the experimental results which was utilised to study systematically the effect of imperfections. The findings suggest that the magnitude of the imperfections in IH steel sections doubled compared to the non-treated condition, whilst there was a minimal impact on the residual stresses. A comprehensive parametric study was performed using finite element models to study the structural response of IH steel CHS columns over a large range of global slendernesses and allow the assessment of the buckling curves specified in EN 1993-1-1. It was concluded that the buckling curve ‘a’ (imperfection factor, α=0.21) specified in EN 1993-1-1 provides the best buckling load predictions for the IH steel CHS columns, the response of which is superior to that of their virgin counterparts, despite the increased imperfections caused by the heat-treating process.

高强度钢在建筑中越来越受欢迎，因为它的强度与重量比降低了结构的自重，减少了运输、安装和基础成本。感应淬火（IH）过程涉及材料的快速加热和冷却，导致微观组织的变化，提高了常规钢的硬度和强度，将其提升到高强度（HS）钢的水平。本文对IH后处理型钢圆空心截面（CHS）的屈曲响应和设计进行了广泛的研究。它包括拉伸试验、微观结构分析、初始几何缺陷测量和残余应力评估，以确定IH治疗对CHS的影响。进行了柱屈曲试验，建立了数值模型，并与试验结果进行了验证，用于系统地研究缺陷的影响。研究结果表明，与未处理条件相比，IH钢截面的缺陷程度增加了一倍，而对残余应力的影响最小。使用有限元模型进行了全面的参数研究，以研究IH钢CHS柱在大范围的整体细长度上的结构响应，并允许评估en1993 -1-1规定的屈曲曲线。结果表明，en1993 -1-1中规定的屈曲曲线“a”（缺陷系数，α=0.21）为IH钢CHS柱提供了最佳的屈曲载荷预测，尽管热处理过程中缺陷增加，但其响应优于未加工钢CHS柱。