【新文速递】2023年9月26日固体力学SCI期刊最新文章

今日更新：International Journal of Plasticity 1 篇，Computer Methods in Applied Mechanics and Engineering 1 篇，Thin-Walled Structures 1 篇

International Journal of Plasticity

Damage-coupled unified constitutive modeling of 316LN stainless steel including dynamic strain aging under various tension dwell time: A macroscopic phenomenological study

Chen Gang, Li Chengcheng, Xie Mingwei, Li Bingbing, Lin Qiang

doi:10.1016/j.ijplas.2023.103764

316LN 不锈钢的损伤耦合统一构成模型，包括各种拉伸停留时间下的动态应变时效：宏观现象学研究

A damage-coupled unified constitutive model is developed for 316LN stainless steel based on the framework of the Abdel-Karim and Ohno model. In the modified model, a kinematic hardening coefficient related to accumulated plastic strain is introduced in the linear hardening term, and a damage coefficient is incorporated in the static recovery term. Meanwhile, the parameters of isotropic hardening and kinematic hardening are associated with the maximum plastic strain rate and plastic strain memory to describe the effects of dynamic strain aging and plastic strain memory. Additionally, the kinematic hardening coefficients and static recovery coefficients correlate with dwell time to simulate stress relaxation throughout the whole-life time. The comparison between the simulation and experimental results indicates the validity of the modified model under the conditions of low-cycle fatigue and creep-fatigue interaction. After identifying the material parameters using a combination of classic parameter determination methods and optimization algorithms, the cyclic stress response and hysteresis loops can be accurately simulated throughout the whole-life time.

在 Abdel-Karim 和 Ohno 模型的框架基础上，为 316LN 不锈钢建立了损伤耦合统一构成模型。在修改后的模型中，线性硬化项中引入了与累积塑性应变相关的运动硬化系数，静态恢复项中加入了损伤系数。同时，各向同性硬化和运动硬化参数与最大塑性应变速率和塑性应变记忆相关联，以描述动态应变老化和塑性应变记忆的影响。此外，运动硬化系数和静态恢复系数与停留时间相关，以模拟整个寿命期间的应力松弛。模拟结果与实验结果的对比表明，修改后的模型在低循环疲劳和蠕变-疲劳相互作用条件下是有效的。在结合使用经典参数确定方法和优化算法确定材料参数后，可精确模拟整个寿命周期内的循环应力响应和滞后环。

Computer Methods in Applied Mechanics and Engineering

Explicit synchronous partitioned scheme for coupled reduced order models based on composite reduced bases

de Castro Amy, Bochev Pavel, Kuberry Paul, Tezaur Irina

doi:10.1016/j.cma.2023.116398

基于复合缩减基的耦合缩减阶模型的显式同步分区方案

This paper formulates, analyzes and demonstrates numerically a method for the explicit partitioned solution of coupled interface problems involving combinations of projection-based reduced order models (ROM) and/or full order models (FOMs). The method builds on the partitioned scheme developed in Peterson et al. (2019), which starts from a well-posed formulation of the coupled interface problem and uses its dual Schur complement to obtain an approximation of the interface flux. Explicit time integration of this problem decouples its subdomain equations and enables their independent solution on each subdomain. Extension of this partitioned scheme to coupled ROM–ROM or ROM–FOM problems requires formulations with non-singular Schur complements. To obtain these problems, we project a well-posed coupled FOM–FOM problem onto a composite reduced basis comprising separate sets of basis vectors for the interface and interior variables, and use the interface reduced basis as a Lagrange multiplier. Our analysis confirms that the resulting coupled ROM–ROM and ROM–FOM problems have provably non-singular Schur complements, independent of the mesh size and the reduced basis size. In the ROM–FOM case, analysis shows that one can also use the interface FOM space as a Lagrange multiplier. We illustrate the theoretical and computational properties of the partitioned scheme through reproductive and predictive tests for a model advection–diffusion transmission problem.

本文阐述、分析并数值演示了一种显式分区求解耦合界面问题的方法，该方法涉及基于投影的减阶模型（ROM）和/或全阶模型（FOM）的组合。该方法以 Peterson 等人（2019）开发的分区方案为基础，从耦合界面问题的拟合公式出发，利用其对偶舒尔补码获得界面通量的近似值。该问题的显式时间积分将其子域方程解耦，使其在每个子域上都能独立求解。将这种分区方案扩展到 ROM-ROM 或 ROM-FOM 耦合问题，需要使用非邢格舒尔补集的公式。为了求解这些问题，我们将问题解决得很好的耦合 FOM-FOM 问题投影到由界面和内部变量的独立基向量集组成的复合还原基上，并将界面还原基用作拉格朗日乘法器。我们的分析证实，由此产生的 ROM-ROM 和 ROM-FOM 耦合问题具有可证明的非奇异舒尔补全，与网格大小和还原基大小无关。在 ROM-FOM 的情况下，分析表明我们也可以使用界面 FOM 空间作为拉格朗日乘法器。我们通过对模型平流-扩散传输问题的再现和预测测试，说明了分区方案的理论和计算特性。

Thin-Walled Structures

Analytical Method for Deformation and Stress Calculation of Bell-and-spigot Joints in PVC-U Pipes

Xue Xiang, Hu Shaowei, Shan Changxi, Qi Hao, Tian Xinru

doi:10.1016/j.tws.2023.111228

聚氯乙烯（PVC-U）管道钟罩和插销接头的变形和应力计算分析方法

The stable operation of water supply pipelines relies significantly on the structural safety of pipe joints. A novel analytical pipe joint structural calculation method based on the Novozhilov thin shell theory was proposed to calculate the deformation and stress of bell-and-spigot joints in unplasticized polyvinyl chloride (PVC-U) pipes under internal pressure. An equivalent stress index was established to investigate and evaluate the safety performance of pipe joints. The effects of various factors, including spigot insertion depth, the clearance between the bell and spigot, internal pressure, and different pipe nominal outside diameter (DN) and nominal pressure (PN) series, on the maximum equivalent stress of pipe joints, were thoroughly analyzed. The results indicate that the maximum equivalent stress under nominal pressure is located on the inner surface of the bell and consistently exceeds the design stress. The influence of spigot insertion depth on the maximum equivalent stress is minimal. However, as the clearance value between the bell and spigot decreases and the internal pressure increases, the maximum equivalent stress increases significantly. Pipes with smaller DN and PN series result in a higher maximum equivalent stress at the joint. The analytical method indicates that increasing pipe thickness and reinforcing the bell with continuous carbon fiber filament winding are two potentially effective methods to enhance the mechanical performance of the joint and reduce the maximum equivalent stress. This study's findings offer valuable theoretical support for designing and selecting joints in PVC-U pipelines.

供水管道的稳定运行在很大程度上取决于管道接头的结构安全。基于诺沃日洛夫薄壳理论，提出了一种新的管道接头结构分析计算方法，用于计算未塑化聚氯乙烯（PVC-U）管道中喇叭口接头在内部压力作用下的变形和应力。建立了等效应力指数，用于研究和评估管道接头的安全性能。深入分析了各种因素，包括拉钉插入深度、喇叭口与拉钉之间的间隙、内压以及不同管道公称外径 (DN) 和公称压力 (PN) 系列对管道接头最大等效应力的影响。结果表明，公称压力下的最大等效应力位于喇叭口内表面，且持续超过设计应力。拉钉插入深度对最大等效应力的影响很小。但是，随着喇叭口和拉钉间间隙值的减小以及内压的增加，最大等效应力会显著增加。DN 和 PN 系列较小的管道会导致接头处的最大等效应力增大。分析方法表明，增加管道厚度和用连续碳纤维丝缠绕加固喇叭口是提高接头机械性能和降低最大等效应力的两种潜在有效方法。这项研究结果为设计和选择 PVC-U 管道接头提供了宝贵的理论支持。