【新文速递】2024年7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 1 篇，Mechanics of Materials 1 篇，Thin-Walled Structures 3 篇

International Journal of Solids and Structures

Design and crashworthiness evaluation of corrugated honeycomb with multi-directional energy absorption capacity

Jiaming Wang, Zhigang Li, Haifeng Yang, Zengtao Hao, Danyang Guo, Xulong Xi, Xiaocheng Li, Huiqing Lan

doi:10.1016/j.ijsolstr.2024.113001

具有多向吸能能力的波纹蜂窝设计及耐撞性评价

In this study, three novel multi-directional energy-absorbing honeycombs were designed to meet the requirements in the crash of uncertain directions, which are named as bow-shaped honeycomb (BSHC), staggered honeycomb (SGHC) and corrugated honeycomb (CGHC). These innovative designs can significantly narrow the huge gap of the energy absorption capacity between the in-plane and out-of-plane directions of traditional honeycombs. Compression tests were conducted in three orthogonal directions. The BSHC is found to have the smallest densification strain but the highest plateau stress in each direction. The SGHC can only balance the energy absorption between out-of-plane and in-plane-x directions. The CGHC demonstrates a better densification strain and the highest multi-directional energy absorption coefficient. The detailed and equivalent finite element models of CGHC were further established and validated, and both exhibited high accuracy. Finally, a honeycomb anti-climber, with only about half length of the traditional guided honeycomb anti-climber, was designed and equipped with metro vehicles. Simulations were conducted under eccentric collision scenario. The results demonstrated that the CGHC anti-climber was capable of orderly deformation in the axial direction (out-of-plane direction) while effectively resisting the vertical (in-plane-y direction) force during collision. The energy absorption capacity of CGHC anti-climber was significantly enhanced as compared to the HEHC anti-climber under eccentric collision scenario.

本研究针对不确定方向碰撞的要求，设计了三种新型多向吸能蜂窝，分别命名为弓形蜂窝(BSHC)、交错蜂窝(SGHC)和波纹蜂窝(CGHC)。这些创新设计可以显著缩小传统蜂窝在面内方向和面外方向之间巨大的能量吸收能力差距。在三个正交方向上进行压缩试验。BSHC各方向致密化应变最小，高原应力最大。SGHC只能平衡面外和面内x方向的能量吸收。CGHC具有较好的致密化应变和最高的多向能量吸收系数。进一步建立并验证了CGHC的详细有限元模型和等效有限元模型，均具有较高的精度。最后，设计了一种蜂窝式防攀爬器，其长度仅为传统导向式蜂窝防攀爬器的一半左右。在偏心碰撞场景下进行了仿真。结果表明，CGHC防攀爬器在碰撞过程中，既能在轴向(面外方向)进行有序变形，又能有效抵抗垂直方向(面内y方向)的作用力。偏心碰撞情况下，CGHC防攀爬器的吸能能力比HEHC防攀爬器显著增强。

Journal of the Mechanics and Physics of Solids

A multiscale mechanics model for disordered biopolymer gels containing junction zones with variable length

Hashem Moosavian, Tian Tang

doi:10.1016/j.jmps.2024.105792

含变长结区的无序生物聚合物凝胶的多尺度力学模型

Disordered biopolymer gels, such as those synthesized from polysaccharide and gelatin, play an important role in biomedical applications, particularly in tissue engineering. During the gelation process of these gels, polymer chains associate in the presence of gelling agents, forming physical cross-links known as the junction zones. In contrast to rubber-like networks, the resulting network comprises two main regions: the ordered region due to the junction zones and the amorphous region due to the unassociated chains. Under thermal fluctuations and/or external loading, the number and locations of junction zones can change leading to “zipping” (lengthening, i.e., expansion of the junction zones) and “unzipping” (shortening, i.e., shrinkage of the junction zones). This gives rise to intriguing features in biopolymer gels such as healing and damage-like energy dissipation. Despite the recognition of zipping and unzipping in such gels, the development of mathematical models that incorporate the microscopic mechanisms into the material’s macroscopic mechanical properties is still in its early stages. In this paper, we provide a systematic framework for such multiscale modeling. Several critical steps are taken to equip the eight-chain network model with a previously developed micromechanics model for a coil-rod structure, where the coil represents an unassociated chain and the rod represents a junction zone. Most importantly, for a network of coil-rod structures under zero stress, the rigidity induced by the rod leads to an end-to-end distance ( r 0 ) for the coil-rod which is different from a classical result for a Gaussian coil: n b where b is the Kuhn length and n is the number of Kuhn segments in the coil. By relaxing the incompressible assumption in the original eight-chain model, r 0 is determined for the gel network, which depends on the length of the junction zone. Consequently, as the junction zone extends/shrinks following zipping/unzipping under an external load, an irreversible deformation can occur after unloading, consistent with experimentally observed “permanent set”. The extension/shrinkage of the junction zone is captured by statistical mechanics analysis in the grand canonical ensemble, which allows the exchange of segments between the coil and the rod, driven by the binding energy of polymer chain association. The model also includes explicit consideration of swelling and the influence of solvent molecules as a result of their mixing with the polymer chains in the gel network. With physically reasonable parameters, the proposed model is shown to provide good matching with experimental data on the uniaxial testing of alginate gels, revealing progressive unzipping during loading and partial re-zipping during unloading leading to the appearance of a permanent set. This formulation not only paves the way for more advanced studies of disordered biopolymer gels but also lays the groundwork for modeling hybrid gels that contain coil-rod structures as a component.

无序生物聚合物凝胶，如由多糖和明胶合成的，在生物医学应用中发挥着重要作用，特别是在组织工程中。在这些凝胶的凝胶化过程中，聚合物链在胶凝剂的存在下结合，形成被称为结区的物理交联。与类似橡胶的网络相反，所得到的网络包括两个主要区域:由于结区而形成的有序区域和由于非相关链而形成的无定形区域。在热波动和/或外部载荷的作用下，结带的数量和位置可能发生变化，导致"压缩"(延长，即结带的扩大)和"解压缩"(缩短，即结带的收缩)。这在生物聚合物凝胶中产生了有趣的特性，如愈合和损伤样能量耗散。尽管人们已经认识到这种凝胶中的拉链和解拉链，但将微观机制纳入材料宏观力学特性的数学模型的发展仍处于早期阶段。在本文中，我们为这种多尺度建模提供了一个系统框架。为了将八链网络模型与先前开发的线圈-杆结构的微观力学模型相结合，研究人员采取了几个关键步骤，其中线圈代表非相关链，杆代表连接区。最重要的是，对于零应力下的线圈-棒结构网络，由棒引起的刚度导致线圈-棒的端到端距离(r 0)，这与高斯线圈的经典结果不同:n b，其中b是库恩长度，n是线圈中的库恩段数。通过放宽原始八链模型中的不可压缩假设，确定了凝胶网络的r0，它取决于结区的长度。因此，在外部载荷作用下，随着拉合/解合，结区扩展/收缩，卸载后会发生不可逆变形，与实验观察到的“永久集”一致。在大正则系综中，统计力学分析捕获了结区的扩展/收缩，这允许线圈和棒之间的片段交换，由聚合物链结合的结合能驱动。该模型还包括明确考虑溶胀和溶剂分子的影响，因为它们与凝胶网络中的聚合物链混合。在物理参数合理的情况下，该模型与海藻酸盐凝胶单轴试验数据吻合良好，加载过程中逐渐解压缩，卸载过程中部分重新压缩压缩，形成永久集。该配方不仅为无序生物聚合物凝胶的更高级研究铺平了道路，而且为包含线圈杆结构的混合凝胶建模奠定了基础。

Mechanics of Materials

A 3D finite strain constitutive model for shape memory polymers combined viscoelasticity and storage strain

Jiajun Chen, Chen Du, Qinghu Wang, Xiongqi Peng

doi:10.1016/j.mechmat.2024.105103

粘弹性与存储应变相结合的形状记忆聚合物三维有限应变本构模型

A 3D finite strain constitutive model combined viscoelasticity and storage strain for shape memory polymers (SMPs) is proposed. SMPs are phenomenally regarded as a homogeneous material of the viscoelastic glassy phase and hyperelastic rubbery phase in this model. Based on energy decomposition, the constitutive equation is derived using Clausius inequality and unified Helmholtz free energy. Then, an analytical expression for storage strain is presented, significantly simplifying the prediction of shape memory recovery process. The model is implemented in MATLAB and the commercial finite element software package ABAQUS using the UMAT subroutine. Our additional DMA tests and experimental data from the literature for various SMPs with different shape structures are used to verify the proposed model. All simulation results demonstrate the effectiveness of the proposed model in predicting the shape memory effect and complex thermomechanical behaviors of various SMPs.

提出了一种结合粘弹性和存储应变的形状记忆聚合物三维有限应变本构模型。在该模型中，SMPs被看作粘弹性玻璃相和超弹性橡胶相的均匀材料。在能量分解的基础上，利用克劳修斯不等式和统一亥姆霍兹自由能导出了本构方程。然后，提出了存储应变的解析表达式，大大简化了形状记忆恢复过程的预测。利用UMAT子程序在MATLAB和商用有限元软件包ABAQUS中实现了该模型。我们对不同形状结构的各种smp进行了额外的DMA测试和文献中的实验数据，以验证所提出的模型。所有的仿真结果都证明了该模型在预测各种smp的形状记忆效应和复杂的热力学行为方面的有效性。

Thin-Walled Structures

Process planning for laser peen forming of complex geometry: An analytical-based inverse study

Jiancheng Jiang, Zhi Li, Yi Zhang, Siyuan Chen, Yongxiang Hu

doi:10.1016/j.tws.2024.112274

复杂几何形状激光喷丸成形工艺规划:基于解析的逆向研究

Laser peen forming (LPF) is a promising process for the flexible manufacturing of complex thin-walled structures. However, process planning for LPF remains challenging due to the deformed geometry relying on the cumulative effect of thousands of laser shocks without dies. The optimization-based planning method is adaptable but easily gets trapped in local optima, leading to insufficient robustness and efficiency. To overcome these limitations, this study introduces an analytical-based inverse study to complement the optimization-based method. Firstly, an inherent and straightforward analytical model between eigen-moment and surface curvature is proposed, enabling a direct inverse determination of the eigen-moment field from the desired geometry shape. Subsequently, a clustering method is employed to achieve aggregation control over the analytically determined eigen-moment field, avoiding extensive optimization iterations. Moreover, a physical-based surface decomposition method is devised to formulate double-side LPF strategies for surfaces with negative or zero Gaussian curvature. To validate the proposed analytical-based process planning method, an elliptic paraboloid-like surface and a hyperbolic paraboloid surface are selected as the objectives. Experimental results show high conformity between the deformed and objective surfaces, validating the proposed method. The analytical-based planning method facilitates the efficient and robust determination of forming strategies, complementing the optimization-based method and providing a comprehensive solution for LPF process planning under small deformations.

激光喷丸成形(LPF)是一种很有前途的复杂薄壁结构柔性制造方法。然而，由于几何变形依赖于数千次无模具激光冲击的累积效应，LPF的工艺规划仍然具有挑战性。基于优化的规划方法适应性强，但容易陷入局部最优，鲁棒性和效率不足。为了克服这些局限性，本研究引入了一种基于分析的逆研究来补充基于优化的方法。首先，提出了本征矩与曲面曲率之间固有且直观的解析模型，实现了从所需几何形状直接反演本征矩场。随后，采用聚类方法实现对解析确定的特征矩场的聚集控制，避免了大量的优化迭代。此外，设计了一种基于物理的曲面分解方法，对高斯曲率为负或为零的曲面制定了双面LPF策略。为了验证所提出的基于解析的工艺规划方法，选择了一个椭圆抛物面和一个双曲抛物面作为目标曲面。实验结果表明，变形曲面与目标曲面高度吻合，验证了该方法的有效性。基于分析的规划方法有助于高效、稳健地确定成形策略，与基于优化的方法相辅相成，为小变形下的LPF工艺规划提供了全面的解决方案。

Post-fire bond-slip performance of concrete-filled stainless steel tube columns

Kang He, Yu Chen, Jiajun Tang, Xin Li

doi:10.1016/j.tws.2024.112275

不锈钢管混凝土柱火灾后粘结滑移性能研究

Concrete-filled stainless steel tube (CFSST) structures exhibit superior strength, durability, and fire resistance. These attributes, coupled with their aesthetic appeal and corrosion resistance, make them highly suitable for a broad range of civil engineering applications, ensuring long-term performance and safety across diverse environments. This study investigates the post-fire bond-slip performance of CFSST structures to facilitate the strengthening and retrofitting of fire-damaged CFSST structures. The paper reviews the bond-slip performance and fire resistance of CFSST. A series of fire tests and push-out tests were conducted on 99 circular CFSST stub columns, considering variables such as fire duration, wall thickness of the stainless steel tube, and concrete strength. The analysis covers the slip mechanism, load-slip relationship, sliding load, ultimate displacement, and ultimate bond strength of specimens post-fire. The bonding force between interfaces transitions from cementation to mechanical interlock and ultimately to friction, with some overlap among these mechanisms. A positive correlation exists between sliding load and wall thickness when fire duration is short. For shorter fire durations, fire exposure reduces the ultimate displacement while increasing bond-slip stiffness. Finally, a formula is proposed to predict the ultimate bond strength of CFSST stub columns following exposure to ISO 834 standard fire conditions.

混凝土填充不锈钢管(CFSST)结构表现出优异的强度，耐久性和耐火性。这些特性，再加上它们的美观性和耐腐蚀性，使它们非常适合广泛的土木工程应用，确保在各种环境下的长期性能和安全性。本研究旨在研究火灾后CFSST结构的粘结滑移性能，为火灾后CFSST结构的加固和改造提供依据。本文综述了CFSST的粘结滑移性能和耐火性能。考虑火灾持续时间、不锈钢管壁厚、混凝土强度等因素，对99根圆形CFSST短柱进行了一系列的防火试验和推出试验。分析了火灾后试件的滑移机理、荷载-滑移关系、滑动荷载、极限位移和极限粘结强度。界面之间的结合力从胶结转变为机械联锁，最终转变为摩擦，这些机制之间存在一些重叠。当火灾持续时间较短时，墙体厚度与滑动荷载之间存在正相关关系。对于较短的火灾持续时间，火灾暴露减少了极限位移，同时增加了粘结滑移刚度。最后，提出了CFSST短柱暴露于ISO 834标准火灾条件下的极限粘结强度预测公式。

Tests, simulations and web crippling design of S690 and S960 high strength steel unlipped channel sections under end-one-flange loading

Xiaoyi Lan, Xian-Wei Xu, Ou Zhao

doi:10.1016/j.tws.2024.112276

S690和S960高强度钢无唇槽钢端部单翼载荷试验、模拟及腹板破坏设计

This paper presents experimental and numerical investigations into the web crippling behaviour and structural design of high strength steel unlipped channel sections under end-one-flange loading. An experimental programme including six grade S690 and four grade S960 steel test specimens was firstly carried out, and the corresponding test set-up, procedures and results were reported. The web crippling test results were subsequently used in a finite element programme to validate developed finite element models, which were then adopted to perform parametric studies to cover wider parameter ranges of the bearing length, web slenderness and inside bend radius. Considering that relevant codified design provisions are absent, the design rules of normal strength steel unlipped channel sections, as prescribed in EN 1993-1-3, EN 1993-1-5 and AISI S100, were assessed for their suitability to high strength steel unlipped channel sections. It is found that the ultimate web crippling strength of high strength steel unlipped channel sections increases with increasing bearing length but decreasing web slenderness and inside bend radius. The codified design methods provide inaccurate and scattered resistance predictions for high strength steel unlipped channel sections under end-one-flange loading. Thus, an improved AISI S100 design method and a novel slenderness-based design method were proposed, which can outperform the codified design methods.

本文对高强度无唇槽钢在端部单翼荷载作用下的腹板破坏行为及结构设计进行了试验和数值研究。首先进行了包括6个S690级和4个S960级钢试件的试验方案，并报告了相应的试验装置、步骤和结果。腹板损伤试验结果随后用于有限元程序，以验证开发的有限元模型，然后采用该模型进行参数研究，以涵盖更广泛的轴承长度、腹板长细度和内弯曲半径参数范围。考虑到相关设计规范的缺失，对EN 1993-1-3、EN 1993-1-5和AISI S100中规定的标准强度钢非开口槽体截面设计规则对高强度钢非开口槽体截面的适用性进行了评估。研究发现，高强钢无唇沟道断面的腹板极限破坏强度随承载长度的增加而增大，而腹板长细比和内弯半径的减小而减小。规范的设计方法对高强度钢无唇槽钢在端部单翼荷载作用下的阻力预测不准确且分散。在此基础上，提出了一种改进的AISI S100设计方法和一种新的基于细长度的设计方法。