【新文速递】2023年10月31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，International Journal of Plasticity 1 篇，Thin-Walled Structures 4 篇

International Journal of Solids and Structures

Density-graded Voronoi honeycombs – A local transversely isotropic description

Ding Yuanyuan, Wang Shilong, Sun Zhengping, Shim V.P.W.

doi:10.1016/j.ijsolstr.2023.112555

密度分级的沃罗诺蜂窝--局部横向各向同性描述

Density-graded cellular materials, in which their relative density varies with location, are amenable to design for multi-functions, and have been used in mechanical buffers and protective structures. To estimate the force–deformation responses of density-graded cellular materials efficiently without resorting to modelling individual cells, a constitutive model based on local transverse isotropy is adopted. Metallic Voronoi honeycomb-like specimens with cell sizes that vary with position, are fabricated via 3D printing, to represent a density-graded cellular material with local transverse isotropy that varies with position. From quasi-static compression tests and cell-based finite element (FE) simulations, the influence of relative density on the continuum constitutive model is investigated and demonstrated to be significant. The model is then used to predict the global stress–strain response and deformation of cellular materials with positive and negative density-gradients, defined along the loading direction, subjected to uniaxial quasi-static compression, quasi-static indentation, and dynamic compression. The results show that for quasi-static compression, severe plastic deformation progresses from the low relative density region to the high relative density region; however, impact loading and indentation of negative density-gradient Voronoi honeycombs generates two zones of gross deformation – in the vicinity of the applied load and the opposite lower density end. Predictions based on the proposed constitutive model display good correlation with experimental and cell-based FE results.

密度分级细胞材料的相对密度随位置而变化，可用于多功能设计，已被用于机械缓冲器和保护结构。为了在不对单个细胞进行建模的情况下有效地估算密度分级蜂窝材料的力-变形响应，我们采用了基于局部横向各向同性的构成模型。我们通过三维打印技术制作了金属 Voronoi 蜂窝状试样，其细胞大小随位置而变化，以表示具有随位置变化的局部横向各向同性的密度分级蜂窝材料。通过准静态压缩试验和基于细胞的有限元（FE）模拟，研究并证明了相对密度对连续构成模型的重要影响。然后，利用该模型预测了沿加载方向定义的正负密度梯度的细胞材料在受到单轴准静态压缩、准静态压痕和动态压缩时的整体应力-应变响应和变形。结果表明，对于准静态压缩，严重的塑性变形会从低相对密度区域发展到高相对密度区域；然而，负密度梯度 Voronoi 蜂窝的冲击加载和压痕会产生两个严重变形区--施加载荷附近和相反的低密度端。根据所提出的构成模型进行的预测与实验和基于细胞的有限元分析结果显示出良好的相关性。

Journal of the Mechanics and Physics of Solids

A Snap-Through Instability of Cell Adhesion Under Perturbations in Hydrostatic Pressure

Liu Shaobao, Yang Haiqian, Xu Guang-Kui, Wu Jingbo, Tao Ru, Wang Meng, He Rongyan, Han Yulong, Genin Guy M., Lu Tian Jian, Xu Feng

doi:10.1016/j.jmps.2023.105476

静水压力扰动下细胞粘附的瞬时不稳定性

The balance between stress and adhesion governs many behaviors of adherent cells such as cell migration. In certain microenvironments such as that of a tumor, variations in hydrostatic pressure be substantial compared to cell-generated stresses. These variations can affect stress-activated ion channels whose activation can in turn affect cell volume and adhesion. To study these effects, we developed a theoretical model to relate changes in hydrostatic pressure to the morphology and volume of adherent cells. The model predicted the bistability of cell morphology (i.e., a snap-through instability) under hydrostatic pressure for certain ranges of adhesion energy density. This snap-through instability can enable cells to spontaneously detach from their environment, and may have bearing on migration and metastasis.

应力和粘附力之间的平衡制约着粘附细胞的许多行为，如细胞迁移。在肿瘤等某些微环境中，静水压的变化比细胞产生的应力大得多。这些变化会影响应力激活的离子通道，而离子通道的激活又会影响细胞体积和粘附性。为了研究这些影响，我们建立了一个理论模型，将静水压的变化与粘附细胞的形态和体积联系起来。该模型预测了在一定的粘附能量密度范围内，细胞形态在静水压力下的双稳态性（即速通不稳定性）。这种快穿不稳定性可使细胞自发地从环境中脱离，并可能对迁移和转移产生影响。

International Journal of Plasticity

Rate controlling deformation mechanisms in SS316L stainless steel manufactured using laser powder bed fusion technique

Jain Roopam, Yadava Manasij, Tripathi Aparna, Gurao N.P.

doi:10.1016/j.ijplas.2023.103787

利用激光粉末床熔融技术制造的 SS316L 不锈钢的速率控制变形机制

We conducted uniaxial tensile strain rate jump tests to account for the strain rate controlling mechanisms in the additively manufactured SS316L stainless steel. Special emphasis is placed on the role of high dislocation density and chemical segregation on dictating the rate sensitive behaviour. Lowest strain rate sensitivity is found, despite the highest dislocation density in the as build state, which signified the role of solute segregation at cell walls in increasing the activation volume and forms the strong basis for rejecting dislocation forest as the strain rate controlling obstacles. Consistent increase in the strain rate sensitivity with annealing is found consistent with the chemical homogenisation of the solutes causing smaller inter-obstacle spacing causing decreasing activation volume. Experimental findings are supported by CALPHAD simulations and mechanical threshold stress (MTS) modelling framework. Significant difference between the instantaneous and steady state rate sensitivity is understood using the dynamic pileup dislocation density readjustment mechanism causing considerable flow transient while adjusting the mobile dislocation density on strain rate change in the presence of solute decorated dislocation cells. Present investigation helps in gaining newer insights into the deformation mechanisms of the additively manufactured alloys featuring cellular microstructures.

我们进行了单轴拉伸应变速率跃变试验，以解释添加制造的 SS316L 不锈钢中的应变速率控制机制。我们特别强调了高位错密度和化学偏析在决定应变速率敏感性方面的作用。尽管在成型状态下位错密度最高，但应变速率灵敏度却最低，这表明细胞壁上的溶质偏析在增加活化体积方面发挥了作用，并为否定位错林作为应变速率控制障碍提供了有力依据。应变速率敏感性随退火的增加而增加，这与溶质的化学均匀化导致障碍物间距变小、活化体积减小是一致的。CALPHAD 模拟和机械阈值应力（MTS）建模框架为实验结果提供了支持。利用动态堆积位错密度再调整机制，可以理解瞬时速率敏感性和稳态速率敏感性之间的显著差异，这种机制在溶质装饰位错单元存在的应变速率变化时调整移动位错密度，从而造成相当大的流动瞬态。目前的研究有助于深入了解以蜂窝状微结构为特征的添加制造合金的变形机制。

Thin-Walled Structures

A novel sandwich structured spoof surface plasmon polaritons antenna integrating multibeam and enhanced mechanical performances

Dong Jiachen, Zheng Xitao, Han Yajuan, Huang Ruilin, Ji Zhengjiang, Cheng Linhao, Fu Xinmin, Yan Leilei

doi:10.1016/j.tws.2023.111306

集多波束和增强机械性能于一体的新型三明治结构欺骗性表面等离子体极化子天线

The conventional antennas will increase the radar cross section of aircrafts and affect their aerodynamic performances, a novel antenna scheme for radiation and load-bearing integrated design based on composite sandwich structure is proposed. By constructing spoof surface plasmon polaritons (SSPPs) structure and combining it with glass fiber composite (FR-4) plates, the radiation direction of the monopole can be controlled and the antenna will be endowed with load-bearing capacity. At the meantime, polymethacrylimide (PMI) foam is filled in its spacing to improve the mechanical performances greatly. Through electromagnetic (EM) simulation and test, it is found that four-beam radiation in different directions radiation and eight-beam can be realized by changing the position of the FR-4 laminates, and the bandwidth is all about 1 GHz with a peak gain about 6.5 dBi. Out-of-plane compression experiment indicates that the proposed PMI foam-filled multibeam antenna structure (PFMAS) gathers the high bearing capacity of multibeam antenna structure (MAS) and the high energy absorption characteristics of PMI foam, showing an obvious coupling effect. Its specific compressive strength is 150.10% and 6.28%, and energy absorption capacity per unit volume is 169.91% and 362.08% higher than that of PMI foam and MAS, respectively. The proposed PFMAS improves the structural utilization efficiency, and can be applied to some interlocking units of square honeycomb structure to endow multibeam radiation characteristics, which can expand the application of integrated antenna structures effectively.

传统天线会增加飞机的雷达截面，影响飞机的气动性能，因此提出了一种基于复合材料夹层结构的辐射与承重一体化设计的新型天线方案。通过构建欺骗性表面等离子体极化子（SSPPs）结构并将其与玻璃纤维复合材料（FR-4）板相结合，可以控制单极子的辐射方向，并使天线具有承载能力。同时，在其间距内填充聚甲基丙烯酰亚胺（PMI）泡沫，以大大提高机械性能。通过电磁（EM）仿真和测试发现，通过改变 FR-4 薄片的位置，可实现不同方向辐射的四波束辐射和八波束辐射，带宽均在 1 GHz 左右，峰值增益约为 6.5 dBi。面外压缩实验表明，所提出的聚甲基丙烯酸甲酯泡沫填充多波束天线结构（PFMAS）集 合了多波束天线结构（MAS）的高承载能力和聚甲基丙烯酸甲酯泡沫的高能量吸收特性，耦合效果明显。其比抗压强度和单位体积能量吸收能力分别比 PMI 泡沫和 MAS 高出 150.10% 和 6.28%，单位体积能量吸收能力和单位体积能量吸收能力分别比 PMI 泡沫和 MAS 高出 169.91% 和 362.08%。所提出的 PFMAS 提高了结构的利用效率，可应用于方形蜂窝结构的某些联锁单元，赋予其多波束辐射特性，从而有效拓展集成天线结构的应用。

Study on structural response of water-back plate under the combined action of shock wave and bubble loads generated by cylindrical charge in deep-water environment

Ma Teng, Wang Jinxiang, Liu Liangtao, Li Heng, Tang Kui, Gu Yangchen, Zhang Yifan

doi:10.1016/j.tws.2023.111307

深水环境中圆柱形装药产生的冲击波和气泡载荷共同作用下的背水板结构响应研究

The structural response of the water-back plate under the combined action of shock wave and bubble loads at water depths of 1–300 m is investigated numerically using an arbitrary Lagrange–Euler method. The accuracy of the numerical model is verified by a comparison with the shallow-water experimental results and theoretical results. Specifically, the influences of the water depth and length-to-diameter ratio of the cylindrical charge on the combined damage effect of the shock wave and bubble loads are analysed. The following conclusions are drawn. As water depth increases from 1m to 300m, the plastic deformation energy of the water-back plate decreases, meanwhile the permanent deformation mode of a water-backed plate changes from convex to concave under the combined action of shock wave and bubble loads; when the charge has large length-to-diameter, the plastic deformation energy of radial plate under combined action of the shock wave and bubble loads is higher than that of axial plate at water depths of 1–300 m, and both difference decrease with increasing water depth; the combined damage effect of the shock wave and bubble loads can be enhanced in the radial direction by increasing the length-to-diameter ratio in deep-water environments. When the length-to-diameter ratio increases from 1:1 to 8.2:1, the plastic deformation energy of the radial plate gradually increases by 7.58% from 10.68–11.49 J.

采用任意拉格朗日-欧拉方法，对水深 1-300 米处背水板在冲击波和气泡载荷共同作用下的结构响应进行了数值研究。通过与浅水实验结果和理论结果的比较，验证了数值模型的准确性。具体而言，分析了水深和圆柱形装料的长径比对冲击波和气泡载荷的综合破坏效应的影响。得出以下结论。当水深从 1 米增加到 300 米时，背水板的塑性变形能量减小，同时在冲击波和气泡载荷的共同作用下，背水板的永久变形模式由凸变为凹；当装药的长径比较大时，在水深 1-300 米处，径向板在冲击波和气泡载荷联合作用下的塑性变形能高于轴向板，且两者的差值随水深的增加而减小；在深水环境中，通过增大长径比，可增强径向冲击波和气泡载荷的联合破坏效应。当长径比从 1:1 增加到 8.2:1 时，径向板的塑性变形能从 10.68-11.49 J 逐渐增加了 7.58%。

A Spatial Stability Theory of Thin-walled Steel Beams Pre-stressed by Spatially Inclined Un-bonded Cables and its FE Formulation

Mehdi Agha Intizar, Zhang Fengping, Kim Moon-Young

doi:10.1016/j.tws.2023.111308

空间倾斜无粘结索预应力薄壁钢梁的空间稳定性理论及其有限元计算公式

A spatial stability theory of mono-symmetric thin-walled steel beams pre-stressed (PS) by spatially inclined cables is firstly derived using an energy method where it is assumed that deviators are rigid. Its FE formulation is then presented under bonded/un-bonded multi-deviator conditions. After that, validity and accuracy of the present formulation is demonstrated through numerical examples. Finally, effects of initial tension, deviator numbers, inclined cable profiles, and un-bonded/bonded conditions on lateral-torsional buckling (LTB) of the PS bi-/mono-symmetric beams are investigated under external loadings. Particularly, new findings on LTB characteristics of the PS beams are presented with a specific emphasis on the effects of increasing initial tension.

首先使用能量法推导了空间倾斜钢索预应力（PS）单对称薄壁钢梁的空间稳定性理论，其中假定偏差是刚性的。然后，在有粘结/无粘结多偏差器条件下对其进行了有限元计算。之后，通过数值示例证明了本公式的有效性和准确性。最后，研究了在外部荷载作用下，初始拉力、偏差数、斜拉索剖面和无粘结/粘结条件对 PS 双/单对称梁侧向扭转屈曲（LTB）的影响。特别介绍了 PS 梁 LTB 特性方面的新发现，重点强调了增加初始拉力的影响。

Structural behaviour of cold-formed steel elliptical hollow section stub columns after exposure to ISO-834 fire curve

Zuo Wenkang, Chen Man-Tai, Young Ben

doi:10.1016/j.tws.2023.111309

冷弯钢椭圆空心截面桩柱暴露于 ISO-834 防火曲线后的结构行为

The present study undertakes the post-fire stub column behaviour of cold-formed steel elliptical hollow sections (CFS-EHS) by experimental and numerical analyses. A total of 18 CFS-EHS stub column specimens made up of four cross-section series was firstly prepared, heated in a gas furnace as per the ISO-834 standard fire and then naturally cooled down to ambient temperature. Four fire exposure temperatures of 300°C, 550°C, 750°C and 900°C were adopted. Details of the experimental campaign, e.g., specimen preparation, test procedures and results, are presented. Accurate finite element (FE) model was established to mimic the experimental responses from various perspectives. Exhaustive parametric studies were subsequently conducted on 224 post-fire CFS-EHS stub columns to generate substantial data. The test and FE results were compared with the strength calculations using the equivalent diameter method and equivalent rectangular hollow section method developed for hot-finished steel elliptical hollow sections without fire exposure, the Direct Strength Method (DSM) stipulated in the American Specification AISI S100, as well as the modified DSM previously calibrated for CFS-EHS without fire exposure. By replacing the material properties obtained at ambient temperature with the post-fire material properties in the aforementioned design methods, it is shown that the equivalent section methods and the existing DSM overly underestimate the column strengths, whilst the modified DSM yields precise and reliable strength estimations. It is recommended to adopt the modified DSM for calculating the residual compressive strengths of CFS-EHS stub columns after exposure to the ISO-834 standard fire.

本研究通过实验和数值分析研究了冷弯型钢椭圆空心截面（CFS-EHS）在火灾后的残柱行为。首先制备了由四个截面系列组成的 18 个 CFS-EHS 存根柱试样，按照 ISO-834 标准在燃气炉中加热，然后自然冷却至环境温度。采用了 300°C、550°C、750°C 和 900°C 四种火曝温度。本文介绍了实验活动的细节，如试样制备、测试程序和结果。建立了精确的有限元（FE）模型，以便从各个角度模拟实验反应。随后对 224 根火灾后 CFS-EHS 存根柱进行了详尽的参数研究，以获得大量数据。测试和 FE 结果与使用等效直径法和等效矩形空心截面法进行的强度计算结果进行了比较，等效直径法和等效矩形空心截面法是针对无火灾暴露的热轧钢椭圆空心截面而开发的，DSM 是美国规范 AISI S100 中规定的直接强度法（DSM），而修改后的 DSM 之前已针对无火灾暴露的 CFS-EHS 进行过校准。通过将上述设计方法中在环境温度下获得的材料特性替换为火灾后的材料特性，可以看出等效截面法和现有的 DSM 低估了柱子的强度，而修改后的 DSM 则能获得精确可靠的强度估算。建议采用修改后的 DSM 计算 CFS-EHS 存根柱在 ISO-834 标准火灾后的残余抗压强度。