【新文速递】2024年2月21日固体力学SCI期刊最新文章

 

今日更新：Journal of the Mechanics and Physics of Solids 1 篇，Thin-Walled Structures 8 篇

Journal of the Mechanics and Physics of Solids

Fluid-injection control on energy partitioning during the earthquake cycle

Maryam Alghannam, Hector Gomez, Ruben Juanes

doi:10.1016/j.jmps.2024.105580

注入流体对地震周期中能量分配的控制

During an earthquake, the elastic energy stored in the Earth is released as frictional energy and radiated energy in the form of seismic waves. The partitioning of energy released during an earthquake gives an indication of the overall size of the earthquake and its potential for damage to man-made structures. Here, we perform an energy analysis of fluid-injection-induced earthquakes using a single-degree-of-freedom spring poroslider and rate-and-state friction. We show that seismic radiation can be modeled within the single-degree-of-freedom spring-slider by adding a radiation damping term. We then use it to study fluid injection and assess its effects on the energy partitioning during induced and triggered earthquakes. We find that: (1) seismic efficiency, stress drop, and total slip are directly influenced by the rate of increase in pore pressure, (2) the ratio of elastic energy stored in the skeleton to injection energy is low and is influenced by the rate of fluid injection, (3) seismic injection efficiency is also low and is lower for induced earthquakes compared to triggered ones, and (4) fluid injection leads to bigger and potentially more damaging earthquakes overall.

地震时，地球中储存的弹性能量会以摩擦能和地震波的形式释放出来。地震过程中释放的能量分区可显示地震的总体规模及其对人造结构造成破坏的可能性。在此，我们使用单自由度弹簧孔滑块和速率与状态摩擦对注入流体引发的地震进行了能量分析。我们证明，地震辐射可以通过添加辐射阻尼项在单自由度弹簧滑块中建模。然后，我们用它来研究流体注入，并评估其对诱发地震和触发地震期间能量分配的影响。我们发现(1) 地震效率、应力下降和总滑移直接受孔隙压力增加速率的影响；(2) 骨架中存储的弹性能量与注入能量的比率较低，且受流体注入速率的影响；(3) 地震注入效率也较低，且诱发地震的注入效率低于触发地震；(4) 流体注入会导致更大、潜在破坏性更强的地震。

Thin-Walled Structures

Dynamic stiffness method and CUF-based component-wise theories applied to free vibration analysis of solid beams, thin-walled structures and reinforced panels

Xiao Liu, Alfonso Pagani, Erasmo Carrera, Xiang Liu

doi:10.1016/j.tws.2024.111707

应用于实心梁、薄壁结构和加固板自由振动分析的动态刚度法和基于 CUF 的分量-分项理论

In this paper, an exact dynamic stiffness formulation using higher-order theories with displacement variables only is presented and subsequently used to investigate the free vibration characteristics of solid beams, thin-walled structures and reinforced panel structures. In essence, higher-order displacement fields are developed by using the Carrera unified formulation (CUF), and by discretizing the cross-section kinematics with bilinear, cubic and fourth-order Lagrange polynomials. In particular, the component-wise (CW) approach based on Lagrange expansion is applied in which the solid part and thin-walled part are considered as two independent components that can be assembled. The principle of virtual displacements is used to derive the governing differential equations and the associated natural boundary conditions. An exact dynamic stiffness matrix is then developed by relating the amplitudes of harmonically varying loads to those of the responses. The explicit terms of the dynamic stiffness matrices are also presented. The Wittrick–Williams algorithm of the dynamic stiffness method (DSM) is applied with the explicit expressions of the J0 count for beam elements under all above support conditions. In return, there is no need to refine the element in the DSM, and thus, it becomes immensely efficient. The accuracy and efficiency of the proposed methodology are extensively assessed for different solid beams, thin-walled structures and reinforced panels and the results are compared with those appearing in published literature and also checked by 3D finite element (FE) solutions.

本文提出了一种仅使用位移变量的高阶理论的精确动态刚度公式，并随后用于研究实心梁、薄壁结构和加固板结构的自由振动特性。从本质上讲，高阶位移场是通过使用卡雷拉统一公式（CUF）以及使用双线性、三次方和四阶拉格朗日多项式对横截面运动学进行离散化而形成的。特别是采用了基于拉格朗日展开的分量法（CW），将实心部分和薄壁部分视为两个可组装的独立分量。虚拟位移原理用于推导控制微分方程和相关的自然边界条件。然后，通过将谐波变化载荷的振幅与响应的振幅联系起来，得出精确的动态刚度矩阵。动态刚度矩阵的显式项也一并列出。动态刚度法（DSM）的 Wittrick-Williams 算法与上述所有支撑条件下梁元素的 J0 数值的明确表达式一起应用。反过来，在 DSM 中不需要对元素进行细化，因此变得非常高效。针对不同的实心梁、薄壁结构和加固板，对所建议方法的准确性和效率进行了广泛评估，并将结果与已发表文献中的结果进行了比较，同时还通过三维有限元 (FE) 解决方案进行了检验。

Mechanical response of a novel square dome shell with bistable behavior: improved analytical method and empirical model

Zhuangzhuang Li, Xuelin Li, Zhuoyu Guo, Yue Zhou, Jiahui Lin, Zonglai Mo, Jun Li

doi:10.1016/j.tws.2024.111722

具有双稳态行为的新型方形穹顶壳的机械响应：改进的分析方法和经验模型

In this study, a novel square dome-shaped shell with a fascinating bistable behavior is proposed, which is able to quickly switch to a new stable configuration within its elastic range under a certain load, due to its elastic instability. Compared to most circular shells currently studied, it is easier to arrange multiple structures in three-dimensional space to obtain multistable responses. Numerical and experimental methods were adopted for the study of the mechanical response of the square shell, and main influence parameters were also investigated. In addition, an improved piecewise fitting method is introduced to establish an empirical formula for predicting the mechanical response of bistable shells, which can be used to guide the design of bistable shells. Finally, two types of metamaterials, uniaxial compressible metamaterials and triaxial compressible metamaterials, are successfully designed according to the above theory, the typical behaviors of which are studied via simulations. This novel structure presented in this paper has broad application prospects in the fields of energy absorption and programmable deformation structures.

本研究提出了一种具有迷人双稳态行为的新型方形穹顶壳，由于其弹性不稳定性，在一定载荷作用下，能够在弹性范围内快速切换到新的稳定构型。与目前研究的大多数圆壳相比，它更容易在三维空间中排列多个结构，从而获得多稳响应。采用数值和实验方法研究了方壳的力学响应，并对主要影响参数进行了研究。此外，还引入了一种改进的分片拟合方法，建立了预测双稳态壳力学响应的经验公式，可用于指导双稳态壳的设计。最后，根据上述理论成功设计了两种超材料，即单轴可压缩超材料和三轴可压缩超材料，并通过仿真研究了其典型行为。本文介绍的这种新型结构在能量吸收和可编程变形结构领域具有广阔的应用前景。

Design of Cold-Formed Z-shaped purlin-to-rafter connections subject to pull-through failure

Haripriya Karthikeyan, Bishal Naik, Mahendrakumar Madhavan

doi:10.1016/j.tws.2024.111725

受拉穿失效影响的冷成型 Z 形檩条与椽子连接设计

The current study is focused on understanding the pull-through behaviour of Z-Shaped Cold-Formed Steel (CFS) purlin-to-rafter connection. A total of forty tests were conducted using small-scale testing methods to investigate the influence of parameters such as thickness, depth, and flange width of the purlin section along with the size of the screw head diameter. The results indicated that the test specimens exhibited two modes of pull-through failure (i) rupture-type failure and (ii) bearing-type failure. A transition from rupture-type to bearing-type was observed with an increase in thickness from 1 mm to 3 mm. Both the failure modes were accompanied by tilting of the screw due to eccentricity in the applied load for Z-Shaped purlins. A full-field measurement approach called Three-Dimensional Digital Image Correlation (3D-DIC) technique was employed to better understand the failure mechanism. The DIC strain contours adequately captured the tilting of the screw that can be attributed to the increased strain and out-of-plane deformation at the vicinity of the screw head. A comparison of the test with existing design standards indicates that the design guidelines are unconservative for Z-shaped purlin sections. A modified design equation is proposed to determine the pull-through capacity of Z-shaped purlin-to-rafter connection. Further, reliability study was carried out to determine the resistance and safety factors for the preliminary design equations proposed.

当前研究的重点是了解 Z 形冷弯型钢（CFS）檩条与椽子连接的拉穿行为。研究人员使用小规模测试方法进行了总共 40 次测试，以研究檩条截面的厚度、深度和翼缘板宽度等参数以及螺钉头直径大小的影响。结果表明，试样表现出两种拉穿失效模式（i）断裂型失效和（ii）承载型失效。随着厚度从 1 毫米增加到 3 毫米，可观察到从断裂型向轴承型的过渡。对于 Z 形檩条来说，这两种失效模式都伴随着螺杆因外加载荷偏心而倾斜。为了更好地了解失效机理，我们采用了一种名为三维数字图像相关（3D-DIC）技术的全场测量方法。DIC 应变轮廓图充分捕捉到了螺杆的倾斜，这可归因于螺杆头部附近的应变增加和平面外变形。将测试结果与现有设计标准进行比较后发现，对于 Z 形檩条截面而言，设计准则并不严谨。我们提出了一个修改后的设计方程，以确定 Z 型檩条与椽子连接的抗拉能力。此外，还进行了可靠性研究，以确定初步设计方程的阻力和安全系数。

A two-direction cross-iteration solution for in-plane vibrations of thin-walled composite plates with a simplified explicit vibration mechanical model

Lin Zhao, Yuan Liu, Xibin Cao, Zhongxi Shao, Xuan Zhang, Qingyang Deng, Chenhao Sun

doi:10.1016/j.tws.2024.111728

用简化的显式振动力学模型解决薄壁复合板平面内振动的双向交叉迭代问题

For the fine and high reliability design of advanced precision engineering structures, this work presents an analytically cross-iteration method for in-plane vibrations analysis of thin-walled composite plates, the single-layer and laminated structures both involved. The governing equations and corresponding boundary conditions are derived adopting Rayleigh’s principle, in which the governing partial differential equations are transferred into ordinary differential equations. The most important advantage of this method lies in the fact that the explicit eigenvalue equations and mode functions are obtained with only a series of four-by-four matrices by simplifying boundary conditions in the two-direction cross-iteration procedures. Accuracy of the present method is verified by comparison with the previous studies and the finite element method in natural characteristics solutions, and convergence analysis on the single-layer orthotropic plates and composite laminates reveals the high efficiency and stability. Finally, the effects of boundary conditions, ply orientation angles, stacking sequences, aspect ratios and stiffness ratios on the in-plane natural characteristics are investigated. The extensive results presented in this work for the first time can be taken as the benchmarks data compared with other methods.

为实现先进精密工程结构的精细化和高可靠性设计，本研究提出了一种分析交叉迭代法，用于薄壁复合材料板的面内振动分析，包括单层结构和层状结构。利用雷利原理推导出控制方程和相应的边界条件，并将控制偏微分方程转换为常微分方程。该方法最重要的优点在于，通过简化双向交叉迭代程序中的边界条件，只需一系列四乘四矩阵即可获得显式特征值方程和模态函数。通过与前人的研究和自然特性求解中的有限元法进行比较，验证了本方法的准确性，对单层正交板和复合层压板的收敛分析表明了本方法的高效性和稳定性。最后，研究了边界条件、层间取向角、堆叠顺序、纵横比和刚度比对平面内自然特性的影响。本研究首次提出的大量结果可作为与其他方法比较的基准数据。

Experimental and numerical investigations of damage and ballistic limit velocity of CFRP laminates subject to harpoon impact

Wei Zhao, Zhaojun Pang, Mingxiao Wang, Peng Li, Zhonghua Du

doi:10.1016/j.tws.2024.111732

受鱼叉撞击的 CFRP 层压板损伤和弹道极限速度的实验和数值研究

The harpoon is a space debris capture mechanism with strong adaptability to targets. In this paper, experiments and finite element models are used to study the harpoon impact on carbon fiber laminate. Firstly, a harpoon penetration gas gun experiment was designed to obtain the damage and ballistic limit velocity of carbon fiber laminates. Then finite element modeling and numerical simulation of the impact on the laminate were carried out using the user-defined VUMAT subroutine in ABAQUS, focusing on the ballistic limit velocity change, damage evolution of the laminate and energy absorption of the laminate when the harpoon penetrates the laminate obliquely at a specific angle. The results showed that compared with vertical penetration, the ballistic limit velocity of harpoon increased by 3.2%, 9.6% and 24.3% respectively under 15°, 30° and 45° oblique penetration conditions; and with the increase of harpoon impact angle, the damage of laminates gradually tended to occur on one side of the projection of harpoon on laminates; while in terms of energy absorption, the energy absorption of laminates for the same angle tended to a constant value as the launch velocity increased.

鱼叉是一种空间碎片捕获装置，对目标具有很强的适应性。本文利用实验和有限元模型研究了鱼叉对碳纤维层压板的影响。首先，设计了鱼叉穿透气 枪实验，以获得碳纤维层压板的损伤和弹道极限速度。然后使用 ABAQUS 中用户自定义的 VUMAT 子程序对层压板的冲击进行有限元建模和数值模拟，重点研究了鱼叉以特定角度斜穿透层压板时，层压板的弹道极限速度变化、损伤演化和能量吸收。结果表明，与垂直穿透相比，在 15°、30° 和 45°斜穿透条件下，鱼叉的弹道极限速度分别增加了 3.2%、9.6% 和 24.3%；随着鱼叉撞击角度的增加，层压板的损伤逐渐趋向于鱼叉在层压板上投影的一侧；而在能量吸收方面，随着发射速度的增加，相同角度下层压板的能量吸收趋向于恒定值。

Multi-objective optimization design of a new non-uniform rectangular honeycomb sandwich panel

Xuanhe Luo, Gang Li, Zeng Meng

doi:10.1016/j.tws.2024.111729

新型非均匀矩形蜂窝夹芯板的多目标优化设计

Honeycomb sandwich panels have a wide range of applications in aerospace, marine and energy industry due to their high stiffness-to-weight ratio. In this study, a new non-uniform rectangular honeycomb core is presented to promote its material utilization ratio. The non-uniform wall of honeycomb core is described using Bezier curves, and the effective elastic constants are obtained by both the geometric equivalent method and the strain energy-based homogenization method. To analyze the bending and buckling behaviors of the sandwich panel, the parabolic shear deformation theory is adopted, and the governing equations are derived by employing Hamilton's principle. Then, the closed-form solutions of bending and buckling responses of the non-uniform rectangular honeycomb sandwich panel are derived. Furthermore, multi-objective design formulations are established, with the objectives of minimizing the weight and deflection, and maximizing the critical buckling load. Illustrative examples demonstrate that the non-uniform design of the honeycomb core can remarkably increase the material utilization rate and improve the mechanical performance of sandwich panels.

蜂窝夹芯板具有很高的刚重比，因此在航空航天、航海和能源行业有着广泛的应用。本研究提出了一种新型非均匀矩形蜂窝芯，以提高其材料利用率。利用贝塞尔曲线描述了蜂窝芯的非均匀壁，并通过几何等效法和基于应变能的均质化法获得了有效弹性常数。为了分析夹芯板的弯曲和屈曲行为，采用了抛物线剪切变形理论，并利用汉密尔顿原理推导了控制方程。然后，推导出了非均匀矩形蜂窝夹芯板弯曲和屈曲响应的闭式解。此外，还建立了以重量和挠度最小化以及临界屈曲载荷最大化为目标的多目标设计公式。示例表明，蜂窝芯的非均匀设计可显著提高材料利用率，改善夹芯板的机械性能。

A comparative study on failure mechanisms of open-hole and filled-hole composite laminates: Experiment and numerical simulation

Di Zhang, Jin Zhou, Jizhen Wang, Wenxin Zhang, Zhongwei Guan

doi:10.1016/j.tws.2024.111730

关于开孔和填充孔复合材料层压板失效机理的比较研究：实验与数值模拟

The strength of composites with open holes (OH) and filled holes (FH) is a critical factor in determining mechanical allowances for engineering design. This study employs both experimental and numerical analyses to investigate the mechanical behaviour of composite laminates subjected to open-hole tension (OHT) and open-hole compression (OHC), filled-hole tension (FHT) and filled-hole compression (FHC). A progressive damage model (PDM) has been developed to predict the load-carrying capacity of both OH and FH laminates, with deviations lower than 6 % in comparison to the corresponding experimental results. Results indicate that OHC/FHC laminates experience more pronounced damage compared to OHT/FHT laminates prior to the maximum load. Additionally, delamination in FHC laminates is significantly reduced compared to OHC laminates. In comparison to OHT/OHC laminates, the presence of a filled bolt increases the maximum load of FHT/FHC laminates by 10.8 % and 36.0 %, respectively, due to relieving the stress concentration near the hole. Moreover, a higher contact friction coefficient between the bolt and laminate leads to a higher maximum load, particularly for FHC laminates, as the increased friction effectively hinders the matrix crack propagation. These findings provide valuable insights for assisting the design of composite structures.

带有开孔（OH）和填充孔（FH）的复合材料的强度是确定工程设计机械余量的关键因素。本研究通过实验和数值分析来研究复合材料层压板在受到开孔拉伸（OHT）和开孔压缩（OHC）、填充孔拉伸（FHT）和填充孔压缩（FHC）作用时的机械性能。建立的渐进损伤模型（PDM）可预测 OHC 和 FHC 复合材料的承载能力，与相应的实验结果相比，偏差小于 6%。结果表明，与 OHT/FHT 层压板相比，OHC/FHC 层压板在最大载荷之前经历了更明显的损坏。此外，与 OHC 层压板相比，FHC 层压板的分层现象明显减少。与 OHT/OHC 层压板相比，填充螺栓的存在使 FHT/FHC 层压板的最大载荷分别增加了 10.8% 和 36.0%，这是由于孔附近的应力集中得到了缓解。此外，螺栓与层压板之间的接触摩擦系数越大，最大载荷就越大，尤其是对于 FHC 层压板，因为摩擦力的增加会有效阻碍基体裂纹的扩展。这些发现为复合材料结构的设计提供了宝贵的启示。

The competition between buckling and stress failure of degraded composite cylindrical shell under combined axial compression and external pressure loads

W.M. Mahdy, Linjuan Wang, Fengrui Liu, Libin Zhao

doi:10.1016/j.tws.2024.111731

轴向压缩和外部压力联合载荷下降解复合材料圆柱壳体屈曲与应力破坏之间的竞争

When thin-walled composite cylindrical shells are subjected to combined loads, not only will they buckle, but they could fail under overstressing. Buckling-failure and stress-failure are two types of failure that compete mutually, and if one of them occurs, the structure loses its ability to carry the load. However, there is a lack of study, and very little attention was paid to the competitive-failure of the composite cylindrical shells under combined loads. To bridge this research gap, a competitive failure analysis framework of degraded composite cylindrical shells exposed to combined axial compression and external pressure loads was developed, considering the nonlinear buckling-failure interacting curve approach for buckling-failure analysis and the Tsai-Wu failure criterion for stress-failure analysis. The material degradation model was adopted to modify the properties of the failed ply based on two degrading philosophies. The proposed framework agrees well with the published results. Extensive parametric studies are accomplished and presented to detect the failure mode of composites. For material parametric study, the variation of material properties does not significantly affect the shape of the normalized buckling-failure interacting curve, while it appreciably affects the behavior of the stress-failure interacting curve. Moreover, it is found that as the proportions of the longitudinal compressive strength to longitudinal modulus and transverse tensile strength to transverse modulus of composite materials increase, the tendency for buckling-failure increases; otherwise, stress-failure happens. For a geometric parametric study, decreasing the radius-to-thickness ratio leads to an increase in the shape of the buckling-failure interacting curve and the possibility of stress-failure.

当薄壁复合材料圆柱形壳体承受联合载荷时，不仅会发生屈曲，而且可能在过应力作用下失效。屈曲失效和应力失效是两种相互竞争的失效类型，如果其中一种失效发生，结构就会丧失承载能力。然而，目前对复合材料圆柱形壳体在组合载荷作用下的竞争失效还缺乏研究，关注度也很低。为了弥补这一研究空白，我们建立了承受轴向压缩和外部压力联合载荷的降解复合材料圆柱壳竞争失效分析框架，在屈曲失效分析中考虑了非线性屈曲失效交互曲线方法，在应力失效分析中考虑了蔡武失效准则。根据两种降解原理，采用材料降解模型来修改失效层的属性。所提出的框架与已公布的结果非常吻合。为检测复合材料的失效模式，完成并介绍了广泛的参数研究。在材料参数研究方面，材料特性的变化对归一化屈曲-失效交互曲线的形状没有显著影响，但对应力-失效交互曲线的行为有明显影响。此外，研究还发现，当复合材料的纵向抗压强度与纵向模量、横向抗拉强度与横向模量的比例增加时，屈曲失效的趋势也会增加；反之，则会发生应力失效。在几何参数研究中，减小半径与厚度之比会导致屈曲-失效交互曲线的形状和应力-失效的可能性增加。