Loading...

Table of Content

    30 October 2026, Volume 47 Issue 10
    On the mechanics of nonlocal lattices using a lattice Green’s function method
    Yuhao GONG, Jinxing LIU
    2026, 47(10):  2123-2144.  doi:10.1007/s10483-026-3434-8
    Abstract ( 5 )   HTML ( 2)   PDF (8883KB) ( 2 )  
    Figures and Tables | References | Related Articles | Metrics

    A lattice Green’s function (LGF) framework is proposed to investigate the mechanical properties of nonlocal lattices (NLLs) with periodically distributed dense defects. The novelty lies in extending the periodic LGF (PLGF) to beam lattices and reformulating both dense defects and nonlocal elements as periodic equivalent nodal forces on a perfect counterpart. This enables displacement perturbation, stress redistribution, and long-range interaction among different unit cells (UCs) to be captured without repeated finite element modeling. With the superposition principle, the defective NLL is transformed into its perfect counterpart, and the effective moduli are derived via strain-energy equivalence. The accuracy of the proposed PLGF method in predicting displacement fields and moduli is verified against the finite element method (FEM) results. The effects of nonlocal interactions on deformation, anisotropic moduli, defect toughening, and stress redistribution are analyzed, providing an efficient theoretical tool for designing toughened lattice metamaterials.

    Multi-field coupling characteristics of two-dimensional piezoelectric quasicrystals with an elliptical inclusion
    Tangrui LAI, Liangliang ZHANG, Yang LI, Xiang MU, Yang GAO
    2026, 47(10):  2145-2164.  doi:10.1007/s10483-026-3437-7
    Abstract ( 1 )   HTML ( 0)   PDF (5592KB) ( 0 )  
    Figures and Tables | References | Related Articles | Metrics

    With the rapidly increasing demand for strongly coupled multifunctional materials in engineering applications such as high-performance sensors, defect problems in piezoelectric quasicrystals (PQCs) have attracted growing attention. This study investigates the mechanical behavior of a two-dimensional (2D) PQC containing an elliptical inclusion subjected to uniform loading at infinity and a concentrated force applied in the matrix. Based on the Stroh formalism, combined with conformal mapping and analytic continuation techniques, the analytical solutions for the in-plane displacements and stresses are derived. Meanwhile, the correctness of the model is verified through a comparison between the degenerated infinite-plane numerical results and classical reference solutions. Numerical examples are further conducted to systematically analyze the influence of the inclusion geometry and the loading position on the multi-field coupling responses. The results show that the elliptical inclusion significantly alters the spatial distributions of the mechanical and electrical fields, producing strong disturbances near the inclusion boundary. In particular, decreasing the ellipse aspect ratio b/a markedly enhances the local coupling and stress concentration, whereas the circular inclusion exhibits the weakest anisotropy, resulting in relatively smooth field distributions and low stress concentration. These findings indicate that properly utilizing geometric defects can serve as an effective means of tuning multi-field coupling behavior, and this strategy should be fully considered in engineering design.

    Frequency splitting and vibration evaluation of braided composite toroidal-cylindrical shell with soft coating
    Jichuan CAO, Hui LI, Jintong HAN, Xinyu CUI, Haile YAN, Bo YANG, Zeng LIN, Feng ZHAO, Wei SUN, Bangchun WEN
    2026, 47(10):  2165-2186.  doi:10.1007/s10483-026-3439-9
    Abstract ( 2 )   HTML ( 0)   PDF (11255KB) ( 1 )  
    Figures and Tables | References | Related Articles | Metrics

    To facilitate the design of advanced aero-engine casings, a dynamic analysis framework is developed for the first time for the braided composite toroidal-cylindrical shell with soft coating (BCTCS-SC). The effective material parameters are first evaluated, after which high-order strain-displacement relations are established to describe the deformation of the coupled shell structure. The virtual spring method is adopted to model the rigid connection between the two infrastructures and the end constraints. The displacement fields are then approximated by doubly discrete spectral functions, and the governing dynamic equations are derived via the energy method. The proposed model is validated through comparative studies, and the corresponding mode shapes are visualized. Finally, the effects of key structural and material parameters on the natural characteristics, frequency splitting, and modal exchange are analyzed. The results further clarify the suppression effect of soft coating by modifying the equivalent stiffness and damping distribution. This study establishes a theoretical framework and a technical approach for frequency-splitting prediction and vibration-suppression design of coated braided composite coupled structures.

    Self-flipping mechanism of a bistable photoactuated liquid crystal elastomer-magnet beam
    Lin ZHOU, Bingyao REN, Haiming CHEN, Xuehui CHEN, Ting GAO, Kai LI
    2026, 47(10):  2187-2208.  doi:10.1007/s10483-026-3443-9
    Abstract ( 1 )   HTML ( 0)   PDF (4348KB) ( 0 )  
    Figures and Tables | References | Related Articles | Metrics

    Photoactuated self-oscillating systems have received increasing attention due to their capability to convert light energy into sustained mechanical motion. Nevertheless, most reported systems exhibit smooth and continuous oscillations, with limited ability to accumulate elastic energy and release it abruptly for burst-like motion. This study proposes a bistable photoactuated liquid crystal elastomer (LCE)-magnet beam composed of a bilayer composite beam, a tip magnet, and two metal blocks. Through the coupling of photothermal contraction and magnetic adhesion, the proposed beam exhibits the autonomous self-flipping behavior without external control. A nonlinear mechanical model is developed to clarify the underlying mechanism, showing that the self-flipping motion results from the competition between the equivalent force induced by LCE contraction and the magnetic adhesion forces from the two metal blocks. Three motion states, namely static, single-flip, and continuous self-flipping states, are identified. Two critical contraction conditions for state transitions are derived analytically, providing criteria for the onset and persistence of self-flipping oscillation. Parametric analysis further shows that key system parameters govern the transition boundaries between motion states and affect the oscillation frequency. The results provide useful insight into the design of photoactuated smart beam structures with self-sustained burst-like periodic motion.

APS Journals | CSTAM Journals | AMS Journals | EMS Journals | ASME Journals