http://yetl.yabesh.ir/yetl1/handle/yetl/19037 Mon, 14 Sep 2026 17:02:05 GMT 2026-09-14T17:02:05Z https://localhost:443/yetl1/bitstream/id/184271/ http://yetl.yabesh.ir/yetl1/handle/yetl/19037 http://yetl.yabesh.ir/yetl1/handle/yetl/4316086 Trouser Tearing Fracture Characteristics of the Metal Foam Sandwich Plate Yuan, Long; Bai, Jinwen; Wu, Xiwei; Luo, Xilin; Tian, Lei; Zhang, Jianxun Abstract. The unique deformation and energy absorption mechanisms of sandwich plates under trouser tearing conditions are not yet well understood. In this article, trouser tearing fracture characteristics of the metal foam sandwich plate under tensile loading are investigated by theoretical analysis and numerical simulations. An analytical model for trouser tearing fracture characteristics of the metal foam sandwich plate is established, considering foam compression, plastic bending deformation, unbending deformation, and tearing of the cracks. The finite element simulation of trouser tearing fracture characteristics of the metal foam sandwich plate is conducted to verify the theoretical model, showing good consistency between the numerical and analytical results. The effects of the trouser leg width, foam thickness, bending radius, and foam strength on trouser tearing fracture characteristics of the metal foam sandwich plate are discussed. The tearing load and energy absorption increase with the increase of trouser leg width, foam thickness, and foam strength. The tearing load and energy absorption decrease with the increase of the bending radius. It is found that these factors have a crucial influence on the trouser tearing fracture characteristics of the metal foam sandwich plate. The present theoretical model can effectively predict the trouser tearing fracture characteristics of the metal foam sandwich plate. Thu, 01 Jan 2026 00:00:00 GMT http://yetl.yabesh.ir/yetl1/handle/yetl/4316086 2026-01-01T00:00:00Z http://yetl.yabesh.ir/yetl1/handle/yetl/4316085 Area-Preserving Configuration of Holes in an Elastic Solid Under Plane Deformation: Implications for Mechanical Insensitivity of Liquid Inclusions Zhang, Yu-Hao; Miao, Kui; Dai, Ming Abstract. This article studies an inverse problem in plane elasticity concerning the preservation of the cross-sectional area of a hole under remote loading. The problem is motivated primarily by the need to stabilize internal fluid environments in flexible structures and microfluidic systems, for which deformation-induced area change may lead to an internal pressure increment and consequently alter the mechanical response of the surrounding structure. Restricting attention to plane deformation, we consider a cylindrical fluid inclusion of arbitrary shape and seek combinations of far-field loading and inclusion geometry such that the cross-sectional area of the inclusion remains unchanged. Under this condition, the pressure increment inside a compressible liquid inclusion vanishes, and the problem can be equivalently treated as that of an area-invariant, traction-free hole in an infinite elastic plane. By exploiting the complex variable method for plane elasticity, we derive for an arbitrary constant far-field loading the explicit condition imposed on the configuration of the hole for the corresponding area-invariance requirement. It is shown that in terms of combinations of symmetric hole shapes and pure shear loadings, the area invariance is achieved only when the symmetry axis of the hole is aligned with one of the principal directions of the shear loading, except for the cases of special symmetric hole shapes (e.g., circular, hypocycloidal, regularly polygonal) in which the area invariance can be always ensured for arbitrary orientations under pure shear loading. For biaxial tensile/compressive loadings, several representative numerical examples are presented to illustrate the evolution of the desired hole shapes relative to the ratio of the biaxial loading. Thu, 01 Jan 2026 00:00:00 GMT http://yetl.yabesh.ir/yetl1/handle/yetl/4316085 2026-01-01T00:00:00Z http://yetl.yabesh.ir/yetl1/handle/yetl/4316084 A Lattice-Based Theory for Kinematics and Constitutive Responses of Warp-Knitted Textiles Under Multiaxial Loading Xu, Junjun; Wang, Zelong; Chan, Ka Hung; Chen, Xian Abstract. Warp-knitted textiles often exhibit an effectively isotropic mechanical response under multiaxial loading despite their anisotropic knitting architectures, yet a quantitative theoretical explanation remains lacking. In this work, we proposed a lattice-based kinematics and constitutive theory that directly links warp-knitted architecture to macroscopic uniaxial and biaxial mechanical behavior. The fabric is modeled as a two-dimensional lattice of looped yarns, from which uniaxial and biaxial constitutive responses are derived based on yarn extension between neighboring looped braids. Systematic uniaxial and biaxial tensile experiments, combined with surface-resolved digital image correlation, verify the theoretical predictions and reveal an effectively isotropic biaxial response across loading orientations. Full-field strain measurements further confirm that deformation is governed by loop rotation and interlocked entanglement between neighboring wale braids. These results establish an architecture-driven framework for understanding the mechanics of warp-knitted textiles and provide a foundation for modeling multiaxial deformation in knitted fabrics. Thu, 01 Jan 2026 00:00:00 GMT http://yetl.yabesh.ir/yetl1/handle/yetl/4316084 2026-01-01T00:00:00Z http://yetl.yabesh.ir/yetl1/handle/yetl/4316083 Inverse Design of Metamaterials With Adaptable Force–Displacement Characteristics Güner, H. Gökçen; Dayal, Kaushik; Ion, Alexandra Abstract. Metamaterials with tailored force–displacement characteristics hold significant promise for applications ranging from soft robotics and energy dissipation to biomedical devices such as prosthetic sockets, where distinct regions of a structure must simultaneously satisfy fundamentally different mechanical requirements. Existing inverse design frameworks, however, are restricted to single-loading conditions and homogeneous desired behaviors, limiting their utility in real-world scenarios where complex, spatially varying mechanical demands must be met within a single continuous material. We present an inverse design method that closes this gap by combining finite element simulation, surrogate optimization, and machine learning within a unified framework. Starting from a fixed unit cell topology governed by 11 geometric shape parameters, we first construct a surrogate model that replaces each unit cell with a polynomial energy density, reducing the metamaterial-scale inverse problem to a tractable optimization over polynomial coefficients. A multi-output multilayer perceptron trained on finite element simulations then maps any required unit cell force–displacement response back to the corresponding shape parameters. We extend the formulation to multi-surface loading, enabling two qualitatively distinct force–displacement targets to be achieved simultaneously in different regions of the same structure. Fabricated prototypes tested under prescribed displacements confirm that the predicted responses, spanning superelastic, bistable, and constant-force behaviors, are reproduced with high fidelity. These results demonstrate a flexible and computationally efficient route to multifunctional metamaterial design under realistic, multi-condition loading environments. Thu, 01 Jan 2026 00:00:00 GMT http://yetl.yabesh.ir/yetl1/handle/yetl/4316083 2026-01-01T00:00:00Z