An optimization strategy utilizing the Honey Badger Algorithm (HBA) is formulated in this article for the optimal design of truss structures with discrete variables under multi-load scenarios. HBA is implemented to optimize fundamental design criteria that involve the cross-sectional areas of the truss members. Structural evaluations are conducted by analyzing different cross-sectional configurations, with the primary objective of minimizing the total mass of the structure while satisfying stress and displacement constraints. The HBA is used as a metaheuristic optimizer to explore the design domain and converge towards optimal or near-optimal configurations. This approach is applied to several benchmark examples, including planar and spatial trusses, and the results are compared with existing studies to assess the algorithm's performance. The optimization outcomes confirm the effectiveness and robustness of HBA in solving constrained structural optimization problems, as well as its ability to achieve rapid convergence toward high-quality solutions.
In this study, the data from a sensor for generating and measuring a plate's surface deflection was compared against the data from simulations with the finite element method. The sensor deformed the plate by using a vacuum pressure. The deflection was measured by utilizing photometric stereo techniques with data from an RGB-camera. A finite element model consisting of the relevant parts of the sensor and a volume element model of the plate under a load equivalent to the vacuum pressure of the sensor was used. The material constants of the real plate were approximated by using digital image correlation and applied to the finite element model. The measured deflections and their numerical partial derivatives were compared to their simulated counterparts. The sensitivity of the sensor between multiple images was studied against small changes in simulated deflections when the material constants were varied.
This paper examines the torsion of beams with undeformable cross-sections. A novel approach is proposed, in which an interpolated warping function is defined as a continuously differentiable function across the entire cross-sectional area. This formulation enables methods that require the warping value to be accessible as a continuous function at any point within the section. The approach facilitates deformation analysis within the framework of three-dimensional elasticity, employing continuum-based beam elements governed by general continuum mechanics material laws. The primary objective of this study is to establish a general method for determining warping functions for complex cross-sections, intended for future applications in the absolute nodal coordinate formulation. The approach does not replace earlier methods, which have proven highly efficient and even suitable for hand calculations. Instead, it provides a general-purpose framework that can yield improved accuracy in certain cases. Whereas traditional treatments distinguished primarily between open and closed profiles, the present formulation emphasizes the importance of recognizing the nature of each profile and selecting interpolation methods accordingly.
Additive manufacturing is typically used for rapid prototyping and the production of small to medium quantities of complex parts. The quality of 3D-printed metallic parts depends on the printing process parameters and material behaviour. In order to characterize the mechanical properties of materials, the nearly non-destructive micro-indentation hardness testing of additively manufactured steel and aluminium alloy using Laser Powder Bed Fusion technology was investigated in this study. The micro-hardness and modulus of elasticity of hot work tool steel AISI H13 (1.2344) were evaluated to study the influence of printing parameters, such as laser power and laser scanning speed. While no pile-up or sink-in effects were detected in the steel samples, the pile-up effect was observed during the hardness measurement of the aluminum alloy AlMg1Si AA-6061. Since the pile-up effect leads to an overestimation of the measured hardness, a correction factor was applied to account for this deviation, resulting in an adjusted value approximately 7% lower than the initially measured hardness for the aluminum alloy. In addition, the statistical reliability of the measured hardness properties of the 3D-printed metals was evaluated using the Weibull distribution. It was demonstrated that the indentation test is highly suitable for analyzing small additively manufactured samples with relatively little effort while delivering high statistical reliability and providing meaningful insights into the mechanical properties of the materials, such as micro-hardness and indentation modulus.
We present a coupled chemo-mechanical and fracture mechanics-based model capable of predicting the onset of hydrogen-induced macroscopic crack growth as a function of material, loading and environmental variables. The model is implemented using the commercial multi-physics simulation package COMSOL and solved as a coupled deformation–diffusion problem to define a fracture criterion as a function of residual and externally applied loads and hydrogen concentration. The local hydrogen-induced material damage is approximated by a parametric dependency of local fracture resistance on hydrogen concentration. As an example, we demonstrate the ductile-brittle transition of the failure pattern of a double-notch specimen under tension w/o and w/ hydrogen loading.
