Mechanics of Materials and Structures

Mechanics of Materials and Structures

Experimental-numerical analysis of thin-walled box structures with integral corrugated stiffeners, subjected to torsion

The study presents the results of model experimental investigations and nonlinear numerical analyses of thin-walled, two-segment box structures with various configurations of integral corrugated stiffeners. The models for experimental testing were fabricated using additive manufacturing techniques. Five variants of the structure were examined, including a reference configuration without reinforcement. The experimental investigation was carried out using a dedicated test rig. Numerical representations of the investigated models were developed and subjected to nonlinear analyses using finite element method-based software. The adequacy of the numerical results was assessed through comparison with experimental data. The objective of the study was to determine the effect of different forms of the proposed structural solution on the magnitude of the critical load and the nature of post-buckling deformation.

ON THE INSTABILITY OF 0RTHOTROPIC CYLINDERS

Mechanics of Materials and Structures

Research on Asymmetric Gear Stiffness

To meet the need for optimizing the dynamic performance of asymmetric gear transmissions operating under high-speed and heavy-load conditions, this study presents a refined stiffness modeling approach. A tooth-surface contact stiffness model is formulated based on Hertzian contact theory. By integrating the energy method, a coupled stiffness model is established that incorporates bending, shear, axial compression, and foundation stiffness components. Stable curves depicting the variation of mesh stiffness with the path of contact are subsequently derived by leveraging the principle of stiffness superposition. The findings demonstrate that the proposed mathematical model accurately represents the stiffness behavior of asymmetric gears as governed by the changing contact length, thereby providing a theoretical foundation for enhancing gear dynamics and extending the service life of transmission systems.

A noble analytical solution for the size of rectangular footing subjected to axial, bending, and surcharge load

This paper introduces a comprehensive mathematical framework for the design of rectangular reinforced concrete footings under axial load, surcharge, and biaxial moments, accounting for both fully and partially supported contact conditions. The proposed method presents a set of closed-form equations obtained via integration, which incorporate changes in soil pressure distribution resulting from eccentric loading. As the noble contribution, a key parameter named compression fraction λ, is added to differentiate between complete and partial soil-footing interaction. The model incorporates surcharge—a component overlooked in previous formulations—and generalizes the concept of equal width typically employed in footing design. Parametric analyses reveal the model’s responsiveness to fluctuations in vertical load, moments, soil bearing capacity, and aspect ratio. Results indicate consistent and rational tendencies, with the footing area expanding under elevated loads or diminished bearing capacity, and contracting with increased soil strength. A comparison with Landeros’s model demonstrates that the proposed method produces more economical designs, with footing area reductions of up to 49.91%. The incorporation of surcharge and the capacity to manage partial compression render the presented equations a reliable and effective resource for structural engineers pursuing precise and material-efficient footing designs under complex loading scenarios.