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Design Solutions for Slender Bars with Variable Cross-Sections to Increase the Critical Buckling Force.
Marius Florin Botis1, Camelia Cerbu2
1Department of Civil Engineering, Faculty of Civil Engineering, Transilvania University of Brasov, B-dul Eroilor, No. 29, 500036 Brasov, Romania.
Materials (Basel, Switzerland)
|September 9, 2022
Summary
This study introduces a finite element model to enhance the critical buckling force in civil engineering structures. Trapezoidal variations in cross-section significantly increase stability, outperforming constant sections.
Area of Science:
- Structural Engineering
- Mechanical Engineering
- Computational Mechanics
Background:
- Slender bars in large metal civil constructions are susceptible to stability loss under compression.
- Existing literature lacks comprehensive design solutions for increasing the critical buckling force of bars with variable cross-sections.
Purpose of the Study:
- To develop and present a numerical finite element model for analyzing stability loss in bars.
- To comparatively analyze methods for increasing the critical buckling force of bars with stepwise and continuous cross-section variations.
Main Methods:
- An analytical model was developed to compute critical buckling force for stepwise variable cross-sections.
- A finite element model was created and validated using MATLAB for slender bars.
- The numerical model was adapted for bars with continuous variation in the moment of inertia.
Main Results:
- A trapezoidal variation in the second moment of inertia increased the critical buckling force by 3.556 times compared to a constant section bar.
- A specific stepwise variation in cross-section yielded a critical buckling force increase of 3.427 times, comparable to sinusoidal variation.
Conclusions:
- Variable cross-section designs, particularly trapezoidal and specific stepwise variations, offer significant improvements in critical buckling force for civil engineering applications.
- The proposed finite element model provides a validated tool for analyzing and optimizing the stability of structural elements with varying cross-sections.
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