Finite element analysis of transverse vibrations of beams subjected to axial compressive loads

• Main Author: Hoe, Yee Siang
• Other Authors: Sellakkutti Rajendran
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2023
• Subjects: Engineering::Mechanical engineering::Mechanics and dynamics
• Online Access: https://hdl.handle.net/10356/166907
• Institution: Nanyang Technological University

Beams are commonly used in many real-world engineering applications such as bridges, buildings and aircraft structures. They are often subjected to many kinds of loads such as bending moments, shear forces and axial loads. It is also understood that axial loads can significantly affect the natural frequencies and the vibration characteristics of beams. In this final year project (FYP), the effects of axial compressive load on the vibration characteristics of beams with different cross-sections are studied using the finite element method. The type of beams that are analysed includes a 2D rectangular cross-section beam and a 3D T-shape cross-section beam. ANSYS Mechanical APDL is used to model the beams and to carry out the vibration analysis. The scope of analysis covers the free, forced and transient vibration responses for both beams subjected to increasing compressive load. The vibration characteristics are obtained for both beams and the results are analysed. It is discovered that, under free vibration analysis, the natural frequencies for both beams decrease with increasing compressive load, whereas, under forced vibration, the peak amplitudes of vibration increase with increasing compressive load. As the compressive loads tend to reduce the natural frequencies, the corresponding resonant (peak) amplitudes occur earlier than the case without compressive load. As for transient vibration, the peak amplitudes and the period of oscillations increases with increasing compressive load.