Passive Control in a Continuous Beam under a Traveling Heavy Mass: Dynamic Response and Experimental Verification

Area of Science:

• Structural Engineering
• Mechanical Engineering
• Vibration Analysis

Background:

• Heavy moving masses on bridges induce vibrations dependent on load magnitude, speed, and structural properties.
• Uncontrolled vibrations can lead to potential structural damage, necessitating mitigation strategies.

Purpose of the Study:

• To analyze the effectiveness of a tuned mass damper (TMD) in reducing bridge span vibrations.
• To investigate the energy transfer dynamics between a bridge and a TMD using analytical and experimental methods.

Main Methods:

• Derivation of governing equations of motion using a Lagrangian energy balance formulation.
• Analytical solution employing the Laplace transform to study vibratory energy transmission.
• Experimental validation using a simply supported steel bridge model and a heavy moving mass.

Main Results:

• The TMD demonstrated a significant reduction in vibratory energy transmitted to the bridge span.
• Time histories, Fourier spectra, and spectrograms confirmed the TMD's damping influence.
• Experimental results corroborated the analytical predictions and validated the passive scheme.

Conclusions:

• The passive tuned mass damper (TMD) is a viable and effective solution for mitigating bridge vibrations caused by moving loads.
• The study confirms the efficacy of TMDs in absorbing vibratory energy, thereby enhancing structural integrity.