Development of a Frequency-Adjustable Tuned Mass Damper (FATMD) for Structural Vibration Control

Table 5

Dynamic responses in the midspan of the bridge with and without the FATMD.

Earthquake	Imperial Valley	Kobe	Borrego
Peak displacement (mm)
Uncontrolled	1.29	1.65	1.80
With FATMD	0.69	0.85	0.98
Vibration reduction ratio (%)	46.51	48.48	45.56
Peak acceleration (m/s^2)
Uncontrolled	2.34	3.21	2.74
With FATMD	1.62	1.55	1.59
Vibration reduction ratio (%)	30.77	51.71	41.97