Influence of Excitation on Dynamic System Identification for a Multi-Span Reinforced Concrete Bridge

Table 5

Natural frequencies generated using random forced excitation.

Mode	Natural frequencies (Hz)
	Eigenvalue analysis	Random-Forced vibration phase			Random-free vibration phase
		Avg.	𝜎	Error (%)	Avg.	𝜎	Error (%)
1	2.480	2.477	0.047	0.12	2.479	1.542E-07	0.04
2	4.024	4.050	0.072	−0.65	4.019	1.488E-06	0.12
3	5.695	5.600	0.117	1.67	5.680	1.696E-06	0.26