Delamination Detection of Reinforced Concrete Decks Using Modal Identification

Table 7

The damping ratios identified by using SSI method from experimental specimens.

—		Undamaged	22.2% delaminated	51.9% delaminated	74.1% delaminated
From random; responses	Frequency (Hz)	31.61	26.83	27.56	24.31
	𝜉 (%)	1.05	1.34	1.68	1.71
From impact; responses	Frequency (Hz)	31.62	26.87	27.44	9.15
	𝜉 (%)	1.25	1.46	1.32	1.43