Decision Matrix Analysis of Impact Sounding Test Method to Determine Interlayer Condition of Concrete Bridge Deck

Table 4

Summarized description of the proposed zonal condition level of bridge deck pavement.

Zone	Condition	Description
		Frequency spectra	Visual inspection
a	Severe	Peak frequency less than 600 Hz	Deterioration depth is greater than 25 mm; Asphalt concrete is heaved; Traces of moisture are remarkable
b	Debonded	Peak frequency of 1,000 to 1,300 Hz, peak amplitude higher than 50 Pa^2/Hz	Asphalt concrete is completely detached from the concrete deck
c	Fair	Peak frequency of 1,000 to 1,300 Hz, peak amplitude lower than 50 Pa^2/Hz	Surface of concrete deck shows minor scaling
d	Good	Peak frequency higher than 1,500 Hz	Good condition, no inspected damage on the surface of concrete deck