Evaluation of the Depth of Deteriorations in Concrete Bridge Decks with Asphalt Overlays Using Air-Coupled GPR: A Case Study from a Pilot Bridge on Korean Expressway

International Journal of Concrete Structures and Materials

Table 3 Summary of core survey.

ID	Core location		Pavement thickness (mm)		Waterproof layer		Rebar cover thickness (mm)		Rebar condition	Concrete deteriorated depth (mm)	Concrete condition
ID	X (m)	Y (m)	H _{asp, core}	H _{asp, GPR}	Bonding	Performance	H _{CC, core}	H _{CC, GPR}	Rebar condition	Concrete deteriorated depth (mm)	Concrete condition
C1	19	− 10.4	72	90	D	Loss				5	DC
C2	25	− 9.6	87	100	D	Loss	73	70	Clear	30	DC
C3	47.9	− 10.5	91	95	D	Loss				40	DC + DL
C4	52.7	− 10.4	94	95	D	Loss				55	DC + DL
C5	57.6	− 10.5	81	90	D	Loss				35	DC
C6	70	− 10.2	84	90	D	Loss				14	Other
C7	81	− 10.4	79	85	D	Poor				1	SC
C8	91	− 9.6	73	85	D	Loss				42	DC + DL
C9	94	− 9.8	82	85	D	Loss				35	DC
C10	103	− 9.3	80	90	D	Loss	72	80	Section loss	82	DC + DL
C11	110.1	− 9.8	82	90	D	Poor				3	SC
C12	119.6	− 9.5	79	85	D	Loss	70	60	Clear	30	DC
C13	133	− 10.2	75	80	D	Loss	53	80	Clear	6	SC

H_asp,core and H_asp,GPR are the thickness of asphalt overlay (pavement) measured from core samples and GPR survey, respectively.
H_cc,core and H_cc,GPR are the thicknesses of clear cover of top reinforcing bars measured from core samples and GPR survey, respectively.
D de-bonding, DC decomposition of concrete constituents, SC scaling, DL delamination.