Applications of intermittent cathodic protection for control of rebar corrosion

Conference · Mon Dec 31 23:00:00 EST 2001

OSTI ID:898068

Ziomek-Moroz, Margaret; Cramer, Stephen D; Covino, Jr, Bernard S; Bullard, Sophie J; Russell, James H; Holcomb, Gordon R; Windisch, Jr, C F ^[1]; Soltesz, S M ^[2]

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1. PNNL
2. Oregon Dept. of Transportation

Rebar in concrete structures is susceptible to chloride-induced corrosion. Impressed current cathodic protection (ICCP) is frequently used to protect rebar against corrosion,. To take advantage of rebar passivity in concrete after ICCP is turned off, the Albany Research Center, in collaboration with the Oregon Department of Transportation and Pacific Northwest National Laboratory, is investigating applications of intermittent cathodic protection corrosion as a means for advancing corrosion control of reinforced concrete structures while extending the service life of thermal-sprayed zinc anodes. Corrosion rates of rebar in deaerated and oxygenated simulated pore water and quartz sand saturated with simulated pore water at pH 7 and 13 were determined using electrochemical and mass loss techniques. The rebar was passive at pH 13, but measurable corrosion occurred at pH 7. The use of sand prevented convective transport of reactants to and from the rebar, thereby substantially reducing the corrosion rate. In-situ Surface Enhanced Raman Spectroscopy (SERS) results indicated the presence of Fe304 and Fe (OH)2 on the rebar surface depending upon the polarization conditions. The amount of Fe304 decreased while Fe (OH)2 increased as the time of cathodic polarization increased.

• Research Organization: Albany Research Center (ARC), Albany, OR
• Sponsoring Organization: USDOE
• OSTI ID: 898068
• Report Number(s): DOE/ARC-2002-013
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANODES
CATHODIC PROTECTION
CONCRETES
CORROSION
PASSIVITY
POLARIZATION
QUARTZ
RAMAN SPECTROSCOPY
REINFORCED CONCRETE
Raman spectroscopy
SAND
SERVICE LIFE
TRANSPORT
US DOT
WATER
ZINC
impressed current cathodic protection
intermittent cathodic protection
linear polarization
passivity
pore water solution
rebar
reinforced concrete bridges