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出版United States. Office of Fossil Energy., 2004
URLhttp://books.google.com.hk/books?id=IfwCkAEACAAJ&hl=&source=gbs_api
註釋The Oregon Department of Transportation (Oregon DOT) maintains more than 120 coastal bridges; many are reinforced concrete structures over 15 m (50 ft) in length. Twelve of these bridges are historic structures. Oregon DOT is concerned about the ongoing deterioration of these bridges, rising maintenance and repair costs, and the need to protect Oregon's large investment in coastal bridges. Over 80,000 m2 (850,000 ft2) of coastal bridge surface have been repaired and protected from further chloride-induced corrosion damage by using conductive coating anodes. Most of the anode area is thermal-sprayed (TS) Zn. Other anode materials include TS Ti, Zn-hydrogel, and conductive carbon paint. TS Zn anodes are estimated to have a service life exceeding 25 years but exhibit increasing anode polarization with age. Catalyzed TS Ti anodes develop no significant anode polarization and have exhibited stable long-term performance over 8 years of service. Galvanic Zn-hydrogel anodes produce a stable protection current with no evidence of aging effects over 6 years of service. The conductive carbon paint anode operates at a low anode current density and consumption rate with a low rate of acidification at the anode-concrete interface, which has contributed to a stable protection current over 17 years of service.