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45 CHAPTER SEVEN CONCLUSIONS AND FUTURE RESEARCH NEEDS CONCLUSIONS states and provinces where cathodic protection would be an appropriate technology to implement, deicing salt Based on the results of the survey and the discussions usage is sufficiently high, more than 5 tons per lane- presented in this report the following conclusions can be mile per year. For coastal states and provinces, marine drawn: exposure is also a significant cause of corrosion on rein- forced concrete structures. 1. Agencies that have successfully implemented cathodic 8. A majority of agencies have standard procedures, pro- protection technology have experienced a reduction in tocols, or methodologies for conducting corrosion the frequency and cost of bridge maintenance and an condition evaluations, analyzing the data, and selecting increase in the service life of their bridge structures. To alternatives. The test methods used by the agencies in accomplish this they had to acquire a good understand- corrosion condition evaluations appear to be adequate; ing of the technology and expertise in the technology. however, no information on the quality of these evalu- 2. Cathodic protection is accepted as a viable corrosion ations is available. control technology by some agencies. However, the use of this technology is limited. 3. The use of cathodic protection technology has been REQUIREMENTS FOR IMPLEMENTATION declining. From 1970 to 1989 approximately 275 OF CATHODIC PROTECTION TECHNOLOGY bridges were outfitted with cathodic protection sys- tems; in the next 20 years, almost 240 bridges had been Based on the results of the survey and the literature review, added to the inventory of 21 agencies. However, there the following would improve the quality of the implementa- is some promise of growth during the next 5 years. The tion and increase the confidence in the technology, thereby technology is actively used only by the states of Florida, resulting in an increase in its use. Missouri, and Oregon and the provinces of Alberta, New Brunswick, and Ontario. 1. Dissemination of information on the cost benefits of 4. The primary disadvantages to the use of cathodic using cathodic protection systems and success stories protection technology are the initial cost and the bur- from user agencies by either the National Association den of monitoring and maintaining the systems. of Corrosion Engineers (NACE) or FHWA, or both. Past disappointing experience has also slowed the 2. It would be useful if training in the technology were implementation of this technology. Many of the dis- offered by a national program such as NACE or the appointing experiences resulted from the use of the National Highway Institute. previous generation of materials and inappropriate 3. Development of standards and specifications for selec- implementation of the technology. In addition, most tion, design, installation, and monitoring and mainte- agencies do not have the resources to implement the nance of the systems. It is important that user agencies cathodic protection technology and have chosen adopt a standardized protocol for corrosion condition not to make a commitment toward developing such evaluation, analysis of data, selection of alternatives, resources. design of the system, specifications for installation, and 5. Galvanic cathodic protection is becoming more attrac- protocols for monitoring and maintenance. tive than impressed current owing to lower monitoring 4. Departments of transportation might acquire at least and maintenance requirements. Future research and one individual, if not more, with expertise in cathodic development might be focused in this direction. protection technology. Although the individual may 6. Competition and innovation are required in the indus- not be able to perform all of the necessary tasks, he or try to improve the quality of products and services. she would be knowledgeable enough to supervise 7. Corrosion is, at a minimum, a moderate problem for the others or manage consultants. It would be desirable for majority of the departments of transportation in North the individual to possess the NACE Cathodic Protection America, although for some it is a severe problem. Sev- Specialist Certification. eral agencies that are expected to experience severe cor- 5. It is best to use anode materials and configurations rosion problems did not respond to the survey. In many that are prequalified, meet a certain performance and