| dc.description.abstract | Five structural steel coating systems (Wasser, Carboline, Valspar, Watson and Superior) were selected for evaluation and sent to Corrosion Control Consultants & Labs, Incorporated (CCCL) to be tested. In addition to the laboratory tests, three of the coating systems were applied to structural steel in the field. A visual inspection of the coating system was made and the results were recorded . After reviewing and analyzing the results of the CCCL tests and the visual inspection, a cost analysis was performed as well as a survey of the tests and criteria that other transportation agencies use to certify and accept coating systems. The analysis revealed that four of the seven evaluation procedures, Salt Fog, Envirotest, Taber Abrasion and Fluorescent UV, yielded useful and informative results . By eliminating three of the tests used for evaluation, Relative Humidity, Prohesion testing and visual inspection, and reducing the time that each test was performed from five thousand hours to two thousand hours, the cost o f evaluating each coating system was also reduced. Laboratory testing was recommended to create a performance-based specification for accepting coating systems for use on bridge structural steel. In order to obtain an equitable and balanced evaluation of how each coating system performs, it was recommended that the results of each test be evaluated using a weighted rating system . A weighted rating system using the four tests selected gave the best results that can be obtained in the least amount of time and at the lowest cost. The tests used will be assigned weights as follows : Salt Fog (20%), Envirotest (30%), Taber Abrasion (25%) and Fluorescent UV (25%). Coating systems that receive a total rating of at least 85% will be considered acceptable . In this evaluation, the Carbo line and Valspar systems passed these criteria with a rating greater than 85%. | |
