| Title |
DETERIORATION OF COATINGS APPLIED TO REINFORCING BARS: LONG-TERM OUTDOOR EXPOSURE AND CORRELATION TO RAPID SCREENING TESTS
|
| Accession No |
00759705 |
| Authors |
Phelps, L L; McDonald, D B |
| Journal Title |
Journal of Protective Coatings & Linings
Vol. 15
No. 12 |
Corp. Authors
/ Publisher |
Technology Publishing Company ; Steel Structures Painting Council
|
| Publication Date |
19981200 |
| Description |
14 p.;
Photos(4); References(9); Tables(4) |
| Languages |
English
|
| Abstract |
In 1993, the Federal Highway Administration initiated studies to identify organic-coated; inorganic-, ceramic- and metallic-clad; and solid metallic reinforcing bars that might have a design life of 75-100 years in concrete. As part of the 5-year program, tests were conducted on the outdoor durability of organic-coated bars. This paper describes natural outdoor tests conducted on 10 different types of organic-coated reinforcing bars, along with five accelerated laboratory tests to simulate the out-of-doors environment. Exposure periods for organic-coated bars are significantly shorter than those typically expected for other protective coating systems applied to exterior structures. Thus, the natural outdoor testing was conducted for periods of only 6 months and one year. Five bendable epoxies and five nonbendable coatings--four epoxies and one vinyl--were evaluated. Weathering tests included outdoor weathering, cyclical salt fog exposure, cyclical salt fog/fluorescent ultraviolet (UV) cyclical weathering exposure (CSF/FUV), cyclical salt/fog carbon arc UV cyclical weathering exposure (CSF/CUV), conventional salt spray exposure, and conventional salt spray/carbon arc UV cyclical weathering exposure. None of the accelerated weathering tests precisely ranked the results of all exposed specimens with the results of specimens exposed to 12 months of natural outdoor exposure. Of the five accelerated weathering tests, rankings developed from results of CSF/CUV correlated most closely with those of 12 months of outdoor exposure; however, specimens exposed to CSF/CUV tended to display more corrosion. Specimens from other tests did not compare favorably, particularly those of CSF/FUV--the ASTM D 5894 test. Specimens exposed to CSF/FUV appeared much more weathered, corroded, and deteriorated than specimens of any of the other tests conducted. Results suggest that the standard ASTM D 5894 cyclic test may not consistently select the best coatings for exterior exposure. |
Supplemental
Information |
Page Range: pp 48-56, 58-62 |
| TRT Terms |
Accelerated tests ; Accelerated weathering ; Bending ; Corrosion ; Cyclic tests ; Deterioration ; Deterioration by environmental action ; Epoxy coatings ; Field tests ; Fluorescence ; Laboratory tests ; Organic coatings ; Protective coatings ; Reinforcing bars ; Salt fog tests ; Ultraviolet light ; Vinyl resins ; Weathering |
| Identifier Terms |
U.S. Federal Highway Administration |
| Subject Areas |
H34 GENERAL MATERIALS; I35 Miscellaneous Materials; I34 Steels and Metals |
| Availability |
University Microfilms International Find a library where document is available
|
| TRIS Files |
HRIS |
| Database |
TRIS Online |
TRT
