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Checking and Cracking — Failure Before Service a common issue: Plasticizers had evacuated from the lining film to a greater degree in these areas than in the areas that did not exhibit cracking and checking. It was reasonable to presume that the elevated temperature and dry conditions during prolonged exposure of the pipeline right-of-way was a contributing factor. Pipe sections with linings that were installed at the same relative time but stored in a more sheltered environment and not exposed to the extreme temperatures did not exhibit checking and cracking of the lining film. It's also reasonable to presume that, in this situation, with continued exposure to elevated temperatures, the observed checking was a precursor to eventual cracking of the lining film. environment and the material that would flow in the pipeline. In other words, the coatings were chosen based on the requirements of the pipes once they were installed underground. The selection did not anticipate or allow for the environment that the lining would be exposed to during the pipeline construction. An assumption was made that the pipe sections would be lined and joined within a shorter and more typical period of time, and VISIT ICRI AT WORLD OF CONCRETE BOOTH #S10539! The leading resource for education and information to improve the quality of repair, restoration, and protection of concrete. Evaluating the Environment RECENTLY UPDATED! On a typical pipeline construction job, coated and lined pipe sections are not usually sitting on the right-ofway for extended periods of time. It appears that the time that the lined pipe remained on the right-of-way prior to installation had a substantial effect on the installed lining system. Within the limited initial test set, several trends emerged: ICRI TECHNICAL GUIDELINE NO. 310.2R-2013 "SELECTING AND SPECIFYING CONCRETE SURFACE PREPARATION FOR SEALERS, COATINGS, POLYMER OVERLAYS, AND CONCRETE REPAIR" This guideline summarizes the capabilities, requirements, and limitations of the various methods used to prepare concrete surfaces for the application of protective sealers, coatings, polymer overlays, and concrete repair. Benchmark profles are included that provide visual standards for the purpose of specifcation, application, and verifcation. • Linings installed in pipe that did not sit on the right-of-way for extended periods and were buried quickly did not exhibit checking and cracking of the lining system. • Linings installed in pipe that remained on the right-of-way and were exposed to surface environmental conditions for extended periods of time exhibited checking and cracking failure proportionate to the exposure duration. UPDATES INCLUDE: • Surface retarders and handheld breakers added to surface preparation methods; • New appendix for selecting surface preparation methods; • Description of various test methods used to evaluate a prepared surface; and • CSP 10 added to show a more aggressive profle for concrete repair. CSP Chips and Guideline Guideline only New Set of 10 Chips only New 10th Chip only $111 Member / $173 Nonmember $35 Member / $57 Nonmember $90 Member / $129 Nonmember $5 Member / $7 Nonmember So how could this have happened? Expected Versus Actual When the coating product for lining the pipeline was selected, the specifications focused on the service ORDER NOW! Phone: (248) 848-3809 WWW.ICRI.ORG E-mail: info@icri.org Write in Reader Inquiry #279 COATINGSPRO JANUARY 2014 95