Record Details
Development of a test method for assessing water repellency and derived physical stability of preservative systems for railroad ties
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Development of a test method for assessing water repellency and derived physical stability of preservative systems for railroad ties |
| Names |
Beck, H. Greeley
(creator) Morrell, Jeffrey J. (advisor) |
| Date Issued | 2014-09-22 (iso8601) |
| Note | Graduation date: 2015 |
| Abstract | Resistance to moisture uptake is an important attribute of some wood preservatives and can help reduce moisture cycling that leads to the development of deep checks. While the potential for preservative treatments to help improve wood/moisture interactions is acknowledged, there are no tests that specifically evaluate this performance parameter. Checking is a particularly important issue for railroad ties and often causes tie failures. A number of new wood preservatives have recently become available on the tie market and it would be useful to have a standardized test method that compares water repellency and derived physical stability of these preservatives. The objective of this study was to develop one such test method. The role of water repellency on dimensional stability was examined using non-treated and creosote-treated red oak, white oak and black gum samples exposed to 3-4 wet/dry cycles. Dimensional stability was assessed by measuring two checking variables - counting the number of checks on the outer most tangential surface and measuring the area of the largest check on the same surface. Check frequency tended to increase with moisture cycling, while largest check area provided a less consistent measure of dimensional change. Creosote treatment did not significantly enhance dimensional stability compared to non-treated samples as measured by check frequency. Water repellency of non-treated, creosote-treated and copper naphthenate-treated samples was assessed by water droplet contact angle. Creosote treatment significantly improved water repellency, but copper naphthenate-treated samples did not differ significantly from non-treated controls. Although creosote treatment did not substantially affect check development, increased water repellency provided by the preservative would likely reduce check development for railroad ties in service by preventing them from reaching the elevated moisture levels necessary for checking to occur. |
| Genre | Thesis/Dissertation |
| Access Condition | http://creativecommons.org/licenses/by/3.0/us/ |
| Topic | Water Repellency |
| Identifier | http://hdl.handle.net/1957/53328 |
