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| Report No. | IP21(jot this number down to order) |
| Title | Cold Climate Condition Survey of Asphalt-Rubber Membranes |
| Author(s) | Schnormeier, Russell H., P.E. |
| Publisher | ARPG |
| Pub. Date | 1991 |
| Pages | 16 pages |
| Keywords | |
| Description | An evaluation of the application of Asphalt-Rubber in cold climates was undertaken to dispel the misconception that Asphalt-Rubber only works in hot, dry climates. This survey was conducted on Stress Absorbent Membranes (SAMs) and Stress Absorbent Membrane Interlayers (SAMIs). Climatic regions included in this study are dry cold, wet cold and frequent freeze thaw. All Asphalt-Rubber projects were placed before 1983, the majority are more than 10 years old. Freeze index for these projects range from 500 to 4,500 degree days, with annual rainfall from 15 to 60 inches per-year. The survey revealed early problems with the loss of cover aggregate, which improved as bar distribution, application rates and type of aggregates used, were modified. In spite of aggregate loss, Asphalt-Rubber sealed and stopped crack reflection of alligator or block type cracks. Without crack preparation with Asphalt-Rubber or other methods, Asphalt-Rubber as a membrane alone in SAMs and SAMIs have not been effective in stopping transverse cracking in cold climates. However, neither have other materials or methods. This study has revealed that large cracks must be pre-prepared. Projects where transverse cracks were pre-prepared, did not reflect through the surface. Secondary cracking and spalling have been reduced even in the membranes. Asphalt-Rubber in cold climates has the same improved properties in durability, flexibility and temperature susceptibility as it does in warm climates compared to standard asphalt under the same conditions. The survey indicates Asphalt-Rubber does last at least twice as long as standard asphalt, and in many cases, three and four times as long. The mix and application procedures for Asphalt-Rubber in the late 1970s are not the same today. Many problems are attributable to the learning process in the development of Asphalt-Rubber. There is also a tendency to forget the original pavement condition and make a critical evaluation of Asphalt-Rubber applications by the condition of the pavement today. |
| Postage | $ 2.00 : U.S. $ 2.20 : Canada/Mexico $ 2.40 : Rest of the World |