Transition to Superpave Performance Grades in Western Canada

摘要

While most of North America has adopted Superpave? Performance Grading (PG) for paving asphalts,penetration-based specifications are still used in Western Canada. Heavy asphaltic crude oils available inWestern Canada have historically produced an excellent quality paving asphalt. Therefore, there was littleneed for specification changes. However, increasing use of polymer modified asphalts and/or PG by somejurisdictions in Western Canada, cross-border technical specifications harmonization, and an ongoing needto certify paving grades in both specifications has initiated a move towards the Superpave PGspecification. In recent years, some Western Canadian provinces have adopted the Superpave specificationfor paving grades. The adoption was relatively fast, building on the experience of the rest of the continentand Eastern Canada, specifically.The objective of this study is to compare asphalt qualities of a relatively large set of asphalts distilled frompredominantly Western Canadian crude oils in both penetration-based and Superpave specifications. Theability of both specifications to predict fundamental rheological behaviour is analyzed. Moreover, theadditional low temperature restrictions added to standard Superpave specification by some jurisdictionsare analyzed and their relevance is discussed.