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The current edition of the European standard for specifying paving grade bitumens (EN 12591) is based on empirical test methods, such as penetration and softening point. Since the USA and Canada successfully adopted the rheology based performance specification system, Superpave, the discussion whether to introduce rheology tests and develop performance specification has moved to Europe. Recently, a Comité Européen de Normalisation (CEN) proposal to start collecting rheology data for bitumens has been drafted. For low temperature performance assessment, an approach nearly identical to Superpave was selected; low temperature testing in a Bending Beam Rheometer (BBR) performed on long term aged bitumen. For high temperature performance assessment Superpave equiviscous testing was not adopted. An isothermal dynamic shear rheometer tests at 15, 40 or 60 °C were selected to be performed on short term aged bitumen instead. This paper offers a comparison between empirical and rheology test methods. It highlights the advantages and disadvantages of each testing system. It explains the philosophy in Superpave specification and the process by which the rheology test results are related to bitumen performance in asphalt. Current CEN proposal for rheology data collection is reviewed and suggestions to development of a performance based specification system are provided.

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