ABSTRACT
Performance related testing of bituminous materials in now familiar in the United Kingdom and has been incorporated into some specifications for design and evaluation, such as those in the Manuals of Contract Documents for Highway Works and the British Board of Agrément Highway Authorities Products Approval Schemes. At the same time, development of standard Test Methods for performance related testing is still ongoing (for example, for stiffness, fatigue and deformation resistance testing).
Particular attention is drawn to the laboratory determination of stiffness of bituminous materials in this paper. Stiffness testing is probably the most frequently used performance related test. However, different types of testing equipment are available in the UK market. The variability associated with these various pieces of equipment, and the practical implications of this variability on the test result, is addressed in this paper in a simplified fashion. Finally, practical guidelines for assessing stiffness test results are introduced, aiming to help technicians and engineers to assess the data, if necessary to correct them, when the required test parameters (if any) cannot be achieved due to limitations of the testing equipment.
