IN SITU MEASUREMENTS OF STRAINS AND DEFLECTIONS IN A FULL-DEPTH ASPHALTIC CONCRETE PAVEMENT

In 1973, the Alberta Transportation Department constructed two full-depth asphalt pavement structures incorporating an extensive test facilitiy capable of recording stresses, strains and deflections under both static and moving traffic loadings. Data obtained from the facility have yielded specific information on the influence of axle loads, loading configurations, vehicle velocities and pavement temperatures on pavement-subgrade interfacial strains and surface deflections. This paper utilizes this information, together with pavement flexural fatigue and deflection criteria, and load equivalency concepts, to obtain quantitative assessments of relative destructive effects of various traffic loadings on pavement. Comprehensive traffic data for the two pavements has been collected, from which the accumulated equivalent single axle loading history has been developed and correlated with permanent deformation measurements. This in-service behavior is used to assess results obtained from recently developed procedures for prediciting pavement distress based on mechanistic parameters of stress, strain and deformation.