Evaluation of resilient modulus estimation methods for asphalt mixtures based on laboratory measurements

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2010
Demirci, Canser
Resilient modulus is a property for bound and unbound pavement materials characterizing the elastic behavior of materials under dynamic repeated loading. Resilient modulus is an important design parameter for pavement structures because it represents the structural strength of pavement layers through which the thickness design is based on. In Turkey, the layer thickness design is performed using resilient modulus determined empirically from various published sources. Determining a layer modulus using empirical methods causes inaccurate design solutions, which directly affects the structural performance and the overall cost of pavement construction. In this study, the resilient moduli of bituminous mixtures are measured in the laboratory by the indirect tensile test procedure for eight asphalt concrete samples according to NCHRP and ASTM procedures. The measured moduli of samples based on the two procedures are compared with the predicted values calculated from various empirical methods using aggregate and binder properties. An evaluation of each estimation method is presented on the basis of its accuracy level. The results show that the Witczak predictive equation produces the closest estimation to the modulus of samples for both laboratory measurement methods.

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Citation Formats
C. Demirci, “Evaluation of resilient modulus estimation methods for asphalt mixtures based on laboratory measurements,” M.S. - Master of Science, Middle East Technical University, 2010.