AGGREGATE TOUGHNESS / ABRASION RESISTANCE AND DURABILITY TESTS RELATED TO ASPHALT CONCRETE PERFORMANCE IN PAVEMENTS By
i DISCLAIMER The contents of this report reflect the views of the authors who are solely responsible for the facts and the accuracy of the data presented herein. The contents do not necessarily reflect the official views and policies of the National Center for Asphalt Technology of Auburn University. This report does not constitute a standard, specification, or regulation. ii ABSTRACT Numerous tests have been developed to empirically characterize aggregate without, necessarily, a strong relationship with the performance of the final products incorporating these aggregates. This seems to be particularly true for aggregate " toughness and abrasion resistance " and " durability and soundness. " The purpose of this research was to identify and evaluate toughness/abrasion resistance and durability/soundness tests for characterizing aggregate used in asphalt concrete and to determine those test methods that best correlate with field performance. Based on a review of literature and specifications, laboratory tests for characterizing aggregate toughness/abrasion resistance and durability/soundness were selected. Sixteen aggregate sources with poor to good performance histories were identified for evaluation with the selected suite of tests. Performance histories of pavements containing these aggregates in asphalt concrete layers were established through personal contacts with state transportation agencies and performance evaluation questionnaires. Aggregate properties from laboratory tests were correlated with field performance. The Micro-Deval and magnesium sulfate soundness tests provide the best correlations with field performance of asphalt concrete, and are recommended for characterizing aggregate toughness/abrasion resistance and durability/soundness.
INVESTIGATION INTO THE SOURCE AND PROGRESSION OF RAILWAY TRACK BALLAST LAYER FOULING MATERIAL FOR THE CN JOLIETTE, QC SUBDIVISION
Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2011-09-27 10:01:46.141
MEASUREMENT OF ROAD SURFACE SHAPE USING A LASER SENSOR
A contactless laser sensor has been developed that is capable of measuring vertical height from the road surface up to 3300 times per second. It has a resolution of 0.282 mm over its working range of 72 mm, which is centred at a distance of 270 mm from the sensor. The sensor has been employed in the development of computer controlled systems for measuring, at traffic speed, the longitudinal profile, the macrotexture and the wheel-track rutting of a road surface. The operation of the sensor and its applications to the measurement of surface shape are described. (Author/TRRL)