Implementation of AIMS in measuring aggregate resistance to polishing, abrasion, and breakage.

PDFTech ReportFHWA-ICT-14-014UILU-ENG-2014-2014R27-129Image analysisPolishing (Aggregates)AggregatesShapeTextureAngularityParticlesAbrasion resistanceProperties of materialsIllinoisIllinois Center for TransportationMahmoud, EnadOrtiz, EduardoUniversity of Illinois at Urbana-Champaign. Dept. of Civil and Environmental EngineeringUnited States. Federal Highway AdministrationIllinois. Dept. of Transportation. Bureau of Materials and Physical ResearchUS Transportation CollectionThe feasibility of using the Micro-Deval apparatus along with the second-generation Aggregate Imaging System(AIMS) to develop a procedure for measuring aggregate polishing resistance, and to measure aggregate shapeproperties was investigated. Eleven aggregate sources from the state of Illinois and neighboring states wereselected to develop an aggregate polishing experimental procedure using AIMS and Micro-Deval. AIMS wasused to measure aggregate shape properties with a special focus on aggregate angularity and surface texture,while Micro-Deval provided the needed polishing/degradation. Mathematical, statistical, and rate of texture lossanalysis indicated that all aggregate sources reached terminal texture at 210 minutes or less. Aggregateangularity followed the same trend, and terminal angularity was achieved at 210 minutes or less. As the polishingprocedure was finalized, aggregate shape properties were tested for 77 aggregate sources. Shape propertieswere measured before polishing and after polishing in Micro-Deval at 105 and 210 minutes, and a database wasdeveloped using Microsoft Excel. The research team also studied the number of aggregate particles that must bescanned in AIMS. Random sub-sampling and asymptotic analyses were conducted and it was concluded that120 particles were required. This finding was further evaluated by manual sampling of 120 aggregate particles.The manual sampling proved that 120 particles were enough for AIMS angularity and texture measurements