Airport Pavement & Aggregate Crushing Presented by Kristen Blake, Shelby Brevogel, Lauren Hillis, Nate Rahaim, and Andrew Short

Under the micromechanics of crushing by considering individual particle crushing strengths and triaxial shear tests on laboratory scale samples Model the densification of the soil layers under airport pavements using the gyratory compactor and compare results to field compaction Objectives

Leonards, 1995

Large Scale Versus Small Scale Super Gyratory Compactor Field Trafficking versus

Past Work Data acquisition from FAA testing facility Effort to replicate data within the laboratory Computations to create a comprehensible relationship

Current Work Concentration on P-154 Energy Relation Determination Density and Energy Calculations

Energy based approach Reason being crushing in sub layers

Background -When particles break, it will break into similar shapes as the original particle -Higher coordination # will result in large particles breaking -When particles break, it will break into similar shapes as the original particle -Higher coordination # will result in large particles breaking McDowell (1996) - Particles eventually reach a stable gradation, once the crushing of particles result in decreased volume Coop (2004)

Equipment Skyscan 1072 micro-CT Triaxial Compression Test

Particle Crushing Concrete Sand in crushingCalcareous Sand in Crushing

Triaxial Compression Tests

Soil Properties

Soil Failures

Goals Publish energy relation findings Determine inherent soil properties and crushing characteristics for Calcareous Sands from Triaxial tests Create Discrete Element Models of sand samples

Questions?