Full-Scale Structural Testing of Permeable Interlocking Concrete Pavement to Develop Design Guidelines

This paper summarizes research conducted to revise existing pavement thickness design tables for permeable interlocking concrete pavement (PICP) published by the Interlocking Concrete Pavement Institute (ICPI) in 2011. The study included a literature review, field deflection testing of existing projects and test sections, estimation of the effective stiffness of each layer in PICP structures, mechanistic analysis and structural design of a test track incorporating three different subbase thicknesses (low, medium, and higher risk), tests on the track with a heavy vehicle simulator (HVS) to collect performance data to validate the design approach using accelerated loading, refinement and calibration of the design procedure using the test track data, development of a spreadsheet based design tool, and development of revised design tables using the design tool. Rut development rate as a function of the shear stress to shear strength ratios at the top of the subbase and the top of the subgrade was used as the basis for the design approach. The revised design tables are based on subgrade soil properties, subbase aggregate properties, the number of 80 kN standard axle loads, and the number of days with standing water in the subbase. The minimum design thicknesses required to prevent subgrade rutting in the revised tables do not differ significantly from those in the 2011 ICPI publication, and are mostly less conservative.