Condition assessment of mixed paved roads by GPR and CCR: Material properties

Abstract

Severe climatic conditions and poor methodology of maintenance and rehabilitation in Quebec make assessment survey of pavement a necessary however difficult task. In order to support prior results obtained with numerical modeling and to address optimal design of equipments, we determined physical properties of concrete, asphalt and foundation soil. These materials have been sampled from a street in the city of Montreal for which pavement had to undergo complete rehabilitation. The last complete rehabilitation of this street was done more than 30 years ago and material properties and composition were largely unknown. Before removal of pavement, we carried out a GPR survey with two distinct pairs of antennae (450MHz and 900MHz). Laboratory tests on concrete and asphalt were conducted on wet and dried samples, trying to reproduce the variability of physical properties due to changes in climatic conditions for a whole year. We measured complex dielectric constants in the range 50MHz-900MHz with a recently developed dielectric probe, and electrical resistivity using a simple laboratory system. Results show low variability of properties of asphalt depending of the saturation compared to larger variability in concrete. Finally all collected data are used as input to numerical modeling, and results compared with the survey data. © RILEM 2013.