Assessment of Modern Roadways Using Non-destructive Geophysical Surveying Techniques

Abstract

The main purpose of modern roadways is to provide roadway users with both a comfortable and safe ride to their destinations. As such, they need pavements in good physical conditions to ensure safe and uninterrupted transportation of the public. During the previous decades, roadway engineers’ interests have shifted towards maintenance and rehabilitation of existing pavement structures, rather than the construction of new structures. Nevertheless, pavement condition assessment (PCA) remains imperative both during construction for quality assurance purposes and during roadways’ service life for efficient maintenance planning. Research and current practices have shifted towards a broadened utilization of advanced non-destructive testing systems that enable non-invasive PCA. The current investigation aims to provide a comprehensive overview of the geophysical methods available for modern roadways’ assessment. Geophysical surveying techniques including ground penetrating radar (GPR) and those based on stress waves theory can substantially improve PCA. They cover roadway applications including layer thicknesses determination, stiffness estimation of asphalt and concrete pavements, as well as the determination of physical properties, subsurface defects detection and most recently density monitoring. In particular, it is demonstrated that GPR can assist pavement engineers at all stages of PCA from the construction process through density control and compaction monitoring. Furthermore, throughout a roadway’s service life, GPR can be effectively incorporated as a supplementary tool for monitoring and evaluation within a pavement management system, contributing to optimizing roadways design and maintenance, preserving durable and sustainable structures, ensuring cost savings for road authorities and highway operators through enhanced decision-making processes.