Pavement Integrity Scanner to Characterize Modulus Contrast between Near-Surface and Deeper Material in Concrete Pavements

Abstract

A major distress problem in rigid concrete pavements is early deterioration of near-surface layers. The quality of near-surface material governs the long-term performance of concrete pavement. If the near-surface material of the concrete layer is cured sufficiently well at an appropriate moisture and temperature, the concrete pavement system can be expected to endure fatigue loading of traffic throughout its design life span. A field measurement device, referred to as a pavement integrity scanner (PiScanner), was developed for use in quality control and quality assurance programs for concrete layers of pavement systems. PiScanner is based on the enhanced resonance search (ERS) technique, which evaluates the vertical variation of elastic modulus or compressive strength of the concrete layer in pavement systems. This information can be used in the construction period of a concrete pavement to evaluate the curing process of near-surface materials. In the implementation of the PiScanner, two design schemes were incorporated: a dedicated hardware device to perform measurements and an automated analysis algorithm to minimize user expertise required for analysis. The resulting PiScanner allows ERS measurements to be performed in about 2 min with complete analysis of the measurements in about 3 min. Two field investigations were performed on a concrete test slab and at an express highway to prove the reliability and feasibility of PiScanner. Vertical variations of elastic modulus of concrete layer were successfully obtained by PiScanner.