Shear Wave Method for Concrete Pavement Diagnostics

Abstract

Field trials involving typical pavement constructability and rehabilitation issues at the Federal Aviation Administration’s National Airport Pavement Test Facility, the Minnesota Road Research Project, and various in service pavements using MIRA were verified. The trials indicate that, while the device is a useful portable pavement diagnostic alternative capable of consistent thickness measurement, reinforcement location, and distress evaluation, significant efforts and user expertise are required for measurement and data interpretation of large scale applications. Thus, a couple productive, objective signal interpretation methods are presented for automated analysis of reinforcement location in continuously reinforced concrete pavement as well as an initial distress indicator using two-dimensional ultrasonic signature analysis. This type of automation for multiple applications shows promise for the use of ultrasonic tomography to improve large scale pavement quality assurance, quality control, and rehabilitation projects in the future. Innovative imaging methods such as synthetic aperture focusing technique panoramic reconstructions and synthetic aperture focusing technique three-dimensional visualizations were also introduced to improve the ability to obtain relational information when dealing with larger scanned areas. Ultrasonic tomography is shown to be an accurate, reliable, and convenient alternative/supplement to traditional techniques or can be used to replace or reduce the need for forensic methods such as coring.