Stiffness and Thickness Measurement of HMA Pavement with Flying Microphone Arrays: Fid-Bau Portal

Stiffness and Thickness Measurement of HMA Pavement with Flying Microphone Arrays

Park, Choon / Starkhammar, Josefin / Ryden, Nils

In January 2020, the Minnesota Department of Transportation (MnDOT) launched a project to build a seismic system that one can routinely use in the field for quality management of Hot Mix Asphalt (HMA) pavement. The system measures the shear-wave velocity (Vs) and thickness of the pavement. When fully completed, it will be a 2D receiver-array system consisting of four (4) 1D arrays arranged transversely to measure a certain width of pavement with a high-spatial resolution (e.g., 2 ft × 1 ft). The system can be easily harnessed on a bicycle rack on the back of a car, which can travel at a speed of 10–30 MPH making rolling measurements. The on-board GPS and IR sensors record the location and temperature data for geo-referencing and temperature-referencing of the final results. The on-board software package analyzes incoming data in a fully automated mode to display results on a computer screen almost in real time. At the time of paper preparation, building and testing of the 1D 16-channel MEMS microphone array system has been completed. It includes a rolling impact source, recording device, and the on-board software package. The field test performed along a 1.2-km HMA road produced highly reasonable Vs and H values.