Rapid condition evaluation of concrete pavement with automated acoustic scanning system

The paper describes a practical and rapid automatic crack evaluation system (ACES). It is a newly developed automated multichannel rapid automatic impact system for rapid evaluation of bridge decks based on impact echo test using a rolling hammers impactor and air-coupled sensing with high spatial resolution providing high impact power for deep delamination and consistent scan resolution regardless of speed. The researchers have developed rapid ACES approach using a high-speed stress wave generator to show pavement deficiencies. The guided wave were used to identify internal and surface vertical cracks. The resonance vibrations by generating stress waves (called as impact echo) are used to identify the internal horizontal crack and its delamination. The RPI mechanical waves produce a vibrational resonance through the thickness of the pavement, which can be detected by using non-contact micro-electro-mechanical system (MEMs) sensors for high sensitivity and high speed data collection[1]. The acquired signals will be transferred and stored in a computer with software that can develop signal processing and create identification algorithms. Its results identified the peak frequencies on a short time Fourier transform (STFT) spectrogram in the frequency range 0.5-6 kHz. Both results were verified on a concrete slab with artificial delaminations in the laboratory. The results were compared to both the air-coupled manual impact echo approach and 3D ultrasonic tomography (MIRA) results. A positioning system is integrated to automatically track test positions and save time in documenting and identifying test results and position information. Rapid condition evaluation of concrete runway pavement helped the strategic evaluation and implementation of a proper pavement maintenance and replacement plan.