One of the most recently developed pieces of GPR equipment emerging in today’s market is the multi-array (fitted with multiple antennae) bridge inspection unit (BIU). Although typically linked to bridge inspections, this device can map the arrangement and condition of any horizontal structure, providing specific information on reinforcement cover depth, delamination, voiding, and relative moisture content. Its use does not have to be limited to concrete either. The technology allows for scanning through asphalt and other masonry types, such as brick and stone pavers; however, it was specifically developed with structural health assessments in mind.
This system is comprised of multiple antenna frequencies, instead of using the traditional individually mounted antenna set up, for data collection. The antenna array can provide a highly detailed 3D underground tomography of the mapped surface. This greater detail enables a more accurate diagnosis of a structure’s thickness, reinforcement placement, retained moisture, and levels of deterioration, most commonly associated with moisture or delaminations. As with all NDT techniques, the use of this equipment must be combined with additional investigation techniques to corroborate the data and verify the results.
The design of the system allows for rapid, accurate, high-resolution data to be collected at speeds of up to 12 miles per hour. When comparing this data to vehicle-mounted air-coupled (not in contact with the surface) GPR arrays, which gather data at higher speeds, the resolution is far more defined. This is due to intimate contact with the surface and a high density of data
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Civil engineering is a professional engineering discipline that deals with the design, construction, and maintenance of the physical and naturally built environment, including works like roads, bridges, canals, dams, and buildings..........