2019 Partner Winner
GeoProfessional Innovation Corporation (GPI): Almon Street & Ground Penetrating Radar
- Problem: Almon Street in Moscow was at one time paved with Portland Cement Concrete (PCC) pavement. Through many years of roadway maintenance and utility repair, this road segment has received multiple hot mix asphalt (HMA) overlays and the underlying PCC pavement has been sawcut and patched with HMA pavement in various locations. This has created a random patchwork of HMA and PCC pavement sections throughout the roadway alignment. The City sought to evaluate various pavement rehabilitation or reconstruction alternatives, and needed information about the extents of HMA thickness atop PCC pavement from which to base design and construction cost estimates.
- Solution: GPI proposed to use ground penetrating radar (GPR) in combination with localized coring to evaluate existing pavement section configurations across the alignment.
- Labor, Equipment, Materials: Geophysical exploration and coring required a crew of 3 people, over the span of a single day, to collect the required field data. GPR survey was conducted using Geophysical Survey Systems, Inc. (GSSI) SlR3000 control units with a 1.6 GHz antenna and a 2.6 GHz antenna. Coring utilized a trailer-mounted core drill and 6-inch diameter diamond core bit to penetrate the asphalt/concrete pavement and expose the underlying subgrade.
- Expenses: Field exploration equipment and labor expense for GPR survey cost $5,500.
- Savings/Benefit: The amount of data provided by the GPR survey was substantially more than could be provided by traditional coring or drilling alone. This data helped the City of Moscow evaluate various alternatives for reconstruction or rehabilitation. Also, this non-invasive technology reduced disturbance to the road surface and the travelling public to a handful of locations over a handful of hours.
