An evaluation of the northbound bridge approach and the abutment wall of (Combs-Hehl) bridge on I-275 in Kenton County was conducted in September 2007. The inspection consisted of using ground penetrating radar to look for potential voids beneath the concrete approach slab and a video camera inspection to inspect the void space beneath the pier cap/concrete beam in front of the abutment wall.

Results of field testing and recommendations:

A possible void approximately 1-2 inches in depth resides under the approach slab approximately 105 feet before the bridge abutment in the fast lane. It is recommended that this section be filled with cement grout. The camera inspection beneath the pier cap/concrete beam indicates that approximately 447 cubic feet of material has been displaced. It is suggested that the void space be filled with either cement grout or crushed aggregate. It is also recommended that the water eroding around the side of the abutment wall be diverted away from the bridge embankment.

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