The State of Florida has only one underground roadway. The Kinney Tunnel under the New River in Fort Lauderdale was built in 1960. In 1986, it was named to honor Henry E. Kinney, the respected journalist who was the Broward Edition Bureau Chief for the Miami Herald. The tunnel carries four lanes of traffic and has elevated pedestrian sidewalks along the outer walls. The north and southbound traffic lanes are separated by a central support wall that runs the length of the tunnel. Several construction joints run up the walls and connect across the ceiling and floor. The interior is lined with four inch square ceramic tiles.
Recently, the Florida D.O.T. found that water was leaking through a few of the joints. They contacted Prime Resins looking for a repair material and an experienced contractor. Because the joints are subject to movement, they needed a material that would remain flexible. Prime Resins suggested Prime-Flex 900 LVSF, a low viscosity, solvent free, hydrophilic polyurethane grout, and recommended that they contact Dennis Hoover of Pneumatic Restorations South to make the repairs. Dennis bid on the job and the Florida Department of Transportation awarded the repair work to Pneumatic Restorations South.
To inject the grout deep into the joints, Dennis used an offset drilling technique. Starting approximately eight inches from the side of the joint, he drilled at a 45° angle towards the joint. The drilled hole intersected the joint at a depth of approximately eight inches. To inject behind the wall, he drilled at a 45° angle downward through the sidewalk and through the side of the joint. He carefully removed the four inch square tile at each drilled location up the walls and across the ceiling. He drilled every eighteen inches along the joint in the side walls. Over the ceiling, he drilled about every forty inches. At the center support wall, he again drilled at a 45° angle upward through the wall and into the joint.
During the injection of the joints, a few leaks were found near some intruding pipes. The most serious leaks were first plugged with oakum, a dry, rope-like material. Injection holes were drilled at 45° angles into voids around the pipes. Prime-Flex 900 LVSF was used to repair these leaks as well. After injection was complete and the leaks were stopped, the ceramic tiles were bonded back into place making the repair nearly invisible.
Several weeks after the repair was completed, only one new leak was found. It was repaired in one night by injecting a ten foot long section of the joint with five gallons of Prime-Flex 900 LVSF.
