TDOT contract crews will begin work later this week to stabilize a section of U.S. 127 (Signal Mountain Boulevard) near log mile 15.97. Beginning on Thursday, crews from GeoStabilization International, LLC (GSI) will start work to make permanent repairs to an area of the roadway that has shown signs of instability. Barring unforeseen circumstances, the repairs are expected to take approximately eight weeks to complete. During the repairs, the road will be reduced to one lane and traffic will be controlled with a temporary signal.
TDOT regional maintenance crews regularly monitor U.S. 127 on Signal Mountain, and if they find an area of concern, they contact TDOT’s geotechnical engineers to come in and assess it for possible repairs. During a recent routine inspection by TDOT maintenance personnel, they found signs that the location near log mile 15.97 might require more in-depth repairs than those done under regular maintenance. Geotechnical engineers assessed the site and came up with a repair plan, which is what will be implemented with these repairs. The work will be done using crews from GSI under a statewide on-call maintenance contract for soil nailing and slope stabilization.
During the work, loose material will be removed from the area and the slope will be stabilized using soil nailing. Soil nailing is an on-site soil reinforcement technique where soil nails are placed into the natural ground at relatively close spacing to increase the strength of the soil mass. As the bars are being drilled, grout is inserted into the hole to ensure that the soil nail stays put. A steel reinforced concrete wall will be constructed that encompasses the soil nails to form a retaining structure along with means to drain water from the slope behind the wall. The upper portion of the retaining structure will be backfilled with new material and the roadway will be rebuilt.
Message boards will be placed at each end of the work zone notifying the public of the one-lane condition. Those who regularly travel on U.S. 127 should anticipate the extra time that it will take to get through the work zone.