Gravix Gravity Wall Systems
38.2 Ft. Tall, 283 Ft. Long, 8,769 Sq. Ft. Face Area
The state of Georgia wanted to improve the traffic flow and aesthetics in front of the capitol and chose to construct an approximately 40 foot tall retaining wall. The wall is in front of the capitol and helps place the capitol distinctly back from the main artery through Atlanta which is the I-75/I-85 connector.
The retaining wall chosen was Gravix. Gravix is a true gravity retaining wall system and complements the aesthetics and stability worthy of a capitol building. The confines of the location due to excavation, utilities and tight working conditions along with the cost of select backfill prevented using a conventional MSE wall. Gravix is a fairly new retaining wall system but is quickly becoming a good alternative being 100% precast concrete, having one of the longest life expectancies as well as fast modular construction.
Another interesting facet of the Gravix structure was the geotechnical engineer on the project estimated 3 to 12 inches of settlement due to a poor foundation. Therefore, the Gravix retaining wall was constructed up to the bottom of the Leveling unit which is directly beneath the integrated TL-4 Traffic Barrier unit at the top of the wall.
The Leveling unit varies in height and slope angle to keep the Traffic Barrier at the prescribed varying roadway elevation. The wall was allowed to settle out over time with survey monitoring performed until the geotechnical engineer approved the settlement had subsided. Then a survey was made of the top of wall and Leveling units cast accordingly so the Traffic Barrier met the vertical and horizontal roadway curvature. As much as 3 inches of settlement was observed which included differential settlement between adjacent stacked columns of Gravix units. The Gravix units are 8’ wide with a ¾” gap between each adjacent precast unit and constructed on a non reinforced leveling pad allowing differential settlement to occur with essentially a construction joint every 8 feet along the length of wall. By the way, the existing retaining wall continues to be survey monitored for documentation on performance of the 40 feet tall Gravix retaining wall.