In the winter of 2015, the private neighborhood of Lost Rabbit in Madison, Mississippi was preparing for a new phase in their development. This new phase of construction would include a man-made canal that would lead directly into the Ross Barnett Reservoir, a 33,000-acre lake situated in the Pearl River Valley.

In order to connect the new phase of the development with the existing neighborhood, a bridge over the canal would be required. The new bridge would be supported on abutment walls with wingwall sections to support the embankment approaches to the bridge. Acting on a referral from another construction company familiar with the Redi-Rock retaining wall system, the general contractor contacted MMC Materials in Jackson to determine if the Redi-Rock system could provide a less costly solution for the wingwall sections.

JC Hines and Associates quickly went to work to help MMC find a solution for their customer. The low shear strength and highly expansive clay soils at the bridge location created some significant challenges for the wingwall design. Given the overall height of the walls, it was determined that the most efficient wingwall design would be delivered by the Redi-Rock Positive Connection (PC) system.

The Redi-Rock PC system utilizes 12-inch strips of geogrid reinforcement to anchor each individual block unit. Designed as a mechanically stabilized earth (MSE) wall system, the reinforced zone immediately behind the block units was backfilled with a coarse sand fill to provide sufficient shear strength for the wall design and to allow adequate drainage behind the wall in this critical application. To mitigate the effects of the expansive clay soil, the entire Redi-Rock wall structure would be placed on a soldier pile supported reinforced concrete foundation. Installation moved quickly and the entire bridge superstructure was completed in less than a month

“This was an interesting project for us because it was our first Redi-Rock job with a wing wall in a water application and it was such a smooth process,” said Andrew Lester of MMC Materials.

The Redi-Rock Ledgestone texture blocks were manufactured by MMC Materials in Jackson, Mississippi.