OWNER:
Mississippi Department of Transportation
401 North West Street
Jackson, MS 39201

PROJECT ENGINEER:
Tanner Construction Company
677 Pecan Grove Road
Ellisville, MS 39437

SEGMENTAL WALL DESIGN/BUILD COMPANY:
Synergy Earth Systems, LLC.
26240 Equity Drive
Daphne, AL 36526

There is a stretch of I-59 in Laurel, MS that has a series of sharp curves. Over the years, this winding section of highway has seen its share of accidents. To alleviate the sharp curves, this section of I-59 was redesigned. The new highway design called for a segmental block wall to be used beneath one of the bridge abutments and along the side of the highway. The Mississippi DOT (MDOT) saw the aesthetic and economic benefits of using a segmental block wall system over other wall types. MDOT also selected a section of highway near the segmental block wall that would utilize a wire faced temporary wall system.

Synergy was selected by Tanner Construction to provide design/build services related to the segmental block and temporary wire faced walls on this project. During the design of the segmental block wall, Synergy was able to work with Tanner Construction to incorporate a backfill material that was much more cost effective that the standard #57 Stone used on most DOT projects. This allowed for some cost savings and reduced the chance of delays due to a lack of #57 Stone being available in the area. Another design item that Synergy helped out with related to the soil behind the backwall of the bridge abutment by the block wall. MDOT had a concern about the possibility of the soil behind the abutment backwall pushing enough to cause the drilled shafts beneath the abutment to move. Synergy proposed the use of a welded wire form pressure relief wall behind the abutment backwall to keep the soil pressures off of it. This proposal was accepted by MDOT and incorporated into the design drawings produced by Synergy. The final wall drawings called for about 10,000 sf of segmental block wall and about 1,500 sf of wire faced walls. The first phase of construction was completed in the fall of ’07 and the second phase is expected to start and finish in the Fall of ’08