SOIL REINFORCEMENT manufacturer and supplier Huesker has supplied geogrids and a block wall retaining system to combat poor ground at a university sports facility in Charlotte, North Carolina.
Working for Mecklenburg County and Johnson C Smith University, main contractor Crowder Construction Company built an 8000m 2athletics track, an American football field, a 4000-seat grandstand, a press box and classrooms. Design was by consultant Barrier Engineering.
Because the ground on the southern edge of the site consisted of over-saturated alluvium mixed with boulders and fill, a problem compounded by a nearby wetland and creek, a large retaining wall was needed.
The wall is 550m long and varies from 0.6m to 6m high, with a total face area of 2320m2.Before construction began, the ground beneath was reinforced with stone columns capped with a mat. The wall consists of compacted fill reinforced with nearly 7200m 2of Fortrac 80/30-20 and 9200m 2of Fortrac 35/20-20 geogrids up to 6m into the ground, with a design strength of up to 41kN/m. The wall was finished off with Allan Block facing.
A three-tiered cut retaining wall was also built on the northern edge of the site, with temporary support provided by sheet piles. A third wall supporting a pedestrian bridge link to the grandstand was built on the east side of the facility.