TEXTILES.ORG
Introduction
The main objectives of this project were to build a retaining wall to support a road and to create more room for the width of the road, especially at the turn.
Potential problems
A primary goal was the repairing and widening of an existing 4m- (13ft)-wide road to 5m (15.5ft). In addition, the roadbed had sustained severe erosion damage at the steep, unstable embankment adjacent to the road.
Geosynthetic solutions
The first order of business was the construction of a retaining wall by stacking geocell panels to increase road width and eliminate embankment erosion.
Unstable soil and vegetation was cleared from the embankment. Then a soil base was leveled and pylons were inserted in the base 2m (5.75ft) deep. Two pylons were placed per geocell panel, with each panel measuring 2.56m x 1.6m (8.5ft x 5.25ft). The pylons were 6-in. PVC pipe filled with concrete and rebar frame.
The first layer of the 6-in. geocellular confinement material was filled with concrete. Subsequent layers were filled with on-site soil and compacted until level with the road surface (3m/10ft). Perforated pipe with a nonwoven geotextile covering was also used during construction for drainage.
The top layer was finished with road fill and guard rails were set in concrete within the geocells. Upon completion, the wall area measured 45m (150ft) long and 3m (10ft) high.
A six-man crew, with loader and operator, took five working days to complete this job.