Greenheart Timber Strip Reinforcement for Reinforced Soil Retaining Walls

Abstract

This article presents the result of investigating the feasibility of using greenheart timber strips as reinforcement for reinforced soil retaining walls in Guyana. The work is intended to assess the cost economics between greenheart timber strips and geogrids as reinforcements. Medium grained river sand is used as fill material in reinforced soil retaining wall designs. The interfacial friction between greenheart timber and fill material is determined by the laboratory pullout test. The designs of reinforced soil retaining wall revealed that Greenheart timber strips of 350mm width and 25mm thickness are sufficient to reinforce retaining walls with backfill of heights 4m and 6m, while greenheart timber strips of 350mm width and 50mm thickness are sufficient to reinforce retaining walls with backfill of heights 8m and 10m. It is observed that as height of retaining wall increases from 2m to 10m, the percentage cost saving of using greenheart timber strips as compared with geogrids, increases from 10% to 24%.