Geoquest India (formerly known as Reinforced Earth India Pvt. Ltd.)

202m

June 2020 – May 2022

5667 sq.m

46.61m

Several years ago, a municipal waste landfill site was selected in the hills near Kathmandu, Nepal. The landfill site was not very organised and the waste materials, especially the leachate, was contaminating a river in the valley below. Therefore, the owner proposed constructing a new dumping site at Bancharedanda in Nuwakot District. To restrict the waste and leachate within the designated area, a retaining structure needed to be constructed. Considering the large amount of solid waste in Kathmandu city, the maximum height of the retaining embankment has been considered as 44m. 25 meters were proposed for the first phase of
construction. Primarily, a conventional earthen embankment was proposed with a significant base width, which was not available in the hilly region. A vertical retaining structure was required. Gabion faced retaining structure was rejected by the project owner as the gabion was not durable enough. Therefore, Geoquest India was contacted for an appropriate and durable solution.

• Tall retaining structure with a minimum requirement of base width.
• TerraFlow® was used as a vertical geocomposite drain behind the concrete facia panels. Redundant“geocomposite drain” behind the concrete facia panels.
• TerraLine® was used as geosynthetic clay liner to create an impermeable layer at each level of berm. It was also used along with alkali sealant at the panel joints on the waste fill side to prevent leachate from entering the Reinforced Earth® zone.
• TerraDrain® was used as horizontal geocomposite drainage at each level of berm as a seamless drainage bay.
• A stable retaining structure with adequate durability for proper waste management.
•  Rapid construction with premium engineering quality.
• Interface with leachate collection system.
• Compressible panels to enhance flexibility of the wall.
• Watertight to prevent ingress of leachate and hazardous liquids.

Geoquest India proposed Reinforced Earth® Structure comprising the construction of an internally stabilized soil mass, built in layers and compacted with specified fill materials with top layers of 50mm wide High Adherence GeoStrap® and 50mm wide GeoStrap® coated with Linear Low-Density Polyethylene (LLDPE) as soil reinforcing structural elements of designated grades and design strengths connected through a mechanical connection system. TerraTee® concrete panels with GeoCore mechanical connectors were used. Being a tall structure, special compressible-type panels were used to allow enhanced flexibility in the wall.