Construction of Reinforced Earth® Wall at Rara Airport, Nepal

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

241.4m

2025

3700 sq.m

19.85m

Rara Airport, located in the remote mountainous region of northwestern Nepal, required critical slope stabilization and runway safety improvements at the northern end of the air field. A steep slope immediately adjacent to the paved runway restricted the provision of an adequate Runway Safety Area (RSA), creating operational and safety concerns. In addition, the area was prone to soil instability and landslide activity, necessitating the construction of a high retaining structure.

The project called for a retaining wall with a maximum height of 19.85 m to create the required clear space around the runway while ensuring long-term slope stability.

To address these challenges, the client engaged Geoquest India to develop a sustainable alternative. Following a detailed assessment of site conditions, terrain constraints, and locally available resources, Geoquest recommended the ArmaStone® reinforced soil wall system. The solution provided a cost-effective, durable, and technically robust retaining structure capable of stabilizing the slide-prone slope while meeting the airport’s safety and operational requirements.

Manual Dismantling of Existing Gabions: Time-consuming and labor-intensive removal of previously constructed gabion structures.

Remote Site Logistics: Challenges in mobilizing construction materials, equipment, and machinery to the project location.

Airport Operational Constraints: Execution restricted by ongoing airport flight operations and safety requirements.

High-Altitude & Difficult Terrain: Harsh weather, rugged terrain, and high-altitude conditions impacted workforce productivity and equipment movement.

Short Working Season: Limited construction window of only about four months annually due to the site’s remote location and climatic conditions.

Geoquest India proposed an ArmaStone® Reinforced Soil Structure with a steep 70° face inclination to provide a stable and space-efficient retaining solution. The
structure consists of a mechanically stabilized soil mass constructed in compacted layers and reinforced with 50 mm wide High Adherence GeoStrap® in the top layers and 50 mm wide smooth GeoStrap® coated with Linear Low-Density Polyethylene (LLDPE) in the main reinforced zone. These reinforcement elements are mechanically connected to a flexible galvanized steel mesh facing, ensuring structural integrity and adaptability.

Owing to the considerable retained height, the wall was designed in a two-tier configuration, incorporating special compressible galvanized steel mesh panels to accommodate differential settlement and enhance overall flexibility. To effectively manage seepage and groundwater, a high-transmittivity Draintube™ multi-linear drainage geocomposite was installed throughout the hill profile and across the foundation bed, providing efficient subsurface drainage and reducing hydrostatic pressure behind the structure.