Vietnam National Expressway Soft Soil Subgrade Project (Polyester Warp-knitted PET Geogrid)
Vietnam National Expressway Soft Soil Subgrade Project (Polyester Warp-knitted PET Geogrid)
Project Overview: This is a national expressway project in Vietnam. The site features alluvial soft soil subgrade with a high groundwater table and heavy rainfall in rainy seasons. The originally designed subgrade was vulnerable to differential settlement, pavement rutting, and intermixing between subgrade fill and soft soil.
Project Challenges: Deep soft soil strata and high groundwater level lead to continuous settlement under cyclic vehicle loads. A three-in-one solution combining reinforcement, separation and filtration is required.
Selected Product: Composite warp-knitted polyester geogrid (400kN/m biaxial PET geogrid laminated with 100g staple fiber geotextile), total area: 300,000 ㎡.
Construction Solution: After soft ground treatment, the composite geogrid is laid at the bottom of the subgrade, beneath the subgrade cushion layer. It evenly distributes vehicle loads and blocks soft soil from intruding upward into the crushed stone layer.
Project Results: Eliminates subgrade differential settlement and pavement rutting; reduces consumption of crushed stone aggregates. The material passed third-party ASTM creep testing. Zero quality incidents occurred during construction and the construction period was shortened.
