The effectiveness of using a mechanically stabilised layer for unpaved roads in Vietnam: Some case studies

The construction of onshore wind powers requires an access road network, whose pavement design is challenging due to the complexity of ground conditions subjected to heavy vehicles. A thick pavement structure, therefore, is often required following the conventional design method, leading to uneconomic designs and solutions. The use of multi-axial stabilisation geogrids to form a Mechanical Stabilised Layer (MSL) was considered to optimise the pavement structures as well as to reduce material costs, construction time, and carbon footprint of construction activities while maintaining the technical requirements. This paper presents experimental tests conducted in wind power projects in Vietnam to evaluate the pavement performance with and without MSL. A comparison between stabilised and conventional sections is analysed in terms of the modulus of elasticity, rutting depth, and carbon emission reduction. The study results can be applied to pavement design procedures for residential roads, industrial roads, and highway projects.