Geotextile selection for roads typically comes down to weight, strength and opening size — but those three numbers must be matched to the actual function the geotextile is doing on that layer.
For separation between sub-base and soft sub-grade: target 200 to 300 g/m² Non Woven Geo Textile with adequate CBR puncture resistance for the aggregate gradation overlying. Higher weight for sharp angular aggregate.
For filtration behind retaining walls or in sub-surface drains: target 150 to 250 g/m² with apparent opening size matched to the surrounding soil grain size (typically 75 to 150 microns for typical Indian alluvial soils).
For stabilisation of weak sub-grade: combine geotextile with geogrid for full reinforcement performance — geotextile alone provides limited mechanical reinforcement.
For protection of geomembrane in landfill caps or canal lining: 400 to 600 g/m² with high CBR puncture resistance.
For erosion control on slopes and embankments: combine with coir blanket or HDPE geomat for vegetation establishment.
MORTH Section 700 and IRC: SP: 59 cover geosynthetic use in road construction with standard test methods. Auroguard supplies Non Woven Geo Textile with test certificates referenced to these standards.