A Review on Improvement of Subgrade Soil Using Coir Geotextiles

India has one of the largest road networks in the world, aggregating to about 33 lakh km at present. However many of the existing roads are becoming structurally inadequate because of the rapid growth in traffic volume and axle loading. At locations with adequate subgrade bearing capacity/CBR value, a layer of suitable granular material can improve the bearing capacity to carry the expected traffic load. But at sites with CBR less than 2%, problems of shear failure and excessive rutting are frequently encountered. The ground improvement alternatives such as excavation and replacement of unsuitable material, deep compaction, chemical stabilization, pre loading and polymeric geosynthetics etc., are often used at such sites. The cost of these processes as well as virgin material involved is usually high and as such they are yet to be commonly used in developing nations like India. In this situation natural fiber products hold promise for rural road construction over soft clay. The Review has been made on the performance coir geotextile as a reinforcement in various soil conditions.