Application of Non-woven Polyester Geotextile for Soil Improvement in Pavements

Abstract

The performance of flexible pavements are greatly affected by the type of subgrade, sub-base, and base course materials; the most important of these are the properties of soil subgrade, as it serves as the foundation for pavement. In India, around 8 lakh km2 area is covered with poor subgrade soil covering central, some parts of southern region, and along the coastline. The pavement constructed over such soils will lead to greater thickness requirement, and it will also fail prematurely under heavy wheel load. In order to overcome such untoward situation, some ground improvement technique has to be adopted. This paper presents the effect of including non-woven polyester geotextile on the strength behavior of weak subgrade soil. The geotextile sheets are placed in single and multiple layers at various depths of soil subgrade and thereby determination of optimum combination and optimum position of reinforcement based on the California bearing ratio results are done. Greater improvement in CBR is observed for soil samples reinforced with geotextile in upper layers of subgrade as compared to lower ones with a maximum increase of 70% corresponding to double layer geotextile at 0.2 and 0.4 H depth from top of mold. It can be concluded that geotextile sheets can be considered as a good earth reinforcement material.