Studies on geosynthetic-reinforced road pavement structures

Many of the pavement structures fail well before their design life owing to the poor quality of construction materials, inadequate compaction, inadequate preparation of the subgrade, overloading, etc. Two options are available to improve the longevity of the pavement. The first option is by increasing the thickness of different pavement layers and the other option is by increasing the rigidity of the layers within the system so as to reduce the stresses transferred to the lower layers. Of these two methods it has been widely observed that increasing the strength and rigidity of the pavement layers is a more efficient method to lower the stresses on the pavement layers thereby increasing the life of the pavement. In the present research work, the improvement in the strength and stiffness of the subbase layer in a flexible pavement system through the use of geosynthetic layers was investigated by conducting field plate load tests and a series of laboratory plate load tests. The improvement in the strength of the pavement is reflected by the increase in modulus of the section reinforced with geosynthetic layers. This paper will describe the field and laboratory tests, interpretation of the data from these tests, and the application of this data for design of flexible pavements and their economic analyses.