Mechanistic Approach for Fiber-Reinforced Flexible Pavements

The present study investigates the benefits of reinforcing the subgrade soils in flexible pavements. Three types of Soils A, B, and C, and one type of polypropylene fiber having aspect ratios of 50, 84, and 100 were selected. The California bearing ratio CBR and unconfined compressive strength tests were conducted on unreinforced and reinforced soils. The optimum quantity of fibers was decided based on CBR, modulus of elasticity Ei and failure stress. The static triaxial tests were conducted on unreinforced and reinforced soils as well as on other pavement layers at a confining pressure of 40 kPa. These stress-strain data were used as input parameters for evaluating the vertical compressive strain at the top of subgrade soils using elastoplastic finite-element analysis. This vertical compressive strain at the top of unreinforced and reinforced subgrade soils was used for estimating the improvement in service life of the pavement or reduction in thicknesses of different layers for the same service life due to reinforcing the subgrade soils.