Finite element modeling of thin fiber reinforced concrete pavements

Abstract

Thin concrete pavement is an economical option for low and moderate traffic roads, where thethickness of concrete slab varies from 4-inch to 6-inch. In conventional concrete pavement, dowel bars are used to increase load transfer efficiency (LTE) and mitigate transverse joint faulting. However, dowel bars cannot be accommodated in the thin concrete pavement due to insufficient clear cover. For such pavements, structural fibers are a good option for increasing joint performance or load transfer efficiency, as well as reducing faulting. However, only limited studies are available in understanding the contribution of structural fibers to the benefits of joint performance and the behavior of fibers during the transfer of loads across the joint. In this study, finite element analysis of the thin fiber reinforced concrete (FRC) pavement was performed. A six-slab model was developed with a granular aggregate layer, replicating the actual field conditions. The effect of concrete and base layer structure, material properties, traffic and environmental loads, and joint stiffness on the transverse joint performance and critical stresses were studied. It was found that around 40% of the wheel load is transferred through the pavement foundation and the rest through the aggregate interlocking and fibers’ lateral stiffness. Critical stresses for the fatigue cracks along the wheel path were also determined in this study. This study concluded the minimum required lateral stiffness of the structural fibers for a desired level of joint performance as a function of the pavement structure.