Properties of Modern Flowable Fill Incorporating Rapid-Setting Cements: Laboratory and Field Studies of Dry Placement Method

Timely maintenance and rehabilitation is critical to ensuring the long-term sustainability of transportation infrastructure. Full-depth pavement repairs represent a significant investment of both time and money, but such repairs become necessary where localized pavement failures have occurred as a result of inadequate performance of the underlying support system. Subsurface layers are traditionally repaired using compacted lifts of aggregate. While this approach is relatively inexpensive, it is labor-intensive, time-consuming, and can lead to premature repair failure if the layer is not adequately constructed. Rapid-setting (RS) flowable fill provides a backfilling material option that flows under gravity to fill subsurface voids, self-consolidates, and sets rapidly to facilitate the early placement of surfacing material. The dry placement method is a novel technique in which the blended RS flowable fill is placed in its dry state and water is added without mixing. The performance of three commercially available RS flowable fill materials placed using the dry method was investigated using both laboratory and accelerated full-scale vehicle trafficking. Results from these experiments indicate that reduced repair time and in-place cost, as compared to traditional repair techniques, can be achieved when flowable fill containing RS cement is employed using the dry placement method.