Stress Analysis of Small Concrete Slabs on Grade

Abstract

Stress conditions in precast airfield concrete pavements are analyzed using the finite element method. The pavements analyzed were small concrete slabs connected at the joints by load‐transfer devices. The slabs were square‐shaped with dimensions varying from 3 ft (0.92 m) and up and slab thicknesses varied from 3–12 in. (11.8–47.2 cm). In contrast to the known fact that the installation of dowel bars and keyed joints in conventional highway and airfield concrete pavements can effectively reduce stresses in concrete slabs, it was found that stresses in small concrete slabs may actually be increased, depending on the loading position. The stresses in the small concrete slabs are increased and the deflections are decreased with increasing slab size. These changes cease when the slab size is increased beyond a certain value. This value increases with increasing slab rigidity, tire contact area, and gear spacing for multiple wheels.