Concrete pavements in large part are designed as flat slabs although in the past they have included thickened edges. Thickened edge slabs are used today where positive load transfer for some reason cannot be provided. The Rated Axle Load Enhancement (RALE) system concept involves the use of longitudinal stems to stiffen the concrete slab. A close analogy is that of a wide double or quadruple "T" beam. The stems may be rectangular or trapezoidal.

In this study, RALE systems with two and four rectangular stems as well as plain concrete slabs were analyzed using the finite element method (FEM). The stresses in different pavement structures under wheel and thermal load were compared. The issue of curling/warping associated surface smoothness was also addressed. It is predicted that the RALE system would perform better than conventional flat slabs, especially for cases where thermal load is involved, for cases where thermal load is involved. In such cases, the RALE with four stems is better than the RALE with two stems.

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concrete pavement, finite element method, thermal stress, SPR-2160

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Performing Organization

Joint Transportation Research Program

Publisher Place

West Lafayette, IN

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