Thermal Stresses in Asphalt Overlay Paved on Existing Cement Concrete Pavements (Ⅲ):Thermal Stresses Analysis and Local Treatment Effects

Abstract:

The thermal stresses in asphalt overlay paved on existing cement concrete pavement slabs are systematically discussed, and the effects of void underneath cement concrete pavement slabs and local treatment near joint sides on thermal stresses are analyzed.It is concluded that the most efficient measure in practice to reduce the thermal stresses in asphalt overlay is to place an interlayer between asphalt overlay and existing cement concrete pavement slabs on joints area with low shearing modulus and Possion’s ratio large enough (close to 0.5), in other words, the tangential stiffness factor λu shall be less than 1/20 and the normal stiffness factor λv shall be greater than 1/3, and the placing width of interlayer on one side of joint shall be 0.3~0.4 m.

Key words:road engineering; asphalt overlay; thermal stress; void underneath pavement slab; local treatment