THE APPLICATION AND VALIDATION OF AN ANALYTICAL METHOD IN THE STRUCTURAL REHABILITATION OF A CRACKED RIGID PAVEMENT

Abstract

The use of high alkali cement together with aggregates rich in silica to construct a jointed unreinforced concrete pavement without dowels resulted in a chemical reaction that caused microscopic cracking. This cracking not only reduced the stiffness of the slab but also reduced the strength of the subbase so that structural cracking developed under traffic loading. The visual assessment of the structural condition of the pavement was based on a load transfer constant which in turn correlated with deflections and relative vertical movements at the joints. In order to relate the visual condition to pavement response and eventually performance, an analytical model was used to calculate pavement response in terms of vertical movement and deflections. Experimental overlay sections, using Portland cement concrete, continuously graded crushed stone and asphaltic concrete, were constructed to calibrate the analytical model and these sections are being trafficked by road users in addition to a mobile accelerated traffic simulator, the Heavy Vehicle Simulator, to evaluate the relative performance of each section. This paper discusses the findings on some of the concrete overlay sections and the data is extrapolated to include preliminary predictions of the performance of those overlays that have not yet been tested by the HVS.