Rigid‐Pavement Evaluation Using NDT—Case Study

Abstract

A case study of a highway rigid‐pavement evaluation using deflection‐based NDT is presented. The test section consists of 280 mm of concrete, 150 mm of cement‐stabilized base, and 150 mm of gravelly sand on a clayey subgrade. Deflection bowls are measured using DYNATEST FWD at three different locations: (1) At the interior of the slab; (2) along the free edge; and (3) at transverse joints and cracks. The load‐deformation characteristics of the pavement materials are evaluated using the MODULUS back‐calculation procedure and the following models for pavement representation: (1) The three‐layer system; (2) the Hogg model; and (3) the Hertz‐Westergaard model. The main conclusions from the analyses are: (1) The deflection basin of a concrete pavement with a stabilized base on a subgrade seems to be better described by a composite plate on a subgrade rather than by a plate on a composite subgrade; and (2) the modulus of subgrade reaction seems to depend on the load location at the interior of the slab or near the free edge.