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This article investigates the effectiveness of different mathematical methods in describing the three‐dimensional surface texture of Portland cement concrete (PCC) pavements. Ten PCC field cores of varying surface textures were included in the analysis. X‐ray Computed Tomography (CT) was used to scan the upper portion of these cores, resulting in a stack of two‐dimensional grayscale images. Image processing techniques were utilized to isolate the void pixels from the solid pixels and reconstruct the three‐dimensional surface topography. The resulting three‐dimensional surfaces were reduced to two‐dimensional “map of heights” images, whereby the grayscale intensity of each pixel within the image represented the vertical location of the surface at that point with respect to the lowest point on the surface. The “map of heights” images were analyzed using four mathematical methods, namely the Hessian model, the Fast Fourier transform (FFT), the wavelet analysis, and the power spectral density (PSD). Results obtained using these methods were compared to the mean profile depth (MPD) computed in accordance with ASTM E1845.

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In 1998 eight test lanes of ultrathin whitetopping (UTW) were constructed over existing hot-mix asphalt (HMA) pavements at FHWA’s Accelerated Loading Facility (ALF) located at the Turner-Fairbank Highway Research Center in McLean, Virginia. Various combinations of thicknesses, joint spacings, fiber reinforcement, and types of HMA base were used. In spring 2000 the loading experiment of these pavements was completed, and the analysis of behavior and performance was begun. A summary of some of the pavement distresses observed at the ALF is presented, and hypothesized failure mechanisms are identified, providing an addition to the state of the knowledge with respect to the actual life cycle of UTW pavements.