Intrinsic roughness mitigation of pavements on expansive soils –an analytic investigation

Pavements resting on active clays are exposed to uneven heaving and shrinking of their bottom boundary. This paper investigated the inherent ability of pavements to mitigate such underlying (core) roughness. The problem is addressed and analyzed with an analytic model. It is found that the combined thicknesses of all inert pavement layers govern this smoothing feature. Core wavelengths that are much larger compared to the aforementioned thickness are essentially mirrored at the surface. Conversely, core wavelengths shorter than the system’s thickness are attenuated. The information included in this work can serve as an additional (and rational) decision basis for the design and evaluation of pavements on expansive soils.