Moisture changes in expansive subgrades beneath the pavements cause movements, which are reflected as changes in the surface profile of the pavement. A design approach that reduces this change in moisture to a minimum will keep the surface profile change to an acceptable level. One technique, which has been accepted as part of standard practice by VicRoads, is the use of vertical moisture barriers (VMBs) installed at the edge of the sealed pavement. This paper provides a guideline for choosing the location of VMBs by addressing the important factors of soil type, soil behaviour and microclimate. Furthermore, power spectral density analysis of road profilometer data is used to refine the choice of pavement sections needing VMBs. This is a development that contributes to the economic use of the VMB for major highway systems. (A)
Samenvatting