There is anecdotal evidence that pavement maintenance patches fail within a few years and research was undertaken to develop a framework for predicting the life of patches to enable asset managers to choose the right treatment to give the life required with the lowest whole-of-life costs.
A total of 12 maintenance patches were constructed consisting of cement stabilisation (two cement contents 1.5 percent and 3 percent); mill and asphaltic concrete inlay; and full depth granular reconstruction replicated on three different state highways.
These maintenance patches were treated as full pavement renewals in terms of testing and investigation prior to their construction.
This information allowed basic pavement characteristics, such as the impact of traffic; pavement depth (adequate, inadequate or very inadequate); aggregate quality (good, average or poor); and pavement deflection (high, medium or low), to be determined prior to patching.
The patches were monitored for three years and during this period most failed.
The monitoring allowed the creation of algorithms based on the basic pavement characteristics to predict the life of the patch treatments.
A tool was developed to allow designers and asset managers to make informed choices on the type of patch treatment based on predicted life, and so prevent early failure of the patches.
Keywords: maintenance, patches, potholes.