Including Bearing Capacity into a Pavement Management System

Resumé

Since three years the Province of Milano is conducting performance surveys of the road network. The survey includes roughness (IRI by ARAN), distress (percentages of cracked and ravelled area, potholes), friction (SFC at 60 km/h by SCRIM) and bearing capacity (deflection by FWD). The purpose of the work is to set up, with the support of the Technical University (Politecnico) of Milano, a specific Pavement Management System (PMS) for the main road network of Province of Milano (covering a total length of 120 km with high AADT values and heavy traffic percentages). The PMS developed two years ago is already used to support technical decisions concerning planning of maintenance works, the evaluation of budgets according to expected performance levels etc. The first implementation included only three of the indexes surveyed: SFC60 km/h, IRI and percentage of cracked area. After completion of the survey concerning bearing capacity of the pavement over a wide part of the network also this parameter is being included into the PMS. Currently, bearing capacity data are available almost network-wide and the criteria used in the implementation of the bearing capacity in the PMS have been defined. The paper presents the data on the distribution of bearing capacity conditions over the surveyed network and shows how the
influence of bearing capacity has been taken into account in the latest modification of the PMS developed for the main network of Province of Milano. The experience may be of particular interest for other Administrations facing the development of a PMS.