When airport pavements are damaged by traffic and environmental effects so that their serviceability or load carrying capacity is degrated, we need to consider
maintenance or rehabilitation works for them. We have conducted many researches in order to establish a new maintenance and rehabilitation system for airport pave
ments.
　For this, Pavement Rehabilitation Index (PRI) equations have been developed to objectively evauate pavement surface condition.
　Non-destructive methods for evaluating the load carrying capacity of airport pavements have been developed to take the place of the conventional destructive evaluation methods. Dynaflect deflections are used for asphalt pavements and Falling weight Deflectometer (FWD) deflections for concrete pavements.
　Some new overlay thickness design methods have been proposed. One is a thickness design method for an asphalt overlay on an existing asphalt pavement using Dynaflect deflections and another is a thickness design method for an asphalt overlay on an existing concrete pavements using three-layer elastic theory. New bonding techniques have also been developed for bonded concrete overlays and a prestressed concrete precast slab pavement has been developed to replace normal concrete pavements in which concrete slabs are palced in-situ.
　Finally, a new maintenance and rehabilitation system has been proposed.