PADMA-EXPERT SYSTEM FOR FLEXIBLE PAVEMENT DETERIORATION AND MAINTENANCE

This paper illustrates the power of expert systems for helping engineers to develop decision support systems for road maintenance, by describing the PADMA (PAvement Deterioration and MAintenance) system. PADMA can function as an expert system in deciding the cause of distress in flexible pavements, and in selecting the most appropriate maintenance treatment to be carried out. It can make experience and expertise in pavement maintenance management available to field engineers. It can develop an expert system to decide the appropriate type and thickness of flexible overlays over weak flexible pavements. It can use field data to calibrate the expert system model. Several other actual or prototype expert systems, developed in North America for transport engineering, are described, including: ROSE, SCEPTRE, Concrete Pavement Evaluation, PRESERVER, and OVERDRIVE. DEKBASE was developed as a knowledge-based expert system at the Indian Institute of Technology, Madras, India. It was found to be a useful development environment for PADMA, because of the flexibility allowed in its control structure. PADMA's main purpose was to test the feasibility of applying expert systems to pavement maintenance. Its features are described in some detail, including the pavement deterioration models that it uses.