A methodology is presented for determining a pavement distress index (PDI) needed for pavement management purposes. It involves a Delphi-like process for the acquisition of expert opinion through a series of questionnaires and the derivation of weighted average condition measures. Emphasis is placed on making the methodology useful for a wide range of pavement preservation decision-making purposes. The index formulation is based on two types of information, namely, (a) individual distress ratings along nominal lengths of pavement, and(b) a set of weighting values associated with the various distress types and severity-extent combinations. The PDI is used as a condition measure in various other analytical methodologies within the pavement management system of the New York State Thruway Authority. Important aspects of the methodology are discussed and the index calculation technique is demonstrated in an illustrative example. It is concluded that the developed index is a viable single measure of pavement surface condition useful for pavement management purposes. (A)
Abstract