Most state highway agencies employ pavement-smoothness specifications for newly constructed surfaces on rigid, flexible, and composite pavements to provide ride quality for the traveling public and to promote overall construction quality. Many specifications incorporate provisions for incentive/disincentive payments on the basis of initial paving smoothness and these incentives and disincentives can be sizable. Given that pavement-smoothness specifications are used widely, research was needed to examine the usefulness of these specifications, to assess the specifications and measurement methods currently used, and to develop recommendations for guide specifications and measurement methods.

The objectives of this research on flexible, rigid, and composite pavements were to (1) determine the impact of initial smoothness on (a) total quality of the pavement as constructed, (b) ride quality of the pavement over its life, and (c) the pavement service life; (2) determine the effects of existing smoothness specifications on the initial as-constructed smoothness; (3) determine cost-effectiveness of smoothness specifications, including incentives and disincentives; and (4) recommend methods to specify and measure initial smoothness on construction projects.

Research is complete, and the contractor's final report is available on the Internet as NCHRP Web Document 1 where it can be browsed or copies can be ordered. The contractor's final report has also been distributed to the state departments of transportation.