The quality of smoothness of a newly constructed or overlaid pavement dictates the beginning of pavement management. Adequate acceptance testing procedures and specifications for pavement smoothness have not been available for flexible pavements. Smoothness specifications based on a 10-ft (3.05 m) straightedge has a number of limitations and is difficult to interpret and administer. This paper describes the results of a comprehensive study of several different roughness measuring devices undertaken to select a suitable device in order to develop and implement improved specifications for pavement smoothness. The candidate devices included the 690D Profilometer, Model 8300 Roughness Surveyor, Maysmeter, California Profilograph, and Rainhart Profilograph.
In this study, the 690D Profilometer ranked highest in overall performance. The paper describes the benefits and negative aspects of each type of equipment related to its use for surface-smoothness measurement and acceptance testing of newly constructed pavements and pavement overlays. The results are useful for any agency desiring to improve its smoothness measurement and acceptance testing procedures.