This research study of pavement smoothness measurement was conducted in order to develop and implement an improved highway smoothness construction specification on asphalt concrete pavements. Achieving a higher level of smoothness on highways during construction results in savings to the taxpayer due to reduced wear and tear on vehicles, and longer highway life. Although the current ADOT specification used for highway smoothness addresses localized smoothness problems, it is difficult to administer due to the measurement system used, and provides little impetus to the contractor to improve his quality of work with respect to overall highway smoothness. This study provided data to assist ADOT in developing a new smoothness specification that would provide incentive to contractors to construct smoother pavements and which is easier for ADOT to administer. In order to provide incentive to contractors, a pavement smoothness construction quality control draft specification and associated measurement procedure was produced.

The study objective was to identify a lighting system which has a lower power cost and reduced maintenance requirements and which provides adequately for motorists' needs in terms of legibility and illumination level. Twenty-five candidate lighting systems were identified through a review of technical data and specifications for lamps and fixtures by an independent lighting expert. Photometric tests and computer analyses of sign illumination levels reduced the number of candidates to ten alternative systems which were then field tested. Each alternative lighting system was tested for 10 to 14 months. Sign luminance was measured with a telephotometer. Power consumption was monitored. Maintenance requirements and lamp life were noted. A human factors study determined legibility distance and rated viewing comfort, lighting uniformity, and color rendition. An economic analysis was performed which considered the initial cost of acquiring and installing the lighting systems and annual costs for electric power, washing, relamping, and ballast replacement. A lighting system using the high pressure sodium light source was recommended. Compared to the existing commonly used fluorescent system, it uses one-third as much electric power and has about one-third of the annual owning and operating cost. The recommended system has a satisfactory illumination level and provides the best legibility distance of the ten systems tested.