Citation

Davis TD. Transp. Res. Rec. 1981; 811: 15-19.

Copyright

(Copyright © 1981, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

unavailable

PMID

unavailable

Abstract

A study conducted to find the need for improving delineation in construction zones with long-term lane closures or diversions is described. The need for improved delineation was established through two means: (a) a committee of traffic, construction, design, research, and specifications engineers and (b) positive guidance, a technique that develops improvements to the highway information system from the driver's viewpoint. Once the need was established, improved delineation concepts were developed and tested in actual construction zones and evaluated for effects on traffic performance and driver visibility. The experiments showed that (a) although 12.70 x 25.40-cm (5 x 10-in) yellow high-intensity reflectors were less expensive, more easily checked, and more reliable than steady-burn lights, reflectors did not change vehicle speed averages and variances or the proportions of vehicles using the lane adjacent to the reflectors; (b) although tall vertical panels used up less space and could be seen over the tops of lead vehicles when compared with type 3 barricades, panels decreased lane encroachments and did not change vehicle mean speeds or variances; (c) raised pavement markers as a paint supplement reduced undesirable lane weaves and encroachments, day and night; (d) removable traffic tape was easy to install and easy to remove and caused no problems while in use; and (a) raised pavement markers as a paint replacement were easy to install and easy to remove, and they reduced lane weaves day and night and reduced nighttime lane encroachments.