Three issues are considered equally important in roadworks: safety of road users, no delays to traffic flow, safety of road workers. Collisions with lane closure trailers - about 50 annually - are a serious problem. Between 1983 and 1990, traffic delays due to roadworks decreased from 30% to 10%, due mainly to night working, use of specialised road equipment etc. Since 1990 there has been an increase in congestion, there are queues even at night. The ongoing increase in traffic density has nullified efforts to reduce delays. The safety of road workers has become an important political issue. There are many shortcomings in separating road workers and traffic. A large scale action programme has started. Work has been speeded up on revised guidelines for roadworks, and they will be issued in August 1995. Important new points are: (1) large scale use of temporary concrete and steel barriers; (2) greater speed limit differentiation at work zones; (3) new colours (black and yellow) for traffic signs preceding work zone; (4) greater use of contraflow systems and diversions; and (5) better coordination and communication between local authorities in planning roadworks. More research does not always improve predictive performance. (A). This paper was also published in Accident Analysis & Prevention, 1996, Vol. 29, No. 3, p. 339-347 (IRRD 882481).
Samenvatting