Bottle-necks on freeways: Traffic operational aspects of roadworks

In the Netherlands roadworks are one of the causes of congestion on freeways. Due to the growth of the mobility and because of this the freeway volume, the expectation is that congestion will occur more often in the future. Compared to the capacity found at lanes of homogeneous freeway sections the capacity of lanes at freeway work zones is much lower. The aim of the research is to find an explanation for the capacity reduction caused by roadworks. Therefore the behaviour of the traffic flow at short term maintenance sites has been analysed in the influenced area of a two-lane roadway of a freeway of which one lane is closed. Detector-measurements have been carried out on two sites.