As Slovenian freeway infrastructure is aging, maintenance work, managed with appropriate work zones, is already more extensive and will represent even a bigger necessity in the future. Work zones can have a major effect on the traffic flow as they represent a bottleneck; therefore the freeways operate at lower levels of service. Although it is known that work zones affect the freeway level of service, there is a lack of an appropriate model to quantify this effect depending on the work zone type on Slovenian freeway network.
In the master thesis we are taking into consideration several methods for freeway work zone capacity determination that can be found in the literature. We started with collecting data about traffic counters locations with corresponding traffic volumes and various work zones that were present on Slovenian freeway network in prolonged time period. The collected data represent the basis for evaluation of different models for estimating work zone capacity. Demonstrating effectiveness of different existent methods on Slovenian freeway network, comparison among them and analysis of various factors, that affect the capacity, represent the core of the master thesis. We have studied the effect of heavy vehicles, longitudinal grade, lane narrowing and diversion of traffic on the work zone capacity.
For each work zone type we have estimated the capacity and queue discharge rate and compared the values with models and corresponding capacity values, that were developed abroad, and proposed the most suitable model. The usage of the proposed model was also shown on an application example with predicted density values and probabilities of traffic breakdown in a work zone.