The resilience of an infrastructural network is the network's ability to redistribute traffic when some system members fail. The malfunction could be due, for example, to the collapse of a bridge (total interruption of a network branch) or the opening of a maintenance site (partial cessation of the traffic). In this paper, the resili-ence of Belgium's leading road network will be discussed, supposing that the interruption of some of its branches happens. The modelling, based on the graph theory, involves regional and national roads and high-ways. On the graph, the most important Belgian towns were arranged. Through statistical data on inhabitants and on distance between the towns, a probabilistic modelling of traffic flow was developed. An improvement of the modelling was possible thanks to the data on the real traffic flow directly collected by administrations. Following that, a traffic simulation algorithm with a static path assignment was created in MATLAB envi-ronment. Through the algorithm created it was possible to simulate the movement of each vehicle within the network. This paper presents the assumed modelling hypotheses and the results in terms of resilience (time lost in traffic, increase in kilometres travelled) when some branches of the E42 highway (Tournai - Liège) must be closed to traffic.