This article examines the indicators of the highways operational condition and their dependence on the vehicles traffic intensity, the traffic type, the vehicles speed and the degree of the road loading, as well as the impact of these indicators on road safety. The purpose of this article was to determine the dependence of the roads operating ability on the impact of the transport, which is moving along them.It's determined that there is direct dependency between car weight parameters variation and increasing strength and efficiency requirements for road surfaces. The research revealed that most car accidents occurs under the influence of particular adverse factors and their combinations. As a result of the analysis, the relationship between the weight parameters changes of cars and the working capacity of road surface dressing has been established.