Excessive and inadequate speeds represent one of the most important causes of traffic accidents, and significantly determine the resulting consequences.
The research in this paper refers to the analysis of speeds in one of the important corridors of the main city streets in the city of Rijeka, Croatia. Both streets are approx. 1.5 km long, mostly one-way and two-lane, located in a mixed mostly residential area where important recreational and tourist facilities are located also. Both streets have experienced significant changes in the recent years - the construction of an additional road network in a wider area caused a reduction in the importance of the streets in ensuring transit traffic and in traffic loads. The main intersection of the mentioned streets with the third access road was reconstructed - from a non-signalized intersection to a roundabout, certain traffic calming measures were introduced, and the reduction in traffic volume caused the appearance of long stretches of illegal street parking.
Traffic counting and speed measurements were carried out at several cross-sections on this corridor in 2016 and 2019, when the construction of the roundabout had not yet begun. The aim of this research is to determine how much the construction of the roundabout and other described planned measures and unplanned changes in both streets affected the flow of traffic - primarily speed and traffic volumes. Traffic counts and speed measurements were repeated in 2023 at the same locations and in the same way as done before. A comparison of the results of operational (V85) speeds shows that traffic in the zone did not calm down due to the effect of the traffic and construction measures taken.

speed measurements; planned measures; traffic elements; road elements