Citation

Antonios TE, Konstantinos A, Basil P. Transp. Res. Proc. 2023; 69: 13-20.

Copyright

(Copyright © 2023, Elsevier Publications)

DOI

10.1016/j.trpro.2023.02.139

PMID

unavailable

Abstract

The subject of road safety is the main subject of many research programs regarding the road network infrastructure. In the present study, lateral acceleration is recorded through modern instruments, depending on passing speed for each participant driver, for four (4) interchanges and six (6) horizontal curves in total. Essentially, this study emphasizes on how the geometric roads design affects driving behavior. The main purpose is to determine the effect of on-ramp applied speed and curve geometry on lateral acceleration and to create a clear speed profile of drivers during their passage from an interchange ramp. The data collection took place in morning weekend hours, in order to avoid high traffic flows and record the vehicles motions in free flow conditions. As a result, the analysis can examine the main human factors, which affect the driving behavior, too. The selected interchange ramps are mainly trumpets, but also clover and diamond sections and the under-investigation curve radii varies between 28 and 175 meters. For each curve, the presented figures correlate the speed within the curve and the lateral acceleration, while comparisons are made between the lateral acceleration recorded in this research and the literature and guidelines limits. Additionally, V85, V50 and V15 are calculated from the total measurements, taking also into account the data from three additional horizontal curves of Schistos-Skaramagas interchange investigated one year earlier. Therefore, aggregate speed profiles are created and presented. In conclusion, the results show that an increase in the speed leads to an increase in the lateral acceleration as well. Also the limit values of lateral acceleration received by drivers into smaller-radii curves, significantly exceed the maximum driver comfort limit and the maximum driver safety limit, as well as the provided -by design guidelines- values, in contrast to larger-radii curves. Regarding the speed within the curve in respect to the horizontal radius, it was found that as the radius of the curve increases the applied speed also increases. However, this increase is more abrupt for the smaller radius curves compared to the larger ones. Moreover, de Jong's models include higher values than the measurements made in the present study and much more than those presented by Jafarov's and Zaluga's model (2020), especially in cases of large horizontal radii.

Language: en

Keywords

geometric roads design; interchanges; lateral acceleration; Road safety; speed profiles