Analysis of the state of the road infrastructure at the intersection of the Dombirobod Small Ring Road and Chilonzor street in Tashkent

Abstract

The article analyses the state of the road infrastructure and of the traffic flows at the intersection of the Dombirobod Small Ring Road and Chilonzor street, one of the busiest transport nodes of Tashkent. A field inventory of the traffic control devices and a field count of the traffic flow on all four approaches were carried out, separately for the entering and the leaving vehicles, over the morning period 06:30–09:30 in 30-minute intervals and over the evening peak hour. The inventory showed that the intersection is provided with a traffic signal to 70 % and with direction-of-travel signs to 50 % of the required extent, while the priority sign, the pedestrian crossing sign and the speed-limit sign are completely absent. During the morning peak hour 08:00–09:00 the intersection is entered by 5121 veh/h and during the evening hour 17:00–18:00 by 6000 veh/h, so that the design peak occurs in the evening and exceeds the morning one by 17.2 %; the approaches of the Small Ring Road account for 65.0 % and 57.0 % of these volumes respectively. On this basis a two-phase signal control scheme was calculated by the Webster formula: with a saturation flow of 5400 veh/h per three-lane approach and a lost time of 18 s the cycle length is 85 s, rounded up to 88 s, with effective green times of 44 s and 26 s, which gives a degree of saturation of 0.78 on both critical approaches. The installation of the missing traffic signs and the renewal of the road markings are proposed in addition.