Operational Evaluation of Road 2 – Road 6 Intersection at Obafemi Awolowo University, Ile – Ife, Osun State, Nigeria.

Abstract

Over the recent years traffic at the Road 2 – Road 5 intersection has been observed to be high at peak hours. This situation sometimes becomes frustrating as a result of long queues. Accidents have even occurred in some instances. The need to proffer solution to this problem, therefore becomes imperative, hence this study. The geometric characteristics and the traffic and the signalized conditions of the intersection were determined using standard procedures  The intersection geometrics show that, there are two lanes on all approaches, with an average width of 3.65 m. The terrain is level and there is no storage bay. Raised islands are provided to separate the traffic streams. There are no lane and pedestrian markings. The saturation flows (s), for the East Bound (EB), West Bound (WB), North Bound (NB) and South Bound (SB) traffic, were, 2306, 1948, 1561 and 1569 veh. / h respectively, while the critical v/c ratio value for the intersection was, 0.54.The uniform delay, d₁,for EB and  WB, and  NB and SB, were 10 and 26 sec. / veh.  respectively; while the values for their incremental delays, d₂, were, 0.44, 0.56, 0.41 and 0.47sec. / veh. respectively. The average intersection delay is, 13 sec / veh., which put the level of service (LOS), at B. It can therefore be concluded that, there is a slight delay at the intersection, which could probably be attributed to the inadequate geometrics of the intersection. A new geometric configuration was therefore proposed to eliminate this delay.

Keywords: Intersection, Geometrics, Saturation Flow, Critical v/c Ratio, Average delay and Level of Service (LOS).