Capacity Evaluation of ISKON Intersection on S.G Highway in Ahmedabad-A Case Study

Alpana Jha

Abstract: Space sharing intersection e. g rotaries and pretimed signals are widely used to control the intersections. Space sharing intersection are intended to give equal priority and permit continuous movement of all intersecting vehicle flows. For higher traffic volumes, space sharing intersections such as rotary is not preferable due to increase in congestion and overall intersection delay and conflicts. In pretimed signal, green times for the phases remain constant for the particular period of the day, although demand fluctuates during that period. This problem can be eliminated by providing over bridge at rotary intersection. This study presents literature review on Rotary Intersection and capacity and level of serviceon and literature on case study. ISKON Cross Road on S. G Highway in Ahmedabad was selected as a case study intersection. The flow rate, saturation flow rate and its adjustment factors, capacity, volume to capacity ratio, delay for lane group, approaches and intersection as whole and delay comparison with level of service were calculated as described in highway Capacity Manual 2000. Study proves that ISKON Cross Road at-grade intersection was required to be converted to grade separated intersection to reduce congestion and delay.

Keywords: Rotary intersection, Capacity, Level of service, delay, Critical v/c ratio