Alternate method to the use of saturation flow rate for capacity analysis of signalized intersections under mixed traffic conditions

Traffic engineers in many countries have been using saturation flow rate to estimate the capacities of approaches to signalized intersections. The capacities thus estimated are used to evaluate control delay and other performance measures. It has been reported in literature that current methodologies in estimating saturation flows have a standard error of 8% to 10%. Errors in capacity estimates are not completely avoidable but can be minimized to reduce the possibility of making a poor planning or operational decision. Hence in the present research work an attempt was made to verify the applicability of an alternate method of capacity estimation recommended by Feng-Bor Lin and Pin-Yi Tseng for mixed traffic conditions in India. Analysis of the results showed that capacity estimated from the alternate method was in close agreement with that from the traditional method.