Traditionally, a signalized intersection capacity can't be discussed without putting signal timing into consideration. In general signal timing includes determination of cycle length, number of phases, green interval, yellow time and all red. As a result capacity varies with any change of parameters in signal timing. This is the traditional way of estimating capacity, namely timing-based capacity calculation approach. However, at the planning stage if planners or decision makers hope to know the future conditions of the network they have planned it is impossible for them to evaluate the performance in terms of v/c ratio because of undetermined capacity of an intersection. A new concept of so-called "equilibrium-right-of-way based capacity" is introduced in this paper to overcome this difficulty. This capacity is purely based upon the geometries of an intersection (number of lanes and lane allocation) rather than the signalization. The motivation behind introducing this concept intends to have capacity of an intersection be a sole value once the geometries of the intersection are set. Soleness of capacity for interrupted flow facility should be the focus of capacity studies. With this concept, capacity formula based upon the equilibrium-right-of-way is then developed to estimate the capacity of signalized intersections. The result from this study is of great significance for the development of capacity analysis, particularly for the interrupted flow facilities.
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