Road Capacity at Bus Stops with Mixed Traffic Flow in China

In many Chinese cities, traffic streams near bus stops differ from those of bus stops in developed countries. There are usually two lanes at a Chinese curbside stop: a nonmotorized lane and a motorized lane. Bus stops are often located on the nonmotorized lane. When a bus dwells at a curbside stop, nonmotorized vehicles, mainly bicycles, will move to the motorized lane. Thus, the presence of a stopped bus creates a temporary conflict between bicycles and cars, reducing road capacity. A road capacity model based on gap acceptance theory and queuing theory is presented for mixed traffic flow at the curbside stop. Traffic conditions are classified into two types: no stopped bus and presence of stopped bus at the curbside stop. The probabilities of no bus and presence of bus at a stop can be obtained by using the queuing model of bus streams. Under the former condition, the bicycle stream and the car stream have no conflict, and car capacity is not affected by the bicycle stream. Under the latter condition, the conflict between bicycles and cars on the motorized lane leads to an effect on car capacity by the bicycle stream. The effect on car capacity can be derived through gap acceptance theory. Car capacity at the curbside stop is a function of three types of traffic stream-buses, cars, and bicycles-and it may be applicable in traffic analysis and the design of bus stops in other developing Asian cities.