Introduction: Pedestrians account for the majority of casualties and injuries in traffic accidents. As a result, how to protect vulnerable pedestrians is widely being studied. Studies show that slowing the speed of motor vehicles leads to fewer pedestrian casualties(Anderson, et al., 1997). There are three ways of traffic calming from the literature. The physical or psychological traffic-calming device emphasize the physical environmental effect(Ewing, 2001), but overlook pedestrians are part of the environment. Specially designed streets stress on mixed traffic modes(Hamilton-Baillie, 2008), but no detailed research has been done to determine how the applications work. This research proposes to study the significant role that pedestrians play in traffic-calming in mixed-used streets.

Mixed-used streets were investigated with no special design implemented to calm the traffic. Streets in pedestrian-dominated areas where the land-use is not clearly divided, where mixed traffic occurs, were examined. Guigang Main Street in Guangzhou, Guangdong Province, China, was chosen for detailed study. A digital video was set up to tape samples from the street. Video was taken continuously for three days, during which time the number of traffic conflicts were recorded. Movement volumes, pedestrian-motor vehicle interactions, speed, motor vehicle trajectories, special occupancy of the street and yielding behavior were all extracted from the videotape record. Counts, trajectories and timing were all entered in a database using ArcGIS software. In the detailed analysis, I am going to look at 1)the percentage of pedestrians in the street, the fluctuation of the volume and the relation with intersections; 2)the number of pedestrian-motor vehicle interactions, their locations and the causes; 3)how much a motor vehicle slows down when an interaction happen, and from how far it starts to; 4)the relation between motor vehicle’s trajectory and the distribution of pedestrians and its speed; 5)the percentage of motor vehicles yielding to pedestrians in all recorded interactions.

Although trajectories of pedestrians and motor vehicles seemed chaotic, and the number of interactions are large, yet few traffic accidents were observed during the time of field study. X percent pedestrian accounts for the total traffic volume on average, and among the recorded pedestrian-motor vehicle interactions, X percent are motor vehicles yielding to pedestrians. Pedestrians serve as obstacles for motor vehicles. Motorists change their direction and slow down (X%) when they see pedestrian(s) from afar (Xm - Xm), resulting in avoidance trajectories of the motor vehicles. As a result, the speed of motor vehicles is controlled, and road safety is achieved.

Such case proposes a new thinking on traffic calming, making the street pleasant and safe for everyone without changing it a lot. It could be an economical way to calm the traffic in pedestrian-dominant streets. Pedestrians as a traffic calming “device” might be particularly suitable for the regions loaded with large population and server problems of land shortage.