Raised Pedestrian Crosswalk (RPC) Influence on Speed Reduction

Raised crosswalks are used in urban areas as traffic calming devices to reduce traffic speed, especially in residential areas or school zones. This paper quantifies the speed reduction effects of raised pedestrian crosswalks (RPCs) based on their geometric characteristics, using before- and on-RPC spot speeds. Geometric characteristics including street width and grade, ramp lengths, top flat crown length and heights, and 4672 spot speed observations on 23 RPCs were surveyed in Qazvin, Iran. These data are essentially repeated measurement data on each individual RPC for which the mixed effects model is well suited. The paper presents the statistical estimation of the parameters of a linear mixed effects model of the dependence of on-RPC speeds on the approach speeds and geometric characteristics of the RPCs. An example of the use of the model is provided.