Dimensions of most speed-control humps are determined from the engineering judgement of design engineers or past experience of the highway agency concerned. Guidelines for analytical design of hump geometry for speed control are not commonly available. A rational approach is presented in which the geometric dimensions of a hump selected are dependent on the choice of a design 85th-percentile hump-crossing speed and a peak vertical acceleration that governs drivers' choice of hump-crossing speeds. A mathematical half-car model is used to examine the suitability of trial hump designs with respect to the design hump-crossing speed and peak vertical acceleration. To facilitate design analysis, it is proposed that a representative car be selected from the traffic stream as the calibration reference for the half-car model. An example application is presented in which the hump-crossing speeds predicted using the proposed design procedure are found to be in good agreement with hump-crossing traffic speeds measured in Singapore and the United Kingdom.
Abstract