AL-OFI KHALAF AIDHAH2022-05-182022-05-185301https://drepo.sdl.edu.sa/handle/20.500.14154/1970The main purpose of this research is to study the effect of signal coordination on intersection safety and to develop a methodology by which intersection safety could be optimized besides other measures of effectiveness (stops and delays). A signal simulation and optimization model (TRANSYT) was selected and calibrated for the study area so that it simulated the observed number of stops in the field. The cost functions of the optimization model were revised for Saudi Arabian conditions and the costs of rear-end accidents were added as functions of stops and delays.enThesis