A framework for selecting safety treatments for rural roads

Abstract

Road safety is a vital element of the road’s overall function, which is often neglected in decision-making for road maintenance management. As a result, the safety issues, especially in rural roads, remain without funding to implement the necessary countermeasures. One constraint faced by local authorities is the lack of analysis tools to select appropriate safety treatmentswithin the available budget. This study presents a methodology to logically determine the safety treatment criteria for a selected road to increase the safety performance at project level. The decisions regarding the safety treatments are taken based on a linear programming model which optimizes the safety performance of the selected road. Cumulative Safety Index (CSI) represents the safety performance of the road, which is determined based on the prevailing issues on that road. The model comprises the objective function by which maximizes the safety performance of the selected road concerning the number of prevailing safety issue types. This model is used to identify the optimal safety treatment scheme for the road chosen, ensuring prevailing safety issues of the road are effectively addressed. The objective function consists of the Initial CSI of the selected road and the safety improvement after treating relevant issue type coupled with a binary decision variable. This model can also be considered an input to road asset management systems where multi-objective optimization (MOO) models maximize the network pavement condition and maximize overall network safety performance.