Mavromatis S., Stamatiadis N., Psarianos B., Yannis G, “Controlling Sag Vertical Curvature Rates Based on Variable Grade Stopping Sight Distance Calculation”, Advances in Transportation Studies, Issue 38, 2016, pp. 33-44.

Stopping Sight Distance (SSD) is a key control element which directly affects the suggested values of crucial road design parameters. Although there is a significant difference in SSD values between upgrades and downgrades, many Design Policies ignore the grade effect during vehicle braking on variable grades. Such a case is experienced during the determination of sag vertical curvature rates where the relevant SSD values