Abstract. Speed reduction markings (SRMs), which are widely used on highways and urban roads in China, are designed to inform drivers of the upcoming road conditions and thus encourage them to reduce travel speed. The objective of this paper is to test the effectiveness of SRMs on drivers’ operating performance and decision to decelerate in downhill segments on urban roads. Data of gas and brake pedal use was collected in a driving simulator experiment, and a subjective questionnaire survey was conducted. Two indicators—the operating frequency and operating power—were proposed to evaluate drivers’ operating performance due to SRMs. Results of the subjective questionnaire study showed that the majority of subjects were affected by SRMs while driving through downhill segments with distinct roadway grades (3%, 2%, 1.5% and 1% in experimental scenarios). In terms of the operating frequency, the results of the analysis of variance with repeated measures (rANOVA) and the contrast analysis (S-N-K method) showed that transverse speed reduction markings (TSRMs) were significantly effective in influencing drivers’ frequency of letting off the gas pedal when roadway grades of downhill segments were 3%, 2%, and 1.5% (p<0.05), while longitudinal speed reduction markings (LSRMs) had little effects; both types of SRMs are effective in increasing the frequency of pressing the brake pedal in all four downhill segments. For the operating power, the gas pedal power was significantly affected by TSRMs in all four roadway scenarios; TSRMs also tended to increase the brake pedal power when the roadway grades were 2% and 1.5%, while both types of SRMs had similar effects in road sections with roadway grades of 3%.
Experimental Research on the Effectiveness of Speed Reduction Markings based on Drivers’ Operating Performance: A Driving Simulation Study
