Investigation of the Impact of Severe Winter Weather on Volume of Passenger Cars and Trucks on Primary Highways

摘要

Based on large traffic and weather data sets from weigh-in-motion sites, permanent trafficcounters and weather stations in Alberta, Canada, an investigation is carried out to study impactsof winter weather on volume of passenger car and truck traffic. Multiple regression models aredeveloped to relate truck and passenger car traffic variations to winter weather conditions.Statistical validity of study results are confirmed by using statistical tests of significance.Considerable reductions in passenger car and truck volumes can be expected withdecrease in cold temperatures. Such reductions are higher for passenger cars as compared totrucks. Due to cold and snow interactions, the reduction in car and truck traffic volume due tocold temperature could intensify with a rise in the amount of snowfall. For passenger cars,weekends experience higher traffic reductions as compared to weekdays. However, the impact ofweather on truck traffic is generally similar for weekdays and weekends. Interestingly, anincrease in truck traffic during severe weather conditions is noticed at one of the study sites.Such phenomenon is found statistically significant. None of the past studies in the literature havepresented the possibility of traffic volume increases on highways during adverse weatherconditions; which could happen due to shift of traffic from parallel roads with inadequate wintermaintenance programs.It is believed that the findings of this study can benefit highway agencies in developingsuch programs and policies as efficient monitoring of passenger car and truck traffic, and planfor efficient winter roadway maintenance programs.