Development of Strategies for Improving Traffic Safety and Operations in Winter

冬季驾驶可能非常具有挑战性，因为道路湿滑，降雪和/或吹雪导致能见度降低。由于减少的路面摩擦和有限的能见度，驾驶员通常不愿意使用期望的加速和/或制动功率来对交通事件作出反应。路面标记被积雪完全覆盖也很常见，由于扫雪机作业造成积雪堆积，有效车道宽度或可供行驶车辆使用的车道数量减少。这些特殊的条件表明，道路网络的物理特性和驾驶员行为在冬季的显着变化。清楚地了解这些变化及其对交通流特性和安全的影响对于公路管理机构制定安全、高效和有效的交通管理政策非常重要。

Winter driving can be very challenging due to slippery roads and reduced visibility caused by falling and/or blowing snow. Due to reduced road surface friction and limited visibility, drivers are generally reluctant to use the desired acceleration and/or breaking power to react to traffic events. It is also common that pavement markings are completely covered by packed snow, and the effective lane width or the number of available lanes for moving traffic is reduced due to accumulation of snow caused by snow plow operations. These particular conditions suggest significant variations in physical characteristics of road network and driver behavior in winter. A clear understanding of such variations and their influence on traffic flow characteristics and safety are very important for highway agencies to plan for safe, efficient, and effective traffic management policies.