Study of road tunnel threshold zone lighting reduction coefficient

公路隧道入口段亮度折减系数研究（英文）

The luminance in the road tunnel threshold zone attracts broad attention due to its enormous energy consumption and direct influence on tunnel transportation security.Current lighting design methods in threshold zones mostly adopt the reduction coefficient method.However,the determination of reduction coefficient k simply considers tunnel design speed and flow rate,while excluding outside tunnel luminance and threshold zone color temperature and luminance,which have a major impact on driver visual adaptation.Existing problems in the determination of k value are analyzed;a visual performance experiment is utilized;and the reaction time of drivers in changeable outside tunnel luminance and threshold zone color temperature and luminance conditions is obtained;thus,the equations concerning reduction coefficient variation law are derived.In the end,a comparative analysis is made of the k values of the reduction coefficient stipulated by various norms under different color temperature conditions.

公路隧道入口段照明因能耗巨大且直接影响隧道交通安全而备受关注。现行入口段亮度设计方法多利用折减系数法,在确定折减系数k时仅考虑了隧道设计车速和车流量,对驾驶员视觉适应有较大影响的隧道洞外亮度及入口段的色温和亮度未被考虑。文章分析了现行k值确定过程中存在的问题,利用视觉功效实验获得了驾驶员在隧道洞外亮度不断变化且隧道入口段色温和亮度不同条件下的反应时间,进而得到折减系数变化规律的关系式,最后将不同色温下的折减系数与各规范规定的k值进行了对比分析。