公路隧道洞外适应亮度的确定方法

在分析隧道洞外驾驶员适应亮度内涵的基础上，介绍了隧道洞外亮度￡加的3种确定方法，查表法、环境简图法、黑度法，及等效光幕亮度Lseq的确定方法，并对比分析以L20和Lseq表达隧道洞外亮度的合理性，提出以等效光幕亮度Lseq表达驾驶员驾车接近隧道时的适应亮度更为合理。考虑CIE推荐计算Lseq的各环边界视角为近似值，提出用各环边界视角精确值计算等效光幕亮度Lseq能进一步提高计算精度。

Determination Method of Adaption Luminance Outside Road Tunnel

Based on the introduction of the concept of driver＇ s adaption luminance outside road tunnel, this paper introduced three determination methods of L20 and the determination methods of Lseq After studying the theoretical intension of these two parameters, the thesis argues that the equivalent veiling luminance Lseq can express the access zone luminance more accurately. It is more reasonable to determine the threshold zone lu- minance based on Lseq than on Lseq A polar diagram should be superimposed over the tunnel entrance image in the calculation of Lseq with the angular relationship of the polar diagram conventionally obtained with an ap- proximation calculation method. This paper proposed that that the calculation of Lseq should based on accurate angular relationship of the polar diazram.