Study on Optimization of Night Illumination in Expressway Long Tunnels

Table 1

Tunnels length and luminosity in middle segment.

Name of tunnel	Yongxing	Lijiahe	Nanwutai	Zhongnanshan	Qingcha
Length/m	1140	3650	2561	18020	1343
Illumination/Lx	60	50	40	30	20