Experimental Study on the Impact of Side Wall Coating on Luminous Environment of Highway Tunnel and Visual Characteristics of Human Eyes
(1. Zhongyi New Material Science and Technology Co., Ltd., Chuzhou 239500; 2. School of Mechanical Engineering, Nanjing University of Science & Technology, Nanjing 210094; 3. Anhui Guangyi Scientific Research Testing Co., Ltd., Chuzhou 239000)
Abstract:
The priority in lighting design of highway tunnel is the pavement brightness in the tunnel, while the tun? nel side wall brightness is usually designed to be no more than 60% of the pavement brightness. Side wall is an important part of the luminous environment in tunnel, but its impact on the luminous environment in tunnel and the pavement lighting quality has not drawn much attention. Therefore this paper expounds an experimental study on the luminous environment in a tunnel that is illuminated by LED lights, and on the visual characteristics of human eyes,where the side wall of the tunnel is painted with energy-accumulating luminescent and white or grey coatings. As the study results indicate: With illumination by the same LED light, different types of coatings will bring different brightness levels of side wall. The wall surfaces painted with the energy-accumulating luminescent coating with 0.91 reflectivity and white coating with 0.97 reflectivity have greater brightness than the wall surface painted with the grey coating with 0.37 reflectivity. The brightness ratio between side wall and pavement of a tunnel can be 1.24~1.35. As the side wall brightness increases, the pavement brightness in tunnel and the visual distance of any obstruction on the pavement detected by human eyes will increase. If the pavement brightness remains essentially unchanged while the side wall brightness is changed in a tunnel, the power of the illuminating lamps can be reduced by 14.6% and 9.8% respectively in a tunnel with side wall painted with energy-accumulating luminescent coating and in a tunnel with side wall painted with white coating, as compared with a tunnel with side wall painted with grey coating; besides, the visual distance of any obstruction on the pavement in the tunnel detected by human eyes essentially remains unchanged, the variation pattern of the pupil diameter of the driver in a moving vehicle essentially remains the same, and the driver feels no discomfort. In the lighting design of tunnel, lighting energy conservation of a highway tunnel can be accomplished by painting the side wall with energy-accumulating luminescent coating or a coating with high reflectivity, and so reducing the power of the illuminating lamps.
FENG Shouzhong1 ZHOU Long2 MAO Weixing1 LI Jie3 GAO Wei1
.Experimental Study on the Impact of Side Wall Coating on Luminous Environment of Highway Tunnel and Visual Characteristics of Human Eyes[J] MODERN TUNNELLING TECHNOLOGY, 2024,V61(3): 220-227