Optimal analysis of optical parameters of road tunnel opening scrimshaw

Abstract

With the development of technology, more and more cities and highways are installing light reducing structures at the tunnel openings to improve traffic safety and reduce the “black hole effect” and low-angle sunlight glare effect. However, the existing scrims have poor road surface uniformity, bright and dark streaks and uneven road surface brightness, which can bring negative impact on driving. In order to balance the safety and comfort of tunnel light sheds, a new technique is proposed to reduce the negative effects of light sheds based on the multi-source effect of light diffusion panels. The results show that by arranging light diffusion panels on the top of the scrim, the daylight is fully diffused and then irradiated to the road surface under the scrim, avoiding the undesirable phenomenon caused by direct sunlight on the road surface. After the indoor test and numerical model analysis, the effectiveness of the technology is proved to be in compliance with the design specification, and the undesirable phenomena such as bright and dark streaks are avoided, thus ensuring the safety and comfort of traffic at the tunnel entrance. In addition, the average brightness of the road surface of the top arrangement of light diffusion panels is better than that of the two sides, and the light intensity distribution curve of No. 2 panel among the four light diffusion panels used in this paper is the best. The technology can also control the brightness level of the road surface under the shed through the area of light diffusion panels, thus reducing the carbon emission of the tunnel lighting system and achieving the unity of safety, comfort and low carbon environment protection.