The purpose of the road lighting standard is to provide a basis for the engineering and technical personnel engaged in road lighting design to make reasonable road lighting design, in order to create a lighting condition for the driver and pedestrian to meet the visual operation requirements, thereby reducing traffic accidents and improving night traffic. Transportation rate. With the standard, designers can avoid the need for high lighting quantity and quality, thus avoiding the waste of electric energy and achieving energy saving. This chapter first introduces China's relevant road lighting standards; secondly, it introduces the road lighting standards recommended by the International Commission on Illumination (CIE), as well as the current standards and standards of some countries such as Japan, the United States, the Soviet Union, the Federal Republic of Germany, the United Kingdom, etc. The standard is simple to analyze and compare. There are many contents related to urban road lighting design standards in China, and this section will focus on the introduction of road lighting standards. Road lighting standards (1) Urban road lighting is divided into 5 levels according to express roads, trunk roads, secondary trunk roads, branch roads and residential roads. (2) The illumination of motor vehicle lanes should meet the four indicators of average brightness (or illuminance), brightness (or illuminance) uniformity, glare limitation and inducement. Roads mainly used for non-motor vehicles and pedestrians should meet the average illuminance evaluation indicators. (3) The lighting standards of roads at all levels shall comply with the provisions of Table 5-1. (4) The average illuminance value of the non-motor vehicle lanes of the three roads and the four roads is preferably 1/2 of the corresponding motor vehicle lane. (5) The average illuminance of roads and sidewalks mainly for non-motor vehicles and pedestrians should be no less than 1 lx. (6) Newly installed light sources and lamps should consider the maintenance factor of the lamps and require the initial surface of the road. The brightness (or illuminance) value is increased by 30% - 50%. (7) The average level of illumination of pedestrians is 15 lx at night and 50-100 lx during the day. (8) When selecting the lighting standards for motor vehicles, the nature and scale of the city should be considered. Generally, small and medium-sized cities can adopt the corresponding lower level 1 standard depending on their road type. Some explanations of road lighting standards (1) From the perspective of road lighting, Yingbin Road, the main road leading to government government buildings and large public buildings (such as sports halls, exhibition halls, large theaters, etc.), downtown or The roads in the center of the business district can still be used to illuminate the main road. (2) Table 5-1 shows the brightness and illuminance values. The set of standards is based on the fact that it is scientific and reasonable to consider the brightness based on the basis of illumination. The driver directly feels the road surface brightness. Not illuminance. At the same time, the standards of most countries are based on brightness. On the Other hand, considering the current situation in China, it is still difficult to fully implement the brightness standard at a time. Therefore, it is proposed that there are no strict correspondences between the two sets of standards. For example, when the brightness uniformity is 0. 4, the illumination uniformity is Not necessarily 0. 4. Where there is a condition for brightness calculation and measurement, the brightness standard shall prevail. (3) The lighting standard of the road in the residential area (ie Lane) only specifies the illuminance value because the users of this road are mainly pedestrians, and their visual operation characteristics are different from those of motor vehicles, and they cannot provide uniform observation. The position and the reflective characteristics of the road surface are also very different, so it is meaningless to use the brightness index at this time. (4) The brightness (or illuminance) uniformity specified in Table 5-1 is the total uniformity, that is, the ratio of the minimum brightness (or illuminance) to the average brightness (or illuminance) value in the road surface measurement area where the dots are uniformly distributed. At present, CIE and some countries' standards and specifications give two kinds of brightness uniformity indexes, namely total uniformity and longitudinal uniformity. However, considering that the total uniformity is more important than the longitudinal uniformity, combined with the current actual situation in China, only one indicator of total uniformity is given. Moreover, there are still many countries (such as the Soviet Union |, the United States) standards that only specify an indicator of total uniformity. (5) The glare restriction criteria specified in Table 5-1 are given in accordance with the CIE 1965 standard. At present, CIE and some countries' glare control standards give specific values ​​of glare control level (G) and threshold increment (TI), and some still use the CIE 1965 standard. Considering the specific situation in China, it is still difficult to limit the glare according to the specific values ​​of G and TI. It is generally considered that the lamps of the cut-off type and the half-cut type are mostly satisfied by the specific indicators of G and TI. For example, Schrader (1966) of the Netherlands has studied and calculated the corresponding G value according to the CIE 1965 regulations on truncated and half-cut lamps. The result is: for the cut-off type lamp, G=6.7: For half-cut light fixtures, G = 4.8. These two G values ​​can meet the recommended value of CIE (4-6). (6) The non-cutting luminaires caught in Table 5-1 are examples of enamel umbrella covers (lamps) that are still widely used in many urban areas without modification. For example, the enamel umbrella cover used by the Beijing Street Lamp Management Office shows that when the 250W and 400W high pressure sodium lamps are used, the light intensity value in the direction of the vertical angle of 80 ┾ is 116-119 cd/1000 lm.90 ┾. It is 107-109cd/1000 lm, which greatly exceeds the specified values ​​of the cut-off and half-cut lamps defined by CIE. Therefore, the use of such enamel umbrella covers should be prohibited for expressways and primary and secondary trunk roads. (7) The brightness level of the road surface has a great relationship with the road material. The average brightness of the square of 1 cd/m is also obtained, and the average illuminance required for the road surface of different materials is different. At the same time, the brightness level is also related to the degree of wear of the road surface and the type of light distribution of the lamp. In the past few years, the CIE specified four types of standard road surfaces. The US standard accepted the illumination corresponding to the four types of road surfaces when the CIE recommended to achieve the specified brightness value. Considering that asphalt pavement and concrete pavement are generally used in urban main and secondary trunk roads in China, Table 5-1 only specifies the applicable illuminance value of asphalt pavement. The illuminance required for concrete pavement can be about 30% lower than that of asphalt pavement. (8) In view of the fact that many cities in China have built a number of three roads and four parking spaces separating motor vehicle lanes and non-motor vehicle lanes, it is necessary to stipulate the lighting standards for non-motor vehicle lanes, that is, slow lanes. According to the requirements of environmental lighting in the CIE proposal and with reference to the norms and standards of some countries, the roads separated by the sub-carriage lanes of motor vehicles and non-motor vehicle lanes are specified. The illuminance value of non-motor vehicle lanes should be 1/2 of the motor vehicle lanes. . (9) Road lighting is set according to the speed of the vehicle on the road, the traffic volume, the pedestrian flow and the environment in which the road is located, and is not necessarily related to the scale nature of the city. However, due to the current lack of detailed statistics on traffic flow, traffic accidents, etc., and generally speaking, small urban roads can reduce the requirements of the first level standard accordingly. Since road lighting and reflecting the city's appearance are closely related to the tourism industry of the exhibition, some streets in key tourist cities can not lower the standard. The values ​​in Table 5-1 apply only to dry roads because the reflective properties of the road surface are very different in wet and dry conditions. The lighting indicators in the dry state do not reach the wet state. Therefore, another set of indicators should be specified for wet roads. However, research work at home and abroad is not yet mature enough to develop standards suitable for wet roads. Therefore, China does not consider lighting problems on wet roads.
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