1 on-site investigation and analysis of results
1. 1 Research object and content selection
According to the recommendations in the CIE Technical Report 136-2000 Publications Urban Lighting Guide, this paper divides the roads in residential areas into two types: collecting roads and local roads, and investigating them separately. The collecting road here refers to the main road of a residential area, which connects all local roads with one main line.
Because the road users in the residential area include motorists, bicycles and walkers, which are mainly pedestrians, especially for local roads, their visual operation characteristics are different from those of motor vehicles, and they cannot provide uniform observation. Position, the reflective characteristics of the road surface are also very different, then the significance of the use of brightness indicators is not very obvious.
Therefore, in the survey, when selecting specific photometric indicators, the horizontal illumination, vertical illumination and semi-cylindrical illumination, and illumination uniformity are the main measurement items. Statistics on the selection and installation of light sources and luminaires are also provided (see 1).
1Chongqing residential area road lighting research
1. 2 analysis of research results
In our research, we found that it is often difficult to separate the branch roads on the street from the current collection roads, so only the representative community roads were measured when the residential area was selected.
It can be seen from the survey results that the road lighting level of the residential area under investigation is basically meeting the requirements of the Urban Road Lighting Design Standard CJJ45-91 (hereinafter referred to as the “Old Standardâ€), but if it is evaluated according to the “New Standardâ€, None of them can reach the standard level of lighting, especially for the collecting roads, which is obviously low, and only the lights are used to supplement the lighting. There are three main reasons for analyzing the reasons: First, because our research objects are all located in the main city, the security measures are better, belonging to the safe area, and the lighting level can reduce the requirements; second, related to the developer, low illumination On the one hand, it can create a quiet leisure atmosphere, on the other hand, it can save money; the third is the problem of light source and lamp selection, such as the Huilong Bay community, using thin-tube fluorescent lamps and upper-lighting and reflection screens on the collecting road. The lighting measures result in a lower illumination of the road surface.
The light source of each residential area is mostly a small-diameter fluorescent lamp or a compact fluorescent lamp; in the way of lighting, the collecting roads are mostly double-sided cloth lamps, and the local roads are mostly single-sided cloth lamps; although most of the lamps are non-cutting type, However, the interference with neighboring houses is basically considered, and the upper part is generally provided with a screen.
2 Functional requirements analysis of road lighting in residential areas
Nowadays, people's nightlife has not been reduced by the fall of night. Outdoor lighting is required to have the functions of safety, orientation and comfort. As the most closely related residential area road lighting with residents' personal and property, it has its own functions and use characteristics.
2. 1 security
The first is the safety of residents' personal and property. Although outdoor lighting is mainly traffic-oriented, with the frequent travel of people at night, the crime control rate has become one of the main functions of outdoor lighting, especially in pedestrians. The characteristics of the user's residential road are more obvious. And historically, the main reason for the introduction of street lighting, especially in large towns, is to reduce crime rates. In the past 20 years, crimes involving people and property, especially those parked, have been growing steadily.
Secondly, traffic safety, a large number of accidents involving pedestrians, and evening accidents occur in residential areas, which are in the vicinity of schools and entertainment centers, as well as in purely residential streets. Children play on the sidewalks or on the streets, and the roads outside the designated crosswalks of the old and the weak and others cross the road. In addition, the danger of animals and pets on the street is considered. They cause motorists or motorcyclists. Or cyclists (assisted or pedaled) directly hurt, or suddenly turn to accidents that occur when they bypass them. In any case, the relatively high incidence of accidents on these streets cannot be ignored.
Safety is affected by several aspects: identification (human, other obstacles), glare (TI), visual orientation, and environmental factors (SR).
Among them, the identification is the most important for the roads in residential areas, and it is also our most concerned issue. The so-called identification means that suitable road lighting provides sufficient visual information for road users (pedestrians, drivers) to identify and find objects within a limited distance. More modern semi-cylindrical illumination is increasingly recommended as an indicator for evaluating identification. The semi-cylindrical illumination is mainly the most important lighting requirement in the nighttime of the pedestrian use area. It is able to identify other people who are approaching or leaving a certain distance nearby. In order to provide the necessary sense of security (see 1).
2. 2 guiding and comfort
The streetlight guidance performance of the residential area helps people identify the road ahead, especially for people unfamiliar with the area. And it is convenient for drivers and pedestrians to respond to the road information ahead.
The lighting method of road lighting can convey this information. Comfort is here mainly reflected in glare, light pollution and uniformity of illumination. In addition to the glare caused by the illuminating of the illuminator on the collecting road, the lighting is suitable for illuminating the sidewalk behind the pole, there is an unavoidable problem, that is, unpopular light. Entering the windows of residents along the street, this is especially serious for pilhouses and other houses without front gardens. There is also good uniformity of road lighting, which is not only important for improving the visibility of the target, but also for the residential area, the visual comfort of pedestrians and drivers, and the creation of a pleasant residential lighting environment.
3 improvement measures for road lighting design in residential areas
3. 1 road lighting level in residential areas
The actual residential roads include not only the residential roads and sidewalks for non-motorized vehicles and pedestrians, but also the collecting roads for drivers, bicycles and pedestrians. These collecting roads should basically belong to CIE 115― For the M2 and M3 roads in the 1995 publication, the lighting requirements for the branch roads in the New Standard can be referred to for their lighting requirements.
2 Recommended values ​​for PHILIPS road lighting
3 CIE standard recommended value
4 CIE lighting requirements for urban traffic
Note: The average illuminance listed in 12~4 is only applicable to asphalt pavement. If it is cement concrete pavement, the average illuminance value can be reduced by 20%~30%.
The uniformity listed in 23 was originally the average illuminance Î minimum illuminance (Eav Î Emin).
In 34, P3 represents a moderately suitable road for pedestrians or pedal cyclists, and P4 represents a road that is less used by pedestrians or pedal cyclists in the evening. Only the adjacent property is contacted. The road used by P5 is the same as P4, but Can only be used where you can ignore the danger of crime.
The above-mentioned recommended average illuminance values ​​of the horizontal plane (see ~) are higher than the "old standard", but they are all lower than the current "new standard" in China. It can be seen that the lighting level in recent years is an increasing process, the standard value of lighting The improvement is in line with the current situation. For the comparison of the lighting standard values ​​of the old and new standards, see 5 and 6.
5 residential area motorway road lighting standard value
6 residential area pedestrian road lighting standard value
Note: The average illuminance listed in the table 1 is only applicable to asphalt pavement. If it is cement concrete pavement, the average illuminance value can be reduced by 20% to 30%.
2 When designing, the standard requirements can be adjusted according to the actual local security situation.
3. 2 light source and lamp selection
The "New Standard" recommends high-pressure sodium lamps or low-power metal halides for mixed roads between motor vehicles and pedestrians in residential areas; low-power metal halides, thin-tube fluorescent lamps or compact fluorescent lamps can be used for pedestrian roads in residential areas.
Comparison of 7 street lighting sources in residential areas
In addition, in the selection of lamps, it is necessary to consider the problem of light pollution of street lamps to residents along the street. In actual engineering, the choice of lighting fixtures, including light poles, is largely due to the need for daytime and evening aesthetics, as well as coordination with the surrounding environment. For local roads, when decorative lamps are used, the luminous flux ratio should not exceed 25%, and the mechanical strength should meet the requirements of the corresponding standards. If such problems cannot be avoided due to the light distribution of the lamps, they should be designed. Consider setting up the screen. The installation height of the luminaire should not be less than 3 m, and the bare lamp should not be placed in the line of sight.
4 summary
Based on the investigation of typical residential quarters in the main urban area of ​​Chongqing, this paper discusses and analyzes the requirements of road lighting level in residential areas and the choice of light sources and lamps. The main conclusions are as follows.
(1) The level of road lighting in the residential area surveyed basically meets the “City Standard for Urban Road Lighting Design CJJ45-91â€, but none of them meet the requirements of the current standard of lighting standards, especially the collecting roads, which are far from “ The lighting standard of the branch road has a direct relationship with the location of the residential area and the security environment. It can also be seen that in the specific residential area road lighting design, the adjusted lighting level is adjusted according to the actual situation. There may be a large gap between the higher lighting standard values ​​of the new standard.
(2) Most of the road lighting sources in residential areas use thin-tube fluorescent lamps or compact fluorescent lamps, which basically meet the requirements of the new standard. In the selection of lamps, most of them use non-cutting lamps, but they are all considered. Impact on neighboring residential buildings.
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