Light Distribution Optimization And Light Environment Design Method Of Overpass Illuminator

Overpass is an important means to alleviate urban traffic congestion.The effect of the overpass lighting environment is related to the safety of drivers driving at night.Too low illuminance or brightness level,inappropriate brightness uniformity range,and excessive glare will affect the visibility of identifying targets and obstacles,reduce visual acuity,and cause traffic accidents.As a special road,the design of the lighting environment of the overpass is difficult:(1)The multi-layered spatial structure makes it impossible to create a good light environment through the pole lighting along the lane;(2)The multi-directional non-interference structure makes the driver’s sight line The direction is changeable,and it is difficult to reduce or control the glare within the full bridge deck.Relevant research results show that the average brightness of overpass bridge decks in my country generally meets or approaches the current national standard limit,and the threshold increment of the overpass glare evaluation index(Threshold increment,referred to as TI)exceeds the current national standard limit.Therefore,exploring the design method of the overpass lighting light environment has good theoretical and practical significance for improving the visual acuity and driving safety of drivers at night.This paper firstly analyzes the influencing factors of the threshold increment,uses genetic algorithm and particle swarm algorithm to optimize the light distribution characteristics of high-pole lighting fixtures,and then proposes an overpass lighting light environment design method based on intelligent algorithms,and passes DIALux The evo simulation has been verified,and the main contents include:a)Theoretical analysis of the changing trend of the observation angle,the vertical surface illuminance at the human eye and the average illuminance of the observation area with the angle between the incident direction of the light and the vertical line during the driving process of the motor vehicle,and the discussion of the threshold increment exceeding the national standard limit on the full bridge deck Circumstances,through global sensitivity analysis of the influence of each factor on the threshold increment,and verified through field tests and simulation experiments;b)Analyze the influence of the relative position change of the driver and the lamp on the evaluation index of each lighting environment in the case of a single glare source,and establish the goal of maximizing the ratio of the average brightness to the average illuminance of the bridge deck observation area,with the average brightness(illuminance)and uniform brightness An optimization model with constrained conditions such as intensity(illuminance uniformity),brightness longitudinal uniformity,and threshold increment,and proposed a genetic algorithm-based overpass lighting environment design method;c)The overpass model is constructed through parametric modeling,the correctness of the design method is verified by DIALux simulation,and the method is applied to the simulation of asymmetrical overpass lighting environment to verify that the design method is also applicable to asymmetrical overpass.