NATIONAL TECHNICAL UNIVERSITY OF ATHENS
School of Electrical and Computer Engineering
Electrical Power Division
DIPLOMA THESIS
ROAD TUNNEL LIGHTING DESIGN
ACCORDING TO CIE 88-1990 USING A COMPUTER
DIMITRIOS P. CHIKIMTZIS
SUPERVISING PROFESSOR
FRANGISKOS V. TOPALIS
ASSOCIATE PROFESSOR, N.T.U.A.
THE PURPOSE OF ROAD LIGHTING
The main purpose of road lighting is to improve road safety at night by providing good visibility for road users. Properly designed road lighting can create an environment, at night on open roads and during the day in tunnels, in which drivers are able to identify the edges of the road promptly and accurately, as well as any obstacles and objects ahead of them on the carriageway, so that they can react safely.
Road lighting installations also aim to achieve smooth traffic flow by giving a clearer picture of the geometric and traffic characteristics of the road and by allowing safer overtaking. In this way the infrastructure can be used to best effect at night, and in tunnels during the day, in a wide range of weather conditions.
A lighting installation must enable the driver to determine:
1. The condition of the road over the section to be travelled in the next 5 to 10 sec.
2. The position of the vehicle and its movement over that section.
3. The position and movement of other vehicles that are already using, or about to use, that stretch of road.
4. The presence of any obstacles on the carriageway in that section.
5. The road signs and markings.
In this way the driver of a moving vehicle can take in enough visual information about the constantly changing view ahead to proceed safely at a reasonable speed, and to react in good time to signs and markings and make the right manoeuvres. The aim of the lighting, then, is to create a bright environment and to maximise the luminance contrast between objects and the surroundings against which they are seen.
Analysis of various studies has led to the conclusion that deaths and injuries in road accidents at night can be significantly reduced if good lighting is installed in the following critical areas of the road network:
– roads with heavy traffic.
– junctions.
– entrances
– motorway exits.
– tunnels and underpasses.
– bridges.
– toll stations.
Road lighting is an important factor in the safety and efficient operation of the road network, provided that it is effective, that is, that it meets the requirements of the national and international standards that ensure the quality of the lighting system.
SUMMARY
Tunnels incorporate a large number of electromechanical installations, mainly concerned with the safety of users. These are lighting, ventilation, exhaust gas detection, fire detection, fire suppression, closed-circuit television, emergency telephones, signalling and vehicle height control. Of these, the most energy-intensive are lighting and, in long tunnels, ventilation.
Taking into account the construction programmes of the Ministry for the Environment, Physical Planning and Public Works (ΥΠΕΧΩΔΕ), it is estimated that Greece currently has more road tunnels under construction or out to tender than any other country in the world.
It is therefore essential to manage rationally the electricity used around the clock. A sound design, combined with proper construction and adjustment of the lighting, can contribute significantly to saving electricity used for lighting (by as much as 80%).
Part of our study involves making use of natural lighting. This is made possible by the ADELINE program.
This thesis is therefore a specialised study of road tunnel lighting using the ADELINE software, as well as the specialised tunnel lighting programs DPTunnel and TULIP (TUnnel LIghting Program).
Chapter 2 looks at the projects currently under construction in Greece, those already built and being opened to traffic, and those out to tender. It also presents Greece’s overall world ranking in terms of tunnel length.
Chapter 3 covers the basic photometric quantities, how the human eye works and how it reacts to lighting.
Chapter 4 analyses the basic principles that must be taken into account in order to achieve good lighting and economical operation.
Chapter 5 describes the various lighting systems available and gives the advantages, disadvantages and use of each.
Chapter 6 sets out the road tunnel lighting specifications according to CIE 88-1990 (International Commission on Illumination).
Chapter 7 provides information on the ADELINE program. The program is applied and its results are presented. The method of saving energy by using natural light in tunnels is analysed.
In Chapter 8, the specialised tunnel lighting program DPTunnel (lighting design) is run, and we get an impression of the TULIP (TUnnel LIghting Program) software.
Chapter 9 deals with lamps, luminaires, meters and tunnel lighting control systems.
In Chapter 10 we close with proposals and strategies that we need to implement in Greece in order to meet our country’s growing energy demands.
The thesis ends with two appendices: the first calculates veiling luminance, and the second discusses the longest road tunnel in the world and the lighting innovations applied in it.
