It is imperative that all systems for motorway tunnels be of the highest reliability. This may be achieved by having certain vital parts of a system duplicated with automatic changeover and 'hot-standby' configurations. Another approach is for the systems to be designed and constructed such that they are 'fault tolerant' and hence can continue to operate when one or more minor faults occur. One area that has ca270d much controversy over the years and is still the subject of much debate is 'should various systems be integrated or independent'. There are tunnels where various systems have been integrated and controlled from one single or dual processor system. The main advantage of these was the reduced capital cost at the time of installation, however this has been offset in many instances by the difficulties in maintenance or modification of one part of the system without causing disruption to other parts. Rapid developments in microprocessor based control equipment have now made it viable to divide systems into logical sub-units and equip these with relatively low-cost micro processor based control equipment, all sub-units being linked to an overall control/monitoring equipment, with easy means of disconnection as and when required.
Special features of traffic monitoring and control on recent motorway tunnel projects
Spezielle Merkmale der Verkehrsdarstellung und Steuerung bei neuen Autobahn-Tunnelprojekten
1986
5 Seiten, 3 Bilder
Conference paper
English
Traffic monitoring and control in motorway tunnels
Tema Archive | 1986
|Motorway traffic control system
Tema Archive | 1984
|TIBKAT | 1976
|Engineering Index Backfile | 1959