It is the aim of the ramp-metering part of the project to use the existing expertise to identify the applicability of existing approaches. Apart from a desk-top comparison like the deliverable just cited, two field trials were planned: a field trial with ALINEA (Asservissement Linéaire d'Entrée Autoroutière) at the Coentunnel in Amsterdam, The Netherlands; a field trial with the Woottori Jeffrey's strategy on the BP in Paris, France. These trials should lead to insight in the range of conditions over which the approaches are viable, the limits of the applicability of isolated control and possibly lead to control improvements. The results of the trial in The Netherlands are reported here. So this document discusses the way in which the Coentunnel trial was setup, implemented, tuned, tested and assessed. The ALINEA-strategy is based on occupancy which is measured downstream of the ramp. The RWS-strategy is based on flow upstream and on speed both upstream and downstream from the ramp. The results show to be in favour of the ALINEA-strategy. ALINEA increases the total service of the system, the motorway and the ramp at the Coentunnel. When homogenisation of the traffic flow is important, the greater deviation of speeds with ALINEA is of importance. (Author/publisher)
Samenvatting