The traffic flow along the motorways in the Netherlands is gradually getting less because of an increasing use and an almost constant capacity. The accessibility of the economic centres is thus coming under heavy pressure. In late 2000, TNO Inro presented a solution that, in the meantime, is known as ''Bypasses for accessibility". The main feature of this concept is the introduction of an additional system of "underlying" main roads that can handle a large part of regional traffic thus relieving the existing motorway network. According to TNO Inro, their application results in a considerable improvement of the traffic flow and also contributes to a reduction in the number of traffic casualties. The Netherlands Association of Infrastructure Contractors VIANED commissioned SWOV to investigate whether it supports this result about safety effects. At the same time in this report, SWOV proposes that the road network introduced by TNO Inro should meet the requirements of a Sustainably-Safe Road Traffic.
Abstract