Due to financial and technical considerations, the design of road tunnels often differs from open road design. Standards are applied more loosely, which leads to suboptimal design solutions in terms of traffic safety and comfort. This may affect the level of driving safety for instance if the design provokes sudden changes in driving behaviour, and does not permit sufficient anticipation. This literature review provides an overview of the effect of tunnel design characteristics on road user behaviour, and can serve as a basis for recommendations on specific tunnel design standards. The focus in the literature review is on tunnels on motorways. Tunnel entrances are of special interest, since they confront road users with the transition from open roads to tunnels. The most prominent change is the transition in the amount of luminance. Large differences between the luminance level outside and inside a tunnel should be avoided in order to avoid adaptation and perceptibility problems. Luminance differences can be minimized by increasing luminance inside and decreasing luminance outside the tunnel.
Abstract