DRUIDS ? Prophecy or Heresy for Solving Congestion at At-grade Arterials Intersections?
U Bezuidenhout, S McMillan, GHD Limited, UK
DRUIDS is a modified Displaced Right Turn Junction for commercial and retail land use to facilitate access and public transport movements whilst significantly increasing traffic capacity and improving pedestrian safety around large retail nodes.
DRUIDS (Displaced Right tUrn Intersections for DevelopmentS) is a novel approach using a modified form of a continuous flow intersection (CFI) that can reduce complex traffic movements around large traffic generators adjacent to at-grade intersections.
Previous research studies have shown how a CFI can decrease the overall delay and queue lengths from those of a conventional intersection by 64% and 61% respectively. This modified form of a CFI will improve efficiency and safety for intersections that handle well over 100,000 vehicle movements per day.
A case study will be presented which compares an existing high volume at-grade signalised junction (+80,000 vpd) located in Auckland, New Zealand that dissects 4 large retail/entertainment developments in each of its quadrants, to a DRUIDS intersection. This unconventional form of intersection arrangement is a solution to integrate land-use and transport networks in a manner that reduces the footprint at the intersection. It reduces the pedestrian crossing distance by re-locating turning movements, property and transit access to minor roads off the arterial, thus enhancing both mobility and accessibility.
A traffic simulation model will be used to demonstrate and quantify the efficiency gain of changing the at-grade intersection of Ti Rakau and Te Irirangi Drive to a DRUIDS layout.
This modification reduces conflict and complexity at high volume at-grade intersections. It will demonstrate how a DRUIDS approach can be incorporated to serve the retail nodes by dissipating the high volumes of entering and exiting traffic near the junction itself, thus increasing safety and efficiency.
Association for European Transport