This research project investigated the use of curve advisory speed signs in New Zealand. A literature review identified key issues to examine.
Current traffic behaviour at the location of curve advisory speed signs was observed in order to determine effectiveness and compliance.
Alternative methods for determining curve advisory speeds, using road geometry data or accelerometer-based systems, were compared with ball-bank surveys.
The existing criteria and methods used for setting curve advisory speeds in New Zealand were assessed in light of the above findings, and changes suggested.
Keywords: horizontal curves, rural highways, advisory speed signs, New Zealand