CD 116 Geometric Design of Roundabouts - research to support changes to design standards

Highways England (the Client) is seeking the provision of services to build on the previous research outcomes into roundabout approach arms undertaken in 2020/2021. The aims of this task are as follows: - To build on the outcomes from research undertaken in 2020/21 specific to roundabout approach arms. To gain an understanding of why most collisions at roundabouts on the APTR occur on the approaches. To check and challenge the existing geometric parameters in CD 116 for approach arms, and whether more robust requirements and advice can be established; and - To check and challenge if changes made as part of the DMRB 2020 style specific to signal-controlled roundabouts represents best operational practice.