Case Study - Highways Agency: Risk Based Standards for Roads
In order to realise one of its strategic objectives to improve journey time reliability, the Highways Agency is assessing the feasibility of introducing Passively Safe Portal Signal Gantries onto the network. These will carry the electronic boards necessary to manage variable speed control and are thought to be cheaper than existing gantries which were designed to carry much heavier loads and require barrier protection to the supports.
To inform these considerations, Risk Solutions was asked to develop a risk model that would evaluate the impact of alternative gantry designs on safety risk, journey time reliability and whole life cost.
Over the expected life of the gantry, the model determines: safety risk to road workers, road users and the general public; journey disruption from lane closures during construction and maintenance activities; and capital and maintenance costs.
The model provides valuable insight into the factors influencing the risk associated with different designs and has been well received by the Agency. It is consistent with the Agency’s aspiration to move towards risk-based standards and has been incorporated into a new performance standard for Passively Safe Portal Signal Gantries.