Engineers are conducting tests on a computer model of the 37-year-old Orwell bridge near Ipswich to determine whether the structure can be remain open to cars and motor bikes during high winds.
Previously, the bridge has been closed to all traffic during high winds causing serious congestion.
Over the next few months aerodynamic tests are to be applied to an advanced mathematical model of the bridge over the river Orwell, to examine how wind affects vehicles as the cross it during heavy winds.
The Orwell Bridge carries the A14 – a vital transport link for Ipswich – which has been plagued by closures during high winds because of fears about the safety of vehicles, especially high sided goods lorries.
The aim of the study is to determine whether small vehicles can be permitted to use the bridge during high winds, while high sided vehicles are diverted around it. This would reduce congestion in Ipswich.
Details of Orwell Bridge study have emerged following a Freedom of Information request.
City University assistant professor of structural engineering Alfredo Camara is leading the study, which he says will help to design new transport protocols.
“This project aims at developing a new numerical model in which the response of the bridge under wind load is combined with the response of the vehicles steered by the driver’s response,” Camara said. “This cutting-edge model is being implemented in Python [advanced programming language] and will be applied to the study of the Orwell Bridge to determine the wind velocities beyond which accidents can occur for different vehicle types. This will help the bridge operators to design efficient and safe traffic protocols.”
A Highways England spokesperson said the bridge was only closed when essential for safety reasons.
“We have been working hard with our partners in local authorities, the emergency services and business groups to reduce the number, duration and impact of closures due to severe weather.”
The total cost of the study will be £25,581.30, and it is being funded entirely by Highways England. It is set to complete its findings in summer 2019.
The details of the study come as plans for three additional bridges across the Orwell to ease traffic were scrapped with costs soaring from £97M to £139M..
The main tests for the mathematical model of the Orwell Bridge will look at:
- Influence of the wind and driving speeds.
- Influence of vehicle characteristics (exposed surface, loading, etcetera)
- Influence of the position of vehicles across the width of the bridge deck.
- Influence of road surface irregularities.
- Influence of the aerodynamic response of the bridge deck.
- Influence of a driver’s steering response.
Like what you’ve read? To receive New Civil Engineer’s daily and weekly newsletters click here.