When the Queensferry Crossing opened in August 2017, it was claimed the bridge would not be closed by high winds as barriers had been installed to protect it from high gusts. Sadly since the opening problems have emerged, with wet snow building up and falling, in some cases breaking car windshields.
During design of the Queensferry Crossing these type of problems were understood but the decision was taken that would be managed by developing appropriate operational practice, in line with “practice at the time on similar bridges elsewhere in the world”.
After a number of different solutions being considered over the years the decison is that the bridge will have to be closed when the bridge is deemed to be unsafe to cross. Therefore the focus has been on how to monitor the bridge conditions and when its deemed unsafe how do you divert traffic quickly.
Norwegian-company, KVT, have developed and installed 2,000 sesnors which provide real-time analysis of the conditions impacting on the crossing allowing Bear Scotland to decide when to divert traffic away from the crossing.The challenge then remained that the actual process to divert traffic could take up to 6 hours resulting in the need to divert traffic to the Kincardine Bridge for any short term needs.
A better solution would be to install automated barriers so that traffic could quickly be diverted to the Forth Bridge and this work continues this week.
With foundations now in place, Transport Scotland’s operating company BEAR Scotland is installing the barriers. This requires work on the verges and central reservation of the M90 on both sides of the Queensferry Crossing, as well as resurfacing works on the hard shoulder of the slip road onto the southbound M90 at Junction 1B Ferrytoll.
All works will take place at night to minimise disruption. During the day there will be two lanes running in each direction at all times. Access for emergency vehicles will be maintained.
Resurfacing of the Ferrytoll southbound on-slip hard shoulder took place on Monday night. Verge barrier installation will commence on Monday, October 2, for two weeks, and central reservation barrier installation on Monday, October 23, for two weeks.
To test the barriers, the M90 northbound carriageway will be closed between Scotstoun and Ferrytoll from 10pm to 5am on Tuesday, October 31, with northbound traffic diverted via the Clackmannanshire Bridge. The southbound carriageway will then be closed between Ferrytoll and Scotstoun from 10pm to 5am on Wednesday, November 1.
A trial deployment of the barriers will be carried out on Saturday, November 4, to ensure they are operating correctly. The Queensferry Crossing will be closed in both directions from 11pm until 5am with all M90 traffic diverted via the Forth Road Bridge. Road users should expect delays at the beginning and end of this period as traffic is stopped while the diversion is implemented.
