Steelwork faults shut Forth Road Bridge
The restrictions have already caused major disruption to one of the country’s key transport routes and further inspections have identified eight other parts of the bridge where similar problems could occur.
Additional rail capacity was put on overnight and a full travel plan is being prepared for the duration of the closure.
Timescales could be affected by adverse weather conditions.
“The bridge is to shut following the discovery of defective steelwork earlier this week”.
A tweet from the Forth Road Bridge account also read: “New weight restriction on bridge”.
They said that continuing to allow traffic to use the bridge would “increase the risk of causing extensive secondary damage to the structure”.
Inspectors for maintenance contractor Amey are said to have found the problem during a routine check of the Forth Road Bridge in Scotland.
A ScotRail spokeswoman said the firm was looking at putting on more trains or extra carriages.
Mr Mackay told the BBC Good Morning Scotland programme: “It’s important, on the expert advice we’ve had, that we get access to the site”.
Strong winds on Friday and across the weekend close the bridge to all vehicles apart from cars, with the road to be closed completely for a short time around midnight on Friday into Saturday.
“This is a complex engineering challenge”.
“We continue to work around the clock on inspections, assessments and calculations along with the development of designs to effect the necessary repairs, while at the same time mobilising all the resources required to reopen the bridge as soon as is possible”.
A new bridge – the Queensferry Crossing – is due to open over the Firth of Forth next year, costing the Scottish Government up to £1.4bn.
Messages posted on Twitter from the Forth Road Bridge operators at the start of the day’s commuting peak warned of “very long delays” on the northbound and southbound approaches.
It transformed the journey between Edinburgh and Fife but now carries 24 million vehicles a year over the Forth, which is far more than it was created to handle.