Police are investigating the crash and say no arrests have been made.
The bridge will close on Tuesday night and again for 12 hours on Sunday while work is carried out.
As the OU in Wales marks half a century, two alumni explain how it helped them.
Cardiff Blues head coach John Mulvihill says Gareth Anscombe will be involved against his future region Ospreys in Saturday's vital Judgement Day fixture in the Pro14.
Wales stars Alun Wyn Jones and George North could return for Ospreys in Saturday's crucial Pro14 match against Cardiff Blues.
South Wales Argus
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