Pont Telpyn Bridge is a Grade 1 listed structure consisting of a single masonry arch span over the River Clywd. The bridge was subject to Cintec’s Archtec strengthening scheme during 2008 when a flash flood overwhelmed the structure and washed out a portion of the Western abutment foundation causing the arch to twist and deform and the bridge to become unstable. The road was closed and the parapets removed to relieve the load on the arch whilst a solution was sought. APB Group Limited were engaged being able to combine all the anchoring and civils and building skills required to restore the bridge.
A Synopsis of the Project is as follows:-
· Mobilise and establish site
· Divert River Clywd using approx 100 linear metre diversion channel & damming works complete with 24 hour pumping to maintain dry.
· Establish plant route onto river bed.
· Design and install propping to arch.
· Install and drive piles under the restricted height bridge soffit to protect propping foundation from undermining during abutment removal and foundation excavation.
· Complete archtec strengthening works.
· Demolish and replace complete West abutment in mass concrete using “underwater concrete” in foundation.
· Demolish and rebuild twisted section of arch span.
· Construct upstream head wall.
· Clad new mass concrete abutment with masonry to match existing.
· Remove Propping.
· Rebuild parapet walls.
· Construct new relieving twin culvert and relieving side channel.
· Install anti scour rock armour and gabion basket approach.
· Remove river diversion and damming works.
· Reinstate local fields and fences.