Stapleton Road

Stapleton Road (reliefs deck) is a four-span masonry arch viaduct carrying two tracks of the Bristol and South Wales Union line (BSW) running between Bristol East Junction and Severn Tunnel Junction.  The superstructure consists of brickwork arch barrels with stone spandrels and parapets. The substructure consists of stone abutments, piers supported by spread footings.

Span 1 crosses over Stapleton Road, a key road within the Easton area of Bristol.  Span 2 crosses redundant land formally housing a garage business whilst Spans 3 & 4 span the previous route of the River Frome which was diverted during the construction of the M32.

The original structure was built in circa carried a single bi-directional line of the Bristol & South Wales Union line (BSW) and widened to its current form in 1872 to accommodate an additional track.  

Scope of services

Nuttall Bowser undertook repair scoping survey to establish repairs required to meet a 25-year major maintenance free period and achieve a condition rating BCMI score of above 60.  Nuttall Bowser subsequently undertook detailed design for repair and remedial works to various defects including ring separation within the arch barrels, spandrel wall movement and pier distortion due to settlement.  Nuttall Bowser provided construction site support to ensure scope completion and advise our clients on proposed repair methodology from defects arising from post de-vegetation works.

Challenges

The structure crosses uneven ground in the former River Frome spans and neighbouring properties to the downside of span 2 providing challenging access for survey works. Nuttall Bowser planned (including gap analysis) and carried out additional survey works to mitigate previous access limitations and obtain full defect survey information. Nuttall Bowser completed site works adopting both traditional sites on pre-drawn to scale pro-forma and photographic annotations via tablet photography to ensure accurate defect locations as well as validating previous surveys.      

Track access was not available prior to the initial design submissions and thus Nuttall Bowser provided detailed design based upon archive information and previous examination information which we validated and pinpointed through subsequent trackside surveys.  

Nuttall Bowser provided ‘findings report’ in order to communicate the compliance of both signage and parapets to current standards with recommendations for further enabling works and surveys to establish concept design for improved edge protection at and adjacent to the viaduct.

Value added

Nuttall Bowser were able to provide our clients with detailed site notes within a single working day following completion of site notes and an high overview on the day of examination. 

Nuttall Bowser responded to site support technical queries and were able to be present on site within a single working day from receipt of request for support and issue formal technical query responses within a single working day.  

Nuttall Bowser identified areas of further defects, previously hidden by vegetation during previous surveys, and advise our clients upon the additional design scope within a single working day, following site works, to ensure the additional works were agreed and could be planned and completed prior to the contractors demobilising from site and thus avoiding additional costs to the end client.