Frankham was appointed to inspect and identify structural elements, and to design remedial works, to the canopies at Fratton Station.
- Octavius Infrastructure Ltd
- Fratton, Portsmouth
Lack of technical data
A potential risk was the limited record drawings and data, and that no information was available on the condition of the structure. It was important for us to be cognisant of the load capacities and potential deformation of elements when changing load paths when load is transferred to the temporary works and then back again. Also, after the repair of the column base and the reinstatement of the repaired, previously cracked bracket.
Working in an operational rail environment
There were restrictions on working hours and areas during the site inspection, the installation of the temporary works and whilst carrying out the remedial works. These were in place to prevent disrupting normal station operation such as train operations, live services and the travelling public.
Lack of technical data
Frankham have professionally trained engineers who, through tactile and visual inspections, ascertained the construction and structural arrangement of the Victorian canopies at Fratton Station. Our engineers took measurements and produced sketches that enabled them to carry out the necessary calculations to provide a solution to the deteriorated areas of the canopy structure without compromising the rest of the structure.
Working in an operational rail environment
The inspection was carried out during night hours under line blocks by appropriately trained and protected engineers wearing prescribed Personal Protective Equipment (PPE).
Our design selection of the required temporary works and repair methodology, took into consideration the existing services and maintaining normal station operations. It also incorporated the specialist repair required for the cast iron bracket.
In order not to interfere with the station activities and travelling public in the construction sequence, the larger, temporary propping system could be dismantled once the cracked cast iron bracket was removed. A temporary steel bracket was installed to support the cantilever timber beam. The specialist nature of the repair of the cast iron bracket meant it needed to be sent off-site and it would be several months before it could be reinstated.
A two stage approach to the temporary works meant that the larger, more obstructive propping system was only in place for short periods. This effectively minimised impact on platform use and operations.
Retrofitting of the defective timber column and cracked, cast iron bracket in the Fratton Station canopies, delivers a sustainable solution.
Maintaining the ongoing structural performance and lifespan of the station canopies is a less wasteful and low carbon
solution compared with replacement with new structural members.
This project is part of a programme of maintenance and engineering works, managed by Network Rail, that utilises the £4.8 billion Levelling Up Fund launched by the UK government.
Investing in infrastructure will improve everyday life for communities across the UK, including the upgrade of local transport.
MEng (Hons) CEng MICE CMgr MCMI
