October 2022 update

The final testing and investigation report from Taziker Industrial Ltd. has been reviewed by Design Consultants Pell Frishcmann, who have highlighted two areas of Taziker's work that has been inconclusive:

1. Strength of the lower stirrups that connect the timber beam to the suspension hangers.
2. Geometrical and condition information for the chain saddles positioned to the tops of all four towers.

The requirements and preliminary design for the refurbishment of the bridge are currently being considered by Pell Frischmann (Design Consultant) VolkerLaser (Specialist Contractor) and Blackett-Ord Conservation (Accredited Conservation Engineers), who will work together to update the cost estimates and progress into a detailed design.  

The project is on track to be completed no later than March 2024, as stipulated by the Levelling Up Funding.

Findings:

Further thought and detailed design is needed in the following areas:

Cross section of revised deck arrangement (currently under consideration)

Strength of the timber deck: 

To allow the bridge to reopen to vehicles and pedestrians, some of the materials used in the timber deck need to be improved along with a review of the layout and width of the deck.  This work is nearing conclusion and is then subject to approval by Historic England.

3D view of Lower Stirrup Arrangement

Strength of the wrought iron lower stirrups:

The shape of the stirrups has been accurately recorded and assessed and the results show that the stirrups are theoretically only just strong enough to hold the required load on the bridge. Plans are underway to remove some stirrups and load test them in laboratory conditions to confirm the assessment results and that no modifications are needed.

3D view of proposed adjustable hanger wedge

Vertical alignment of the timber deck:

The current vertical alignment of the timber deck is not favourable and therefore the deck needs to be levelled out over the full span to allow even distribution of the loadings.  This is how the bridge was initially designed.  In order to allow maintenance and tuning of the vertical alignment, alteration to the tapered wedge details shown in Image 2 is being considered.  Proposals include the addition of a height adjustable wedge as shown in Image 3.  This will be subject to approval from Historic England.