海角视频

Folkestone Harbour Viaduct and Swing Bridge

Folkestone, UK

海角视频 enabled the transformation of redundant Victorian railway infrastructure 鈥� a viaduct, swing bridge and railway station 鈥� to create a vibrant new pedestrian route, which has played a key part in the wider regeneration of Folkestone Harbour.

Folkestone鈥檚 location on the English Channel made it an important fishing town for centuries. Folkestone Harbour was originally constructed in 1809 by Thomas Telford and in the 1870s, its connection to the railway network was completed. Folkestone鈥檚 popularity as a holiday destination declined with the advent of cheap air travel and the 1994 opening of the Channel Tunnel, which further reduced the demand for cross-Channel ferry traffic from the town.

The site of the harbour and Harbour Parade changed from a bustling port with railway sidings and a Victorian Pleasure Pier in the 19^th century to a fairground with slides, rollercoasters and nightclubs in the 1960s and 1970s. Following the demise of these attractions in the 1990s, the site became a truck parking area for cross Channel traffic.

But in the 21st century, the Folkestone Harbour Company and a number of charities invested in the town to shape a new identity and purpose and deliver a significant regeneration. Sir Roger De Haan purchased the harbour in 2004. His vision was to develop the area into a high-quality residential and commercial development that will serve as both a legacy and a catalyst for further regeneration of the town where he was born.

Our team supported the transformation of an historic viaduct, swing bridge, railway line and station to form a new pedestrian route into Folkestone Harbour.

The entire structure was inspected and its load-carrying capacity assessed, taking account of its condition.

Repairs and modifications were then specified and designed for the viaduct section, including sympathetic new parapets to suit pedestrian use.

We designed a lightweight steel deck that allowed pedestrian access across the swing bridge and onto the viaduct, while carrying loads back to the original 鈥渟trong points鈥�.

Challenge

A multidisciplinary 海角视频 team, from across a range of disciplines, worked on the wider regeneration of Folkestone Harbour. In 2015 our infrastructure, bridge engineering and structural engineering experts were further engaged to work closely with architects ACME, Macfarlane Associates and John Leatherland on the refurbishment of the Victorian railway viaduct and swing bridge to create a new pedestrian route into the harbour, together with the transformation of the harbour鈥檚 redundant railway station, with the trackway transformed into a fully pedestrianised route.

The original timber swing bridge was replaced by a steel swing bridge in 1930. The pivot was later concreted up, making it no longer able to swing. However, the complete structure, including the original 180m, Victorian viaduct remained in service until regular train services to Folkestone Harbour ceased in 2001. The viaduct was Grade II listed in 2012.

Throughout our design engineering work on the project, we had to be mindful of retaining the heritage value of this historic piece of infrastructure and working within the constraints as dictated by the Grade II listing, whilst delivering significant interventions to enable it to play a new role in the town. Another key challenge for the swing bridge was the introduction of a new walkway surface on a structure that previously received railway loading, but only at very specific locations (i.e. below the rails).

Solution

The entire structure was inspected and its load-carrying capacity assessed, taking account of its condition. Repairs and modifications were then specified and designed for the viaduct section, including sympathetic new parapets to suit pedestrian use. Although the brickwork was in a relatively good condition, the impact of the tidal seawater and vegetation that had grown within the brickwork, meant the entire structure needed to be repointed and occasionally broken out and repaired.

Numerous repairs to the swing bridge steelwork were scoped, which required close coordination with the contractors on site, as much of the true state of the structure emerged only during the renovation works, as layers were stripped away.

海角视频鈥檚 experts designed a lightweight steel deck that allowed pedestrian access across the swing bridge that unlocked the remainder of the viaduct. This deck carried loads back to the original 鈥渟trong points鈥� of the bridge, made legible by the retention of the rails in the finishes. Our experts also supported the wider design team on elements such as the most resilient choice of paint specifications, given its seafront location, as well as overseeing the repairs to corroded areas of steelwork.

We worked with the landscape architects, Macfarlane Associates, to develop attractive solutions for sections of redundant berthing piers that run off the viaduct, designing tiered, stepped areas where visitors can pause and take in the views.

Similarly, our structural engineers were instrumental in assessing the existing state of the redundant station platforms and advising on the most appropriate, light-touch interventions to transform it into an attractive focal point for the regeneration. This included working closely with the contractor and local fabricator to ensure careful restoration and repair of the station鈥檚 historic canopy steelwork. Our team also developed a digital parametric model to work out the most efficient and impactful geometries for the new glazing above remodelled ends of station platform canopies.

The route through the renovated viaduct and former station complements the new network of footpaths and walkways around Folkestone鈥檚 harbour and seafront. The station and viaduct rail tracks have been preserved in situ, and asphalt has been added between the tracks where trains used to run to create public walkways with a coastal garden.

The viaduct and swing bridge have also been adapted for public use with a linear garden of naturally occurring and sturdy coastal plants in between the original tracks, and a new viewing platform sitting on the remains of two brick buttresses to the east of the viaduct.

Value

The Harbour Viaduct and station now provide an accessible route from the Harbour Arm to Harbour Square in the town, forming an important and attractive link in the redevelopment.

Our team played a key role in helping to ensure the success of this sympathetic regeneration, which has played a central part in the placemaking aspects of this newly revitalised area.