Trusses provide sports legacy

An array of different sized trusses are needed to create the column-free spaces for Sunderland’s Beacon of Light sports and education facility. Martin Cooper reports.

FACT FILE
Beacon of Light, Sunderland
Main client: Foundation of Light
Architect: FaulknerBrowns Architects
Main contractor: Tolent Construction
Structural engineer: s h e d
Steelwork contractor: Harry Marsh [Engineers]
Steel tonnage: 880tAn education and sporting facility with a difference is under construction in Sunderland. Known as the Beacon of Light and located adjacent to the city’s famous Stadium of Light football ground, the centre is said to be the first of its kind in the UK and will include engaging and interactive zones for education, health and fitness, as well as sport.

The Beacon is also the final project of the wider regeneration of the former Monkwearmouth colliery site. Other projects on the site, as well as Sunderland FC’s stadium have included a hotel and an aquatics centre boasting a 50m competition pool.

Built over five-storeys and occupying 4.75 hectares, the Beacon is a large cube-shaped structure which will be illuminated at night. The upper areas will be clad with transparent polycarbonate cladding, light from within the structure will seep out creating a highly visible beacon [hence the name] on the city’s landscape.

“Steel has been chosen for the Beacon of Light to enhance the concept of a simple lightweight enclosure over a brick base. This is of particular importance within the polycarbonate enclosed football barn where the primary and secondary structural elements remain visible.”

Here, connections have been designed carefully to minimise visual impact and painted hot-rolled box elements have been used to create an unimposing support frame. The use of steel in the roof provides a strong but lightweight solution, maximising light penetration through the fabric covering creating a glowing beacon effect at night,” says Paul Reed, Architect, FaulknerBrowns.

The Beacon of Light, pictured in foreground, with the aquatics centre and Sunderland FC’s stadium behind. (Photo: David Allen)

The roof trusses spanning the football pitch

Temporary trestles support the roof trusses during installation

Trusses span the sports hall and support the football pitch above

At ground floor level the building will accommodate a large multi-use sports and performance hall, adjacent to which sits a four-level teaching and learning block. Above this, and topping the entire structure, is an indoor 4G football pitch.

“Structural steelwork was the obvious choice and it is the only material that could form the building, particularly the trusses, cost-effectively and efficiently,” says s h e d Director Marc Horn.

There are a lot of trusses in this structure! Working from top to bottom, the uppermost and longest trusses, at 60.5m-long, are the nine that form the Beacon’s roof, creating the open column-free space for the third-storey football pitch.

They are fabricated from structural hollow sections, 150mm × 150mm × 10mm top boom and 200mm × 200mm × 8mm bottom boom. The top boom was pre-cambered for steelwork contractor Harry Marsh [Engineers] by specialist bending company Angle Ring.

The trusses are 4.1m-high and weigh 13t each. They needed to be brought to site in three pieces and were erected individually using Harry Marsh’s on-site mobile tower crane (pictured above).

“It’s a two-way spanning roof, as connecting the main trusses is a set of secondary trusses formed from secondary members,” says Mr Horn. “This design proved to be more efficient and lighter.”

Because of this design, each truss, during erection, was supported at third points by two temporary trestles. These had to stay in position until the entire series of nine roof trusses and their connecting steel members were in place, thereby making the entire structure stable.

The main structure of the Beacon is formed with UC section columns up to the underside of the top floor. Above this point, a series of SHS vertical trusses, up to 4.8m high and measuring up to 21m in length, form the football pitch area’s elevations and support the roof trusses.

Moving down the structure, another two series of trusses were required to create the column-free space for the multi-use sports and performance hall, as well as the areas that overlook it.

Spanning a distance of 34.7m and each weighing 13.7t, nine 4m-high trusses form the hall’s roof and support approximately half of the floor for the football pitch above.

They were brought to site in three sections, and then bolted up to form two larger pieces, consisting of one third and another two thirds element. Using two mobile cranes, they were then lifted into place, with the final connection between the two pieces being completed while they were being supported by the cranes.

These trusses are supported at one end by the building’s perimeter columns, and internally by another series of three spine trusses.

The storey-high spine trusses are positioned in a row, at second floor level, across the building’s width, effectively forming the demarcation between the sports hall and the teaching zone.

As well as supporting the sports hall trusses, these multi-purpose spine trusses also support three levels of structure and allow the first floor below to have just two columns within the viewing gallery overlooking the sports hall.

The gallery will be used by spectators during sports contests and concerts. More spectators can be accommodated on moveable bleachers (stands), which can be stored when not in use in a recess beneath the first floor.

The three-level accommodation block is formed around a semi-regular 6.75m grid pattern, which also corresponds with the set-out pattern for the project’s trusses.

“A number of discussions were held about the grid as it has to accommodate classrooms, offices and work spaces,” sums up Mr Horn. “The chosen column spacings proved to be the most efficient for all of the intended uses.”

Who are the Foundation of Light?

Established in 2001 by former Sunderland FC Chairman Sir Bob Murray, the Foundation of Light [FOL] seeks to use the power of football to change the lives of young people, via sports, health, community and educational schemes.

While the FOL is linked to its neighbour Sunderland FC, it is structurally and financially independent. It is responsible for fundraising £4M every year to run its life-changing programmes.

The Patron of the Foundation of Light is Her Royal Highness The Countess of Wessex. The list of Trustees, which includes Sir Tim Rice, also reads like a who’s who of local north east personalities with athlete Steve Cram, news reporter Kate Adie, cricketer Paul Collingwood and TV presenter and architect George Clarke.