THE ARENA SHOWS THE POWERFUL BENEFITS OF 3D MODELLING
Wilkinson Eyre's vast Liverpool Arena and Conference Centre is the practice's first project designed primarily in 3D - an approach that led to myriad complexities.
A stadium is not the first building type that comes to mind when one thinks of an inviting public realm and a vibrant pedestrian neighbourhood. Yet these were defining aspects of the brief put to Wilkinson Eyre for the £118 million Liverpool Arena and Conference Centre, due to open in January for the city's inauguration as European Capital of Culture 2008. Wilkinson Eyre's first response was to re-site the building within EDAW's 14ha Kings Waterfront masterplan, moving the stadium from its initial inland location to the water's edge. This makes ultimate urban design sense. The stadium's massing and height take their cue from the adjacent Albert Dock, and its dramatic form will undoubtedly make the arena the latest landmark on the Liverpool waterfront. The more challenging part of the brief was to create an attractive pedestrian approach from the nearby city centre and reclaim the site's waterfront as a place for human activity.
The arena will primarily act as a music venue, and the public piazza will host outdoor events. It is designed as a box within a box, to meet stringent planning regulations that require no increase in background noise levels. Kings Waterfront will be a mixed-use community that includes residential, office, retail and outdoor spaces, plus two hotels. Both daytime and night-time approaches to the venue have been carefully considered.
The Liverpool arena complex marks a significant innovation for Wilkinson Eyre because it is the practice's first project designed primarily in 3D - a design approach which ties into the scheme's urban-design objectives as well as facilitating detail design, tendering and construction. Director Oliver Tyler describes the approach as 'more akin to product design' - an iterative process of moulding and shaping the building to the site and the programme, 'squeezing the building to its tightest possible form to reduce its bulk and cost.' The building's owing forms respond to pedestrian movement. Tyler compares the views of the building as one approaches to 'a glimpse of a liner parked at the end of a terrace between rectilinear industrial buildings'.
A key decisions early on was to bury the 10,000-seat horseshoe arena bowl 3m below grade to reduce the bulk of the building. The public will enter at mid-concourse level. All services are located either below grade or within the curvature of the roof - the steel trusses are 6m deep - to minimise dead pedestrian zones at plaza level and mechanical protrusions through the roof. The conference centre, with its 1,350-seat auditorium and 7,600m 2 of exhibition space mirrors the form of the arena, and the two are connected by an ETFE-covered gallery.
The cladding has been the subject of intense design scrutiny in order to achieve visual interest by both day and night, to break down the scale of the building and to control costs within the constraints of a limited budget. Horizontal bands of glazing with differing degrees of transparency - transparent at plaza level, and translucent above, with sandwich panels at the top - reveal the drum-like forms of the arena and auditorium, which serve as orientating devices with exteriors painted in deep cobalt blue and silver. The 3D model meant that the surface area of the building could be established early on to explore and cost different cladding options.
Acoustics were a driving factor in the specification of the exterior envelope, and led to the eventual selection of a Finnish cassette system by Ruukki for the roof. Acoustic isolation was ensured by a continuous 1m-deep air gap between the upper and lower roof skins. The translucent banding on the facade started as faceted Kalwall but was replaced by fritted glazing for acoustic reasons. The ratio of rainscreen cladding to translucent glazing was fine-tuned in several iterations in order to meet cost constraints. Double curvature in the original model has been resolved through the use of at and folded metallic-grey sandwich panels, all 1,000m wide with varying lengths. The curve is accommodated through the joints.
The story of the different computer platforms used during the design, tendering and construction of the Liverpool arena highlights the powerful benefits of 3D modelling, but also points to the accompanying pitfalls which the current trend towards building information management is trying to eliminate - or at least reduce. Wilkinson Eyre associate Sam Wright explains that the project was only made possible with 3D modelling. The practice produced a 3D model in 3D Studio Max which was used by the other consultants and some of the subcontractors in a range of software. There was a direct interface with Buro Happold's XSteel structural model and with WagnerBuro, the Austrian cladding supplier. This was facilitated by Wilkinson Eyre's Ivan Subanovic.
It comes down to people skills in the end.
With complex buildings of this type it is becoming essential to communicate in 3D, and therefore the systems need to become more standardised. Differing levels of 3D capability across the project team impact the patterns of information ow, which in turn has implications of providing a clearly auditable route. This also has a ripple effect on the workload of the different members of the project team. Subanovic comments: 'The ball is really in the court of the software producers. They are all fighting for a corner of the construction market and there is no clear standard established. We have different expertise within our office than the contractors and subcontractors have. There's definitely a job out there for someone to market these products and train teams up.'
A comprehensive 3D model at tender stage is the promise of the not-too-distant future, but its potential will only really be unleashed when enough standardisation occurs across the industry, so that ready interface with contractor and subcontractors becomes the norm.