Stand and deliver
Going to a Test Match at Lord's owes much more to a five-day boat cruise than to the short, sharp, sweaty, jostling experience of Highbury or Stamford Bridge: it's like boarding an ocean liner laden with food, drink, picnics, suntan lotion and fellow passengers. On the upper promenade decks it is all mcc ties, panama hats and tropical suits, where stewards greet you and usher you to your cabin. Down in steerage you put on a silly hat and T-shirt and open up the cool box . . .
Functionally the similarities are striking, and it is no accident that recent stands are full of transport metaphors: billowing sails, aerofoil wings, schooner masts, stealth-bomber curves and riveted boiler plate, all very firmly rooted in dry dock. The Grand Stand, designed by Nicholas Grimshaw and Partners, is another fine example in this vein.
Its predecessors, the Tavern Stand and the Mound Stand followed the same cruise liner format. Below decks is the mass seating: shoulder-to-shoulder seats (4000 in the Grand Stand) raked above subterranean bars, sandwich and hamburger stalls . . . and the engine rooms. Above are the hospitality boxes (25 in the Grand Stand, including two double boxes) with their own dining rooms and a brilliant view of the game or action replays on tv. Above the boxes are the upper promenade deck and first-class debenture seats (2000 in the Grand Stand), with bars and restaurants close at hand, but without a view of the game while you eat.
Dave Harriss, Grimshaw's project director, acknowledges the same starting point that we at Hopkins had used for the Mound Stand ten years earlier: the notion of Lord's as England's biggest village cricket green, a collection of diverse, self-contained buildings around it, resisting the conventional extruded stadium form, and stratification of accommodation in layers. Grimshaw also looked at many different cross-sections and concluded that it was difficult to improve on the Mound typology within the general height restraints.
The village green metaphor was an attractive one and probably at its most convincing in the early 1960s, before the Tavern Stand was redeveloped: apart from Verity's Pavilion, there was a pub with some seating on the roof, a ramshackle earth mound, a sort of third-division football stand, a 1950s stand (with more sloping walls, floors and ceilings than Zaha ever dreamed of), and Herbert Baker's imperious 1920s Grand Stand. The latter was as near as English architecture ever got to Albert Speer in a tweedy sort of way, mixed with a hint of New Delhi and the Cape of Good Hope. It was a pompous building with the most hopeless sightlines for spectators. It had character, but its functional inadequacies made listing hard to sustain.
While the thinking and the logic are impeccable, the problem with a new building in exactly the same format as the new Mound Stand is that it breaks down the quirkiness of the collection of buildings. If the format is the same, it begs the question of why the architecture is not the same. One hankers for something completely different in concept. The Grand Stand seems to acknowledge this dilemma by making a full-blooded effort to be as different as possible through sheer technical prowess. The roof spans are bigger and the mast taller, the roof covering is a wing and not a sail, the upper decks are built as bridges and not boat hulls, and the spectator terrace is moulded concrete rather than engineered masonry - almost studiously ignoring the earlier solutions. The Grand Stand's situation and brief do, however, create some particular problems that are not present on the other side of the ground.
Firstly, its rear wall, which is right on the boundary, had to be blank to protect the privacy of neighbouring houses, and it also has stairs behind the accommodation rather than within it. Both these factors hem in the rooms at the rear of the stand and deprive the building of the sort of urban and street presence that Roman arenas exploited so well.
Secondly, the site is a 100m straight line, which offers none of the characteristic curves of stadium structures, but did present the possibility of some really large spans.
Thirdly, in the quest for spectator numbers there are ten rows of debenture seats at the top of the stand, with restaurants below rather than behind the seating; this makes it the highest stand in the ground, nearly to the point of dwarfing the Pavilion, and consigns the restaurants to a view through frosted glass
Lastly, accommodation under the lower terrace is partially sunk underground and the road is much more enclosed than on the opposite side of Lord's, a result of the famous slope from one side of the ground to the other.
The challenge that Grimshaw set himself was to build two 50m spans for the upper floors and roof, supported on just three columns, giving the stand a very horizontal feel. The functional justification for the long spans is to reduce the number of columns passing through the spectator area and minimise the number of seats with obstructed views. At the back of one's mind there is a nagging feeling that it is perverse to ignore shorter spans or more conventional cantilevers from the back, but, putting this to one side, the engineering does rise to the challenge and it is realised convincingly.
It consists of a muscular two-storey-high steel spine truss running along the centre of the stand, with steel A-frames cantilevering out under the upper seating and suspending the boxes below, with slightly more weight on the pitch side which is counteracted by tie-downs in the rear wall. The roof is suspended by hangers from a central mast - which also provides a flagpole of fantastic proportions - through an elegant prismatic truss supporting a wing structure tied down to the deck below. The whole structure is post-tensioned, assembled on site from a number of smaller components, and the roof and upper superstructure were jacked up into position and prestressed in a very sophisticated operation.
The simplicity of the finished object belies a very complex interaction between differing structural elements. It is really bridge engineering, and this means that the very large scale of some of the structural members running through the occupied spaces is sometimes disconcerting. The metaphor of the aerofoil roof is curiously mixed with one of a sailing mast, in a way that would only happen in buildings and never in marine or aero engineering, but who cares? It has one beautiful touch: the 'flap' awnings extending from the leading edge of the wing that successfully conceal their origins as standard shop awnings.
While the impressive spans are well identified by three columns picked out in white, their impact is lessened by the obscured glass screens along the back of the stand that fill in the vital gap. It is only close up that the full effect is felt.
The below-decks accommodation is a bit claustrophobic, with internal corridors, windowless bars and a restaurant whose view is thwarted by opaque glass. The spaces are criss-crossed by spars and bulkheads and are not uplifting, but they are true to type in the cross-channel ferry idiom, with every nook and cranny of the structure colonised for one reason or another.
The architectural detailing of structural elements is of a very high order and the moulded precast concrete and welded steel structure are well thought out. There is a sleekness of styling that is surprisingly different from the straightforward and functional detailing of the Mound, even though John Thornton of Arups was the engineer for both stands. Apart from the different architects, it also reflects the way that the state of the art has moved on in the intervening ten years.
In contrast to the refinement of the structure, the rainscreen cladding systems and glazing to the rear of the stand, though not very visible, are definitely designed down to a budget. Services, particularly drainage, are always difficult in stands which have few forgiving voids and cavities in which to hide them. Vacuum drainage is a big breakthrough that should provide much greater freedom, but it is disappointing that it still exits visibly through the end walls, along with cable trays and ventilation ducts which escaped the discipline that the architect sought. But these criticisms are minor compared with the overall single-minded achievement of realising a unique and elegant structure with such conviction.
John Pringle is a director of Pringle Richards Sharratt and was the Hopkins director for the Mound Stand at Lord's
From the earliest days the Grand Stand design was shaped by the need for the building to be constructed during two short closed cricket seasons. This, combined with our need for quality control, led to prefabrication in both steel and concrete and enabled work on site to be limited to the final assembly of prefabricated units as much as possible.
Phase I (the ground-level terrace) consists of an interlocking assemblage of precast beams, terraces and slabs supported on in-situ columns on a grid about 7m square. The foundations for this level consist typically of single 600mm-diameter piles under each column. The three main columns, which support the second-phase superstructure, have separate piled foundations: four 1.8m-diameter, 40m-long piles for the central 1500-diameter column and two 1.2m-diameter, 35m-long piles for each of the end columns.
Critical to Phase II was the spine truss, which enabled us to free span the entire building over 2 x 50m. The span to size/weight ratios required (to conceal the truss in the building) were such that the truss could only ever have been steel. Initially we used steel frames off this truss to support precast infill floor slabs. But this evolved so that the precast floor slabs replaced some steelwork to become part of the primary structure. The result is that the materials vary as the manner of the force dictates (tension in steel and compression in concrete).
This interlinking required us to fabricate large steel connection nodes and cast these into the concrete to millimetre accuracy. Most elements in the 100m-long, three-storey structure fitted together with several other elements, so accuracy of fabrication was absolutely vital. At the same time other elements of the stand were prefabricated, most notably the 270-tonne, 100m-long spine truss which was fabricated in five sections (max 26m x 6m x 60 tonne) to be site-welded together in location. All this work was carried out during the open cricket season after completion of Phase I and prior to work on site commencing for Phase II. Erection of Phase II was carried out with all levels supported on temporary works, and it was only when the main structure was complete and able to restrain the spine truss that the building could span the 100m. Depropping the ~2700-tonne Phase II took three weeks and used 82 90-tonne jacks which were controlled and monitored from one central computer.
Above the main structure, the roof consists of two 50m-long tubular trusses spanning between three steel columns. These trusses are given extra support from twinned tie rods which tie up to the central column about 20m above roof level. The four aerofoils are hung beneath these trusses and are tied, front and rear, down to the structure below for stability.
Because of the forward-sloping roof and the architect's requirement for no visible drainage, we introduced an innovative vacuum drainage system. The system was introduced solely to drain the roof but quickly became the main grey and foul water drainage to the stand as we realised its full potential, allowing us to route services more freely out of view.
Prefabricating elements proved very successful. Phase II was structurally complete in 15 weeks, yet it comprised 108 precast slabs (~3.5 x 7m x 20 tonne average) interlinked with 138 precast terrace units, 27 steel raking beam frames, 90 tie rods and the spine truss itself.
John McKenna, Ove Arup & Partners