The Man Who Tore The Tate In Two: Stuart Smith on making Doris Salcedo's Shibboleth a reality

When an artist drives a gully through the heart of the world’s most-visited art gallery it’s almost unthinkable that it’s the product of anything less than divine intervention. Though your gut tells you there’s a rational explanation for what you’re seeing, your inner fantasist doesn’t want to let go of the magic of the piece, the fantastical tear in the fabric of the gallery. In fact, the reality is much more interesting. “Somewhere out there is an engineer that made all of this happen,” said journalist Mark Miodownik speaking on BBC Radio 4 in late 2007. He was referring to Doris Salcedo’s Shibboleth, the work of dramatic sculptural presence that transformed the Tate Modern’s main atrium from a polished exhibition space into the scene of some ambiguous natural disaster. Slap bang in the middle of the Turbine Hall’s vast concrete floor was a crack of alarming proportions, splitting the floor right down the centre. The inexplicable crevice began at the gallery doors and trailed down into the body of the room, expanding as it progressed but, mysteriously, revealing nothing of the space beneath. The work was a massive critical success; as an allegory for the colonial foundations of Western society it had heavyweight conceptual punch and for the weekend art admirer it looked utterly spectacular. But the greatest success of Shibboleth was its ambiguity; nobody knew how the concrete chasm arrived there. Salcedo wasn’t for telling and neither were the people she’d enlisted to help. Five years later the memory of Shibboleth persists, albeit distorted by time and our own fallible perceptions. Some people remember being able to step into the crack completely (you couldn’t) others that it was possible to see through to the earth below (it wasn’t) and I remember the opening growing in size as the exhibition wore on (it definitely didn’t). By preserving the mystique of its genesis, Salcedo allowed her viewers to create a lasting personal mythology around Shibboleth that’s as complex and uncertain as the work of art itself, and that’s largely thanks to the complicity of Stuart Smith. “I love looking at these pictures,” he says, thumbing through the exhibition catalogue. “I’m still very proud of what we did.” Stuart has every right to be proud – as the mathematical brain behind some of the world’s most complex architectural structures he ought to have achieved rockstar status by now. But in an industry that produces few celebrities, it’s unsurprising to find he cuts a pretty unassuming figure in person. Stuart is a structural engineer at Arup, a global firm of consulting engineers famed for their work on structures like the Sydney Opera House, The Pompidou Centre, the Olympic Aquatics centres in both Beijing and London and the redevelopment of King’s Cross Station. He’s also the brains behind making Shibboleth a reality; his specialist understanding of concrete facilitated that ominous crack and allowed Salcedo to produce a bewildering spectacle without blowing the Tate’s budget or compromising the building’s structural integrity. Stuart’s involvement came about quite by coincidence. “The Tate had commissioned Doris to do this piece and she’d proposed the idea of putting a crack through the Turbine Hall. It had to open in October, but around February they were going nowhere – they couldn’t work out how to do it. The idea was to cut directly into the concrete which obviously wasn’t going to work. At the time I was working on the extension to the Tate and they asked me to help work out whether the piece could be done.” Making Salcedo’s idea a physical reality turned into a six-month personal project which saw the pair slaving through many successive nights (to allow for the time difference between London and Bogota) planning the piece out via Skype and plotting the best way to create the illusion they were looking for. “It was a very personal project, one-to-one with Doris.” Stuart tells me. “I went to Bogota to her studio to figure out how it would all work and how the pieces would be made and installed. The complexity of it was enormous because there were lots of ways of doing it that just wouldn’t have delivered what Doris wanted and wouldn’t have been as mystical. The most important thing was for the illusion to work straight away, and for that to happen all the details had to be exactly right.” Constructing that illusion required patience and skill, working in minute detail to ensure the fissure upheld its mysteries throughout its length. “When you looked into the crack, you couldn’t see the bottom, so nobody knew how deep it was, even in the main section.” For all its final polish, driving a chasm through the heart of the Tate was not without its difficulties. The main problem was the solid concrete slope that serves as the main entrance to the gallery. Cutting into it would have blown the entire budget, leaving no room to extend the piece through the rest of the space, but it was difficult to see how else the effect