ALASTAIR BIGGART | INTERVIEW


f your grandfather was involved in building the Forth Railway Bridge, and your father built bridges and tunnels, odds are that you yourself will end up


as some sort of engineer. “All I remember is that from a pretty


young age, around ten, I thought I was going to be an engineer” says Alastair Biggart. “It was a fairly ill-formed thought at that time but I had no doubt about it, and when I left school I went straight to Loughborough University to do an engineering degree. “I was born in Glasgow, because I am


a Scot, but I was brought up in London because that’s where the family firm was.” The family firm was a civil engineering company by the name of Mitchell Brothers. “My father and his cousin owned it – the cousin was a Mitchell, which accounts for the name. I remember my father taking me down a tunnel he was building, I think it was a Post Office one, when I was quite young. So, yes, it’s really in the blood.” Hardly surprising then that after university


and a civil engineering degree, graduating in 1956 - and the then-obligatory two years of National Service, which he spent in the RAF and during which he learned to fly Vampire jets – he became an engineer, though not initially in the family concern. “I spent six years as an assistant engineer,


with four civil engineering contractors – Sir Robert McAlpine, Balfour Beatty, John Howard and Edmund Nuttall,” he says. “That gave me good and varied experience: there was tunnelling, there was road construction in the Scottish Highlands; I worked on the Greenock Dry Dock and on reinforced concrete and steel design. With Sir Robert McAlpine I worked on a Post Office tunnel under the Barbican in London. This was in


the days when most tunnels were lined in cast iron segments. I had the good fortune to work under Jim Buchanan as Agent. He remained in charge of McAlpine’s tunnelling for the remainder of his career and made a very large contribution to the UK tunnelling scene.” And then in 1964 Mitchell Brothers saw his


services. “I worked for them as sub-agent on the


Victoria Line in London.” That was in 1965, and much of the digging was by FL22 Clay Spades. “Then I moved to Head Office with my father, who taught me the art of tendering, and soon after I was appointed a director of the firm – a clear case of nepotism! I supervised a number of small tunnel projects and then I was back on the Victoria Line again, this time on the Vauxhall Extension.” “The Victoria Line, 1965 to 1975, saw huge


changes in tunnelling techniques. For one thing it rejected cast iron linings in favour of concrete. Many different designs were tried out. The consultants were Mott Hay and Anderson – they are now Mott MacDonald, of course – and Sir William Halcrow and Partners, who have been taken over long ago by an American group. Each of them designed different experimental types of concrete rings. Halcrows produced some very thin ones. Motts had a design where the segments were unbolted. At each side at axis level you put in a jack and expanded the whole ring, and then you put in concrete wedges to keep it all in place. It was very successful, though the system died out.” And, in place of the clay spades that had


dug the bulk of the original Victoria Line the extension saw experiments with the use of cohesive ground tunnel boring machines (TBMs).


“There were two, in fact. One was the


Kinnear Moodie Drum Digger, and the other the McAlpine Centre Shaft Digger. This was a UK first. The invention of the Slurry tunnelling machine and the Earth Pressure Balance (EPB) machine came later. “In 1970, I left Mitchell Brothers and


rejoined Edmund Nuttall. I was put in charge of estimating and was appointed a director of the company – no nepotism this time, so I suppose I must have earned it. And there I had a career-changing opportunity: I was put in charge of the New Cross Bentonite Tunnelling Machine experimental project. This was sponsored by the National Research and Development Corporation (NRDC). It was based on John Bartlett’s patent of 1964 for the Bentonite Tunnelling Machine, the precursor to the modern slurry machine. “As well as looking after estimating I


was director in charge of a number of tunnelling projects and finished my time with Nuttalls as Managing Director of Robert L Priestley, a subsidiary, which designed and manufactured TBMs. One of its machines was used on the 1972 Channel Tunnel Project, which was scrapped by the government. Priestley was closed down due to lack of business, in 1982. It wasn’t until 1985 that the Treaty of Canterbury was signed with the French and the Project then really got going. The rail link was fully completed and came into public service in 1994.” He joined Lilley Construction. “My main


responsibility was tendering for overseas tunnelling projects. The next year we won a $190 million contract (£648 million in today’s money) in Cairo for new sewers. I selected the tunnelling equipment for this project – we had three slurry tunnelling


Above left: Alastair Biggart’s period of National Service in the RAF saw him learn to fly Vampire jets... Above right: ...and then, after, his early experience as a civil engineer saw works at Greenock dry dock


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