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Department of Engineering

Concrete feedback

Concrete feedback

Mohammed Elshafie

Dr Mohammed Elshafie wants to give London not just a brain, but an entire nervous system.

In the future, a city will be like a vehicle – you get in and it can tell you the status of everything important you need to know.

Dr Mohammed Elshafie

"Here,” says Dr Mohammed Elshafie, opening an image on his computer screen that shows a network of snaking cables. “This is optical fibre, the nervous system of infrastructure. We can use it to communicate with different elements, like tunnels, bridges, roads and buildings. And here” – he points at a box onscreen that looks like an early computer, squat and square with winking lights – “the fibres talk to the brain. This is real, it’s not something in a lab in Cambridge that we’re trying to figure out.”

You’re unlikely ever to see any of Elshafie’s work. It happens deep underground, in construction trenches, pile pits, and behind the temporary hoardings of building sites. But if you’ve ever visited London you’ll certainly have walked across it, maybe have journeyed through it – and in future you may even live above it or empty your bathrooms into it. He and his colleagues (Elshafie frequently acknowledges the team at the Cambridge Centre for Smart Infrastructure and Construction – CSIC – and the leadership of CSIC head Professor Robert Mair, Professor Kenichi Soga and Professor Campbell Middleton) are fitting London one railway tunnel, deep basement and sewer at a time with these intelligent fibres.

Their hope is that one day it will become the world’s first “smart city”.

Achieving that transformation is less a matter of nuts and bolts than one of wires and boxes. The business of making infrastructure smarter is, conceptually at least, surprisingly simple. Traditionally, external sensors have been placed at specific points on, for example, a tunnel wall or construction pile core, that feed back readings from that particular spot. CSIC’s team instead thread their fibre optic cables throughout a structure’s interior, producing a complete picture of what is happening within it.

This is most useful in revealing the internal stresses that are vital when assessing a structure’s strength and safety. But potentially a great range of information can be captured: temperature, throughput and condition. And with that knowledge will come, in the future, the ability to manipulate these variables: to turn up heating or cooling, to regulate a bridge’s load or the flow of a tunnel’s contents – be it sewage, cars or commuters.

But if Elshafie – a Fellow of Robinson and Lecturer at the Laing O’Rourke Centre for Construction Engineering and Technology – is a visionary, he is an eminently practical one. Much of his time is spent out on construction sites or in tunnels deep underground, kitted out in a hard hat and protective gear, listening to endless health and safety briefings. That’s because in order to change our cities, we first have to effect major transformations in the way industry builds those cities.

“The construction industry has been doing things one way for years and years,” he says. “But we do not learn from the things we do, and these days there’s less money. We can’t keep doing things the same way.” When he says ‘we’ in observations like this, he is talking not about the CSIC team, but of building contractors, engineers and developers – an entire industry that he and his fellow scientists must win over to their new way of doing things. Elshafie, who spent some time working in industry between the various stages of his studies, is adept at putting himself in their shoes, but it’s no easy task. Despite project costs that can run into the high millions, profit margins are often as low as 2 to 3%. Consequently, risk aversion is high. The scientists must frequently demonstrate not only that their data enables the construction of safer, stronger infrastructure, but that it will also deliver efficiency savings – and won’t take up precious time on the job.

On one particular project – he won’t say which – the Cambridge team was asked to do a dummy-run demonstration of their technique. “We were timed with a stopwatch,” he recalls, with a smile. “And when we got the go-ahead to participate, we had to make sure we kept to within 20 seconds of that time.”

Their work isn’t just about helping contractors increase their margins; Elshafie says the benefits of smart infrastructure flow to everyone. Many of the super-scale projects CSIC works on draw on the public purse, such as the mighty Crossrail extensions across Greater London, Essex and Kent. Others – such as the new tunnels for the National Grid, or Thames Water’s Lee Tunnel – should deliver improved capacity and efficiency that will mean better and cheaper services for customers.

Still others bring environmental benefits, such as the City of London development at 6 Bevis Marks (neighbour to the famous Gherkin, 30 St Mary Axe) which won a major industry sustainability prize in 2013. The existing building on the site was demolished, but what remained uncertain – until Elshafie and the CSIC team came along – was whether its foundations could be re-used. Conventional wisdom said it could not, and Cementation Skanska faced the significant engineering challenge of extracting the old piles and creating new ones – a disruptive and costly process. But Elshafie and his colleagues, working together with Cementation Skanska, were able to establish that the existing foundations were both sound and strong. As a result, the new structure went up on top of the entire original ‘basement box’, shaving two months off the construction time and saving over 1000 tonnes of CO2 in the process.

But though Elshafie’s work is inseparable from the activities of the construction industry, and inspires innovation within it, he and his colleagues at CSIC remain, first and foremost, scholars and researchers. “It is the questions that drive us,” he says. Consequently plans are in hand for a spin-off commercial enterprise, in which trained experts will deploy CSIC’s technologies in more routine projects, while the research team continues to push boundaries in cutting-edge construction works.

Elshafie’s passion for engineering cities began early. He was born in Omdurman, Sudan, one of three districts comprising Khartoum State, which is partitioned by the confluence of the White Nile and the Blue Nile. Those districts were, during Elshafie’s childhood, linked by only three bridges, over one or two of which his father drove during every day’s school run. “Every time we crossed one of these bridges,” he recalls, “I would marvel at the beauty of their massive structures, and also the vital role they played in keeping the whole country alive.

That early wonder at the bridges, and an awareness of the significant challenges posed by the annual flooding of the twinned Nile, led Elshafie to study Civil Engineering, first at Khartoum University, where he graduated top of his year, and then – thanks to the award of an Overseas Research Student-ship, Commonwealth Trust Scholarship and a Gates Scholarship – in Cambridge, where he took his PhD and has stayed ever since. The experience of living in Cambridge is, in some ways, surprisingly like Khartoum, he says. “There, everybody knows everybody; I just have to stop anyone on the street and within a few minutes we’ll find a common friend or distant family member. And here, thanks to Cambridge’s tight academic community, it’s not unusual to find connections in the same way when meeting people.”

There are surprising similarities, too, in the civil engineering challenges both cities face. Where Khartoum had congested bridges and river flooding, Cambridge must cope with congested streets and storm flooding. “Underground facilities like tunnelling,” says Elshafie, “could offer an excellent solution for dealing with both in Cambridge.” (Indeed, Professor Mair sparked debate last year when he proposed tunnelling bus and light-rail routes beneath Cambridge’s centre.)

“Cities everywhere are becoming more crowded,” Elshafie explains. “You need more infrastructure for them and it will be progressively more complex. And it’s not only complexity at the moment of construction; it’ll reach into the future as that infrastructure ages. Another generation will be faced with questions about do they repair something, replace it, or rebuild it.”

In October 2013, the British Government launched the Smart Cities Forum to ensure that UK cities and companies are at the forefront of what the Department for Business, Innovation and Skills predicts will be a market worth £240bn globally by 2020. Elshafie, meanwhile, is convening the world’s first academic conference on the use of fibre optics sensing in civil infrastructure, to be held at Robinson this summer, and he hopes that scholars from as far afield as Japan, China, and Canada will attend.

“We think we’re on the top of our game,” he says. “But now we need to share that knowledge. My hope is that soon it will be hard to have projects without this sort of technology. In the future, a city will be like a vehicle – you get in and it can tell you the status of everything important you need to know.”

CV
2002
BSc Hons, Civil Engineering, University of Khartoum

2003
Structural engineer
at Komatsu Engineering

2004
UK Government Overseas Research Studentship  Award and Gates Cambridge Scholarship

2008
PhD, Geotechnical Engineering; Teaching Fellow, Robinson College

2009
Geotechnical engineer, Geotechnical Consulting Group

2009-11
Research Associate, Engineering Department

2011
Laing O’Rourke
Lecturer in Construction
Engineering

 

Words Victoria James
http://www.alumni.cam.ac.uk/sites/www.alumni.cam.ac.uk/files/documents/CAM71.pdf