Modern masterpieces
Professor David Nethercot explains why structural engineers are the Master Craftsmen of the 21st Century
In today’s world, we are surrounded by structures. They underpin our way of life and form an integral part of our existence. But who provides our schools and hospitals, bridges and tunnels, stations and airports, sports stadia and concert halls? The answer is, of course, that it is a team effort, combining the skills and ambitions of many professionals, from the client, through the designers and constructors (including those who maintain and refurbish), to the operators. But who ensures that all these Structures actually ‘stand up’? It’s the structural engineers.
Major facilities that have recently featured in the news such as the Olympic Stadium, which has housed the World Athletics championships, the Queensferry Crossing in Edinburgh and the remodelled and new stations on the still under construction Crossrail all rely on the work of their structural engineers for successful completion and operation. Some structures such as the London Eye or the arch supporting the roof of Wembley Stadium make the structural features very visible; for others such as the Shard or the Guggenheim Museum in Bilbao the structural framing is hidden, allowing the visitors to focus on the contents and activities within the buildings.
Taking just one of these examples: what role did structural engineering play in the creation of the Wembley arch? Of course, there is a vital architectural input considering impact and functionality so as to provide a stadium that deliversto spectators the necessary ‘experience’. But, having decided that suspending the roof from a very visible and potentially spectacular arch should be part of the solution, how are the form and proportions of that arch decided upon? What loading does it have to resist, by how much can it be allowed to deform and how will this performance be ensured? What about crowd dynamics and ensuring its integrity whilst it is actually being built? All of these questions and more depend upon the appropriate structural engineering understanding and knowledge to provide a safe, cost effective and functional outcome.
Challenging projects require high quality structural engineering input; an area in which British companies enjoy a very strong reputation worldwide. How better to appreciate this than to peruse this year’s list of projects shortlisted for the Institution of Structural Engineers’ Structural Awards 2017. Now in its 50th year and attracting entries from Chile to China, from Antigua to Australia and from South Africa to Sweden, this event showcases the ingenuity, versatility and flair of structural engineers in delivering stunningsolutions for projects costing a few tens of thousands of pounds to those involving ten figure sums. What distinguishes the shortlisted and the eventual winning entries is the excellence of the structural engineering. This is sometimes demonstrated by mastery of a comprehensive set of challenges and the identification of a solution that meets each of these with an equally comprehensive integrated solution. Other times it’s by devising one ingenious feature that permits other aspects to cluster around this. Some examples from this year’s list provide a feel for just what is possible:
‘The Crow’s Nest’ is a restored holiday home in Dorset’s dramatic Jurassic Coast. But its scenic location comes with the problem that the site is an active land slip area, which had resulted in significant damage to the building from repeated ground movements. By devising an ingenious foundation scheme that could accommodate the anticipated levels of movement the structural engineers were able to provide a safe, tolerant and wonderful home. Moving to the other side of the world, the Makatote railway viaduct in the south of Ne Zealand is a historic structure dating back to the early 20th century. Initial assessments had revealed that, over the years, it had deteriorated and that this, coupled with the need to carry heavier and more frequent trains, meant that a new bridge was needed. However, through careful investigation of its exact state, leading to a thorough understanding of the capacity of each of its component parts and the sensitive strengthening of those regarded as inadequate, the bridge was upgraded whilst remaining open.
Amesbury School in Hindhead needed a new building to house its expanding Visual Arts Activities. Rather than opting for asimple prefabricated solution the School worked with the structural engineers to produce a striking timber framed structure that maximises natural light, provides a stimulating environment for the pupils and even accommodates an historic tree. Moreover, the project deliberately utilised local materials and suppliers, thereby safeguarding the environment and supporting the local economy.
In reflection, the above suggeststhat structural engineers have a strong claim to be the ‘master craftsmen’ of the Construction Industry. At its most basic their contribution ensures the safety of the structures with which they are concerned. But that is to consider only their essential function. Good structural engineering can, as has been illustrated above, convert a seemingly flawed situation into a valuable asset, change what could well have been a utilitarian solution into the preservationand improvement of a national treasure or ensure that a dull shed becomes an attractive building constructed in a way that respects the local community. All three schemes benefitted from the engagement of structural engineers with the expertise, flair and tenacity to produce the exceptional rather than the mundane solution.
Interestingly, in the European Guild system of the Middle Ages becoming a master craftsman required acceptance by one’s peers through a system of apprenticeship and the presentation of a masterpiece. Whilst we do not have quite the same arrangement for becoming a professionally qualified structural engineer, the principles are the same. So, in terms of the competence we possess, the way in which that is assessed and our responsibilities for the integrity of construction projects we have a strong claim to be the Master Craftsmen of this century.
Professor D A Nethercot OBE, FREng, FTSE, NAE is Emeritus Professor of Civil Engineering Imperial College London, UK. The Department ofCivil and Environmental Engineering at Imperial College London is regularly ranked as one of the world’s leaders in its field. With some 50 academic staff, 400 undergraduate students and 450 postgraduate students it is a major supplier of both highly educated manpower and new technical knowledge to the construction industry.
For more information, please see www.imperial.ac.uk