Engineering in Time

Engineering in Time
Martha Dillon discusses why civil engineers should care about the past

In architecture, an understanding of ancient buildings and a working knowledge of their history is taken as a given. Norman Foster, master of the then-futuristic glass skyscraper, once commented that “as an architect you design for the present, with an awareness of the past, for a future which is essentially unknown”. ­This typifies the attitude of most designers: old and new are important, and each informs the other. So why is this opinion, which is so fundamental to most areas of modern design, absent from modern engineering and construction?

In 1916, the infamous Henry Ford announced that he believed “history is more or less bunk”, and went on to create one of the largest car manufacturing companies in the world. ­This is a classic view in an industry that exists almost completely without reference to history and context. Among engineers, a sense of the past can be seen as largely irrelevant to the progress of the future. Of course, it is an exaggeration to say that there is no discussion of historic engineering – the rather unusual name of the 19th century engineer extraordinaire Isambard Kingdom Brunel still carries a lot of weight today. And yet, the stereotype that engineers do the maths whilst architects deal with the context is uncomfortably strong. Engineering courses cover very little work before the industrial revolution, modern designs are rarely based on existing projects, and the inflexibility of construction codes constrains the lateral thinking that could draw on innovative solutions from the past. This attitude is a shame. It further divorces engineers from the vital creative processes involved in infrastructure and design projects.

Image: Martha Dillon

The detailed structural theories of today may be a better model for our skyscrapers than those used by Imhotep, designer of the Pyramid of Djoser at Saqqara and arguably the first civil engineer. Yet it is short-sighted to think that historic engineering solutions are inapplicable. The tallest building in the world, the Burj Khalifa in Dubai, has an innovative buttressed core that helps it achieve its height. Buttresses are structural ‘outstands’ that aid with the support of large structures, usually walls and towers. However, structural engineers have used them for centuries to achieve more stable shapes, from the flying buttresses of Notre Dame in Paris (1163) to the earthquake-resisting buttresses of Baroque Guatemalan churches (in the 1600s).

There are even examples of ancient civil engineering projects more successful than the works that have replaced them. In the first millennium BC, the one million residents of the city of Merv (in what is now Turkmenistan) were serviced by 700 square kilometres of cultivated land, in a staggering centralised irrigation system. Hourly readings were taken of canal levels, trees were planted to prevent stagnant water pooling, and engineers built networks of salt accumulators that prevented desalination. These structures were largely destroyed in the early 13th century Mongol invasion of the area, and replaced by engineers as part of the 19th century Russian annexation. Subsequent dam and canal systems have led to near-complete disappearance of the sea and loss of most surrounding agricultural land. We appear not to have learnt from this event: from the Great Salt Lake in Utah to Lake Titicaca in South America, lakes across the planet are drying up due to human activity, compounded by climate change. Reinventing the wheel for every new project is both inefficient and unimaginative, but most importantly, it is short-sighted.

Historic engineering traditions are also a rich source of inspiration for tapping into natural and traditional systems. The designers of the ‘Better Shelter’, a refugee shelter produced by the UNHCR, learnt a huge amount about dealing with unusual conditions from observing traditional methods of heating and cooling. They found that Ethiopian families would retain uncovered portions of ground in their shelters on which they would pour water. When this water evaporated, it had a cooling effect on the interior of the shelter that did not rely on shading or ventilation systems.

Similarly, biomimicry has been a historically influential field that is only recently being fully explored by modern designers. This is a discipline that “seeks sustainable solutions to human challenges by emulating nature’s time-tested patterns and strategies.” Engineers throughout history have used biomimicry to innovate in ways that remain applicable today. The original 18th century Marc Brunel tunnel boring designs were purportedly inspired by shipworms, bivalve molluscs which ‘drill’ into wood using two small shells at their heads. ­The Wright brothers famously looked to pigeons when trying to achieve powered flight at the beginning of the 20th century. If engineering is about solving physical problems, then the imagination to tap into a wide variety of processes and concepts is always important.

Clearly there is a lot to be learnt from the past to inspire the future, and there are lessons to be learnt from past mistakes. However, an understanding of the legacy of past designers and the comparative state of our own technologies is crucial if modern engineers are to be in control of their impact and visions for the future. After all, the status of a society is firmly rooted in its technology – just take the example of foundation piles. In 450 BC, Herodotus recounted that the marriage of a Paeonian man was traditionally followed by a ceremony where he drove three timber piles into a plot of land to provide the foundations of his new home. Since the tribe was largely polygamous, the settlements of those communities grew very large and complicated. Something as simple as foundations thus neatly illustrates a significant amount about the society.

We can learn from the past, be inspired by the past, and act more effectively if we understand the past

By contrast, the early mediaeval ‘dark ages’ are characterised by the lack of surviving design, piles or otherwise. ­These are the years 500-1000 AD, where many of the innovations and systems designed by the Romans (such as road networks, water supply lines and sewage systems) decayed, with a corresponding reduction in the quality of life. Nowadays, foundation piles are numerous, long, and densely packed to accommodate the increasingly tall buildings that make up our cities. The ground under cities is riddled with tunnels, while seabeds are home to networks of pipelines and cables. This is an enormous legacy to be responsible for. It is vital that engineers realise that history will judge their projects for so much more than just the technology behind them.

This idea of legacy is all the more important as we begin to appreciate importance of sustainability. Thinking about how our projects will physically last is essential. We are beginning to understand the longer-term consequences of using up the precious metals in the ground or diverting a waterway: it is negligent to avoid responsibility for the social impact and context of our work. ­This is powerfully demonstrated by the sharp change in global CO2 emissions following the 18th century industrial revolution. It is an indicator of the immense progress it heralded, but also an example of the drastic social and environmental consequences that can follow a technological change. We cannot develop sustainably without looking at how both our contemporaries and predecessors managed. If we are to start building in a way that is sustainable and thoughtful, we need to understand what went before us – whether to help avoid the mistakes of the past or simply to inform how projects may age.

Civil engineers thus have many incentives to appreciate the history of their predecessors. We can learn from the past, be inspired by the past, and act more effectively if we understand the past. Instead of treating design as a series of fresh equations, engineers can draw on a range of innovations and stories. We are responsible for implementing human ideas: that is so much bigger, and more complex than a mere mathematical problem.