Excellent structures are an important part of our quality of life, they contribute to what in German is called "Baukultur", the culture of building. It is the responsibility of structural and civil engineers to dope buildings and our built technical infrastructure - bridges, towers, roofs - with high-quality structures to make a positive contribution to the culture of building and to satisfy ourselves. Among engineers this is spoken of as structural elegance, but is elegance a vital ingredient when creating high-quality structures?
There is not much that has been written about elegant structures, which could be the result of elegance not being mentioned as an issue when engineering structures. As soon as we identify elegance as an element of beauty we have reached the field of aesthetics, i.e. how matters move our senses, and the aesthetic quality of our structures is clearly of importance.
The intent of this paper is the, admittedly personal, definition of structural elegance, to show that it is a key ingredient for creating high-quality structures and what we as engineers must do to achieve these structures.
What are the ideals of good structures? When we study milestone structures we find that engineers and architects try to follow similar principles.
The Roman architect Vitruvius, perhaps the most cited writer in this context and certainly one of the first ones to write about structural design, coined the terms firmitas, utilitas and venustas as the basics of good structures as early as 25 B.C. First, the structures must stand up and remain in good condition (firmitas), secondly they must be useful for their purpose (utilitas) and finally they should be aesthetically pleasing (venustas).
Volkwin Marg, a contemporary German architect, defines the culture of building as the synthesis of two sides of a coin - technology and art - which, he says, can only be achieved when architects and engineers creatively work together. He reaches back to the Platonic trias: truth, goodness and beauty. Intellectual truthfulness where structure and form coincide, goodness in the sense of our buildings´ contribution to society and its individuals and finally beauty which is allowed to shine through when goodness and truthfulness are successfully merged.
In the context of this paper lightweight structures seem especially interesting and the German engineer Jörg Schlaich identifies them as ecological, social and cultural. They are ecological in the true sense of sustainability as they minimise the use of our resources and as they are easy to assemble and to recycle. They are social because they require the employment of a proportionally high number of skilled designers and well-trained workers. Finally, they "can make a significant contribution to enrich the architectural spectrum". Refined lightness triggers positive emotions and we admire the beauty of lightweight structures because we understand them, as nothing is hiding the flow of the forces. They are an "integral part of the culture of building".
David Billington, an American engineer, in the 1980s coined the term structural art, the art of structural engineering parallel to architectural art. He defines the ideals of structural art as efficiency, economy and elegance. He notes that engineers are no scientists as they rather invent than discover. They invent good bridges, towers, long-span roofs and high-rise buildings by successfully merging minimized use of material at minimal cost with conscious aesthetic decisions.
The Japanese architect, Tadao Ando does not list a trias when he writes about elegance and the aesthetics of simplicity as part of the Japanese way of life. According to Ando, "Wabi Sabi", modest and weathered, inspires elegance in architecture by minimising again and again until only utility and beauty are left. The Wabi Sabi house is the result of "modest living, learning, being pleased with a life that does without anything superfluous and living the moment".
Looking only at the few writers cited above it is interesting to note that only one of them, the engineer Billington, uses the term elegance. What is furthermore surprising is that sustainability is not explicitly mentioned. However, as soon as we look closer we detect that sustainable building, i.e. resource efficiency and environmental responsibility throughout the life-cycle of a structure, is an inherent feature of the principles above.
Engineers, architects and sculptors all create three-dimensional structures and, therefore, have to follow the above principles alike. The difference between them is the importance they give to each of the principles. Of course, the sculptor too must make sure his work stands up but no code requires a 100-years design life for his work. He can concentrate on moving the senses. The prototype of the architect´s building is the one-family house and there firmitas is usually easy to achieve. Social issues become more important. Volkwin Marg calls architecture a "dance in chains" because so many boundary conditions make "dancing" much more difficult than it is for the artist, the sculptor who can freely choose which way to go. For us engineers this is even more so the case. Numerous restrictions by codes and standards provide us with the excuse to give up dancing all together, to only follow part of the principles that define a good structure. We seem to be so absorbed by dealing with the chains, by arranging them, by making them bearable and by not trying to break them that we forget that, indeed, dancing is still possible. In fact, it is necessary, a responsibility. If we learn how to dance in chains, there is a good chance that elegance will appear. If we holistically approach our work, we will be rewarded with good structure that contribute to the culture of building.
The principles of good structures, that are presented above, all include elements of beauty and elegance and clearly show that we may not work without bearing them in mind. There is evidence. In all fields of engineering and architecture elegant structures have appeared and we see and feel that elegance does not appear alone but rather in a package with the other principals.
Four examples of elegant structures, a house, a roof, a bridge and a tower are shown in fig. 4, 5 and 6 below.
Like many other terms, "elegance" has changed its meaning over time. The word stems from the Latin verb eligere = select, which later appeared in the French noun élégance. We use it today when we want to describe something of selected beauty. It is more than beauty-only. Elegance is often related to:
Most importantly, elegance appears effortless. When we consider that something is beautiful in its simplicity without realizing all the work that was needed to achieve it, we find it elegant. Sometimes elegance is mistaken for superficial luxury. In this case the word loses its allure and consumerism has had its day.
Following the above definitions, we can ask ourselves: are both chairs shown below beautiful? Are both elegant? The lounge chair by Ray and Charles Eames is most beautiful (and very comfortable) but many would agree that Barcelona Chair by Ludwig Mies van der Rohe is more elegant.
When our structures are of holistic quality, then they can also become elegant. Which way we follow to achieve this, how we call the ideals and principles we want to follow does not really matter. We can follow any of the above ways. We do not have to become dogmatic in our efforts to design good structures.
What is important, however, is that in addition to the principles we understand the design of a structure as a conscious act, an act of conceiving the solution by carefully considering the local context, the boundary conditions to our design that can be of topographical-physical, technical-fabricational or political-cultural nature.
It is interesting to note, that often good structures show a readable flow of forces, perhaps because they are easy to understand and because we like what we understand. Elegant structures are often light-weight structures.
It is important to create public awareness for good design of structures there is still a lot that should be done in this field:
Conceptual and Structural design of structures is a creative act based on sound theoretical knowledge and the principles described above. If the result appears to be achieved effortlessly we have created an elegant structure. This is not an easy task and it requires experience. Many of the great engineers achieved their greatest successes only when they were between forty and sixty years old. There is still hope for many of us.
In addition to "firmitas" and "utilitas" structures must be beautiful to become holistically good, to become a "Gesamtkunstwerk". Good structures stimulate good life, they can add to our quality of life. Elegance appears when the challenging task of fusing the principles of good structures seems to be achieved without much effort. If the response to a challenge appears effortless, elegance has appeared. Good life is not easy, it is a challenge but we want to live it elegantly. The claim is that elegant structures stimulate elegant life.
This article was published by George-Bähr-Forum of TU Dresden
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