Beam Architecture Continued
Here are some town views showing modern buildings, often close to older ones.
In a country where sunlight is not strong, and many days are dull, a large area of grey untextured concrete is a good recipe for drab surroundings. The response of materials to wear and tear and to weathering is very important in the design of buildings. Some materials and coatings can look very tatty quite quickly. The effects of water running down and depositing impurities can, over a long period, detract from appearance. Metal, concrete and plastic surfaces are among the materials which can degrade unattractively. See the page about appearance for more discussion.
How much of this is subjective? Tourists are often quite happy to see very old buildings, heavily weathered, not very clean, with bits missing, and showing clear deviations from horizontal and vertical, some original - others the result of time. Will people one day call steel and concrete buildings quaint? Will the buildings last that long?
This building includes both trabeate and arched designs. The frontage deviates very slightly from straight. What could be the reason for this? The yellowish "pillars" carry no load at all: they are merely affixed to the front of the building. A frontal view reveals that they are quite strongly bulged, as if to suggest the great load they are supposedly carrying. As the real load-bearing pillars behind (which may themselves conceal steel girders) are perfectly straight, the result is incongruous. Perhaps they are intended as a joke.
Some people like "functional" things. One function of functional things is to please people who like functional things. There's nothing wrong with functionalism - who wants a teapot that looks elegant, but dribbles? These caryatids are functionalist - they don't need arms - and they don't have arms. That must have saved a bob or two.
Look at the pictures below. Are the profiles of the pillars straight, or slightly curved? Does it make a difference? What about the ratio of width to height? The appearance of a structure can be affected by quite small details, or even by their absence. People often modernize their houses by replacing doors and windows. If the changes are too great, the balance of the design can be changed.
Here are some buildings which have various proportions of rectangular and arched windows. In earlier times, these were fashionable dwellings in a spa town: now they are either offices or apartments.
This picture shows a mixture of buildings of different ages. In the foreground is a late 20th century office block, far taller than any other building in the town. Behind it is a block of apartments built at the start of the 21st century. At the top left is a school in a mock gothic style, including, at the extreme top left, a huge sports pavilion. Many other buildings in the picture are elegant houses.
What do you do if you have to build something new in an area with an established character? Clifton, near Bristol, has numerous elegant streets, like the examples already given. The builders of the Roman Catholic cathedral chose to construct a building in a modern idiom, as did those in Liverpool. The Church of England cathedral in Liverpool is a complete contrast - a massive structure in Gothic style.
Just because they look like arches, it doesn't mean that they are. These are not connected to the buildings on either side, so they must be beams. Waterloo Bridge in London has curved spans, but they are haunched beams, not arches, giving good headroom while transmitting the forces through the bridge.
Administrative building and lecture theatre at CERN, Meyrin. A few departures from a strict rectangular construction make the building more interesting. White concrete, and strong sunlight, add the final touches.
Buildings at Meyrin, north west of Geneva, are smaller than those at Les Avanchets. Meyrin is a pleasant cité satellite, with a good shopping centre, good schools, and cultural facilities. Balconies allow people to install sun-shades, flowering plants, and other things that add colour and variety. Alongside these buildings are those of the older village.
Here is a picture showing Birmingham airport. If you are bored at an airport you can wander around and look at the architecture and structures. At JFK you can even look at the famous TWA terminal by Saarinen, Ammann and Whitney. At the right of this photograph are some of the huge boxes which comprise the National Exhibition Centre - trabeated "architecture" taken to its limit of simplicity. The roofs of such buildings are often supported by light trusses or space frames. At the far right you can see the red tension bars holding up the roof of the National Indoor Arena.
Not all beams are horizontal. These are glass houses in Kew Gardens. At their lower ends there must be provision to contain the thrust they generate. Beams like this could butt against thrust blocks with strong foundations, or they could be tied by rods under the ground. These beams are in compression, unlike horizontal ones. You could even think of these structures as primitive arches.
Other deviations from the right angle have included octagonal church towers, such as that at Hornby in Lancashire, which is unusual in that the upper section of the tower is rotated by 22.5° with respect to the lower part. Many medieval castles had circular towers, probably for defensive reasons.
To see how styles and techniques change with time, it can be useful to look at a series of buildings intended for a single purpose. Here are some English schools in styles of different periods, in order of construction -
Some of these pictures illustrate the dominance of the rectangle in the middle decades of the 20th century. Some of the pictures at the top of the page about arches in architecture show that in the last two decades of the 20th century there was a return to the use of circles and arches, and more imaginative design in general, exemplified by the last picture in the set above. In Britain, during the rectangular period, many school buildings took the form of prefabricated boxes, similar to those used for temporary buildings in building sites and industrial areas. Large numbers of children are still taught in these buildings.
Older Japanese styles, based on styles imported from China, used wood, making extensive use of beams, and large eaves based on cantilevered brackets. The rectangles were relieved by the slight curvature of the roof lines. Rooms, too, were based on endless, yet never boring, permutations of rectangles, built around the standard tatami, the rectangular mat with proportions of 2 : 1. These pictures show the Todaiji Temple, in Nara, the Heian Shrine in Kyoto, the Golden Pavilion in the Kinkakuji Temple in Kyoto, and a temple in Kamakura. The Tojaidi is the largest wooden building in the world.
An old mathematical problem concerns the maximum amount by which a pile of bricks can overhang before falling over. It turns out that the critical overlap of the Nth brick from the top is 1/Nth of the length of a brick. The proof neglects the imperfect rigidity of the bricks and the foundation. The shape is reminiscent of some species of snake when threatening to strike.
Although this is an impractical object, a set of diving boards at Coate Water, south of Swindon, is supported by a concrete tower which has a shape which looks a little like a smoothed version of this pile, although it has a subsidiary support at the back.
This pile of bricks violates the rule of the middle third, which states that the centre of gravity should lie over the middle third in both dimensions, that is, it must lie in the middle ninth of the area. Only then can we be sure that tension will not develop anywhere. In masonry, the rule should be followed from top to bottom. If there are transverse forces, as in a buttress or a retaining wall, it is the funicular which must lie within the middle third.
Under this rule, the overhang must be reduced, or the length of the blocks must be increased. What is the new formula for piling up the bricks? Is the trick even possible?
Not a Building
This is not a bridge or a dam, and it is not a building. What is it? It is one of the exhibits in the Yorkshire Sculpture Park. So what are we to look for? We could wonder about the soil and the foundations, since it shows no sign of relative movement. We might also wonder whether it is hollow: the objects that are apparently blocks might even be thin slabs fixed to a frame. We could even ask whether the work is aligned with a standard compass bearing.
This sculpture, not far from the previous example, illustrates the tendency of art to produce asymmetry: the first example was atypical in this respect. But asymmetry does not mean lack of form - the positions and shapes of the forms were chosen by the artist to produce whatever effect he desired.
Half Timbered Buildings
The half timbered building has a wooden frame, filled in with brick or some other material. This construction has the advantage that should any movement occur, the effects are localised within the frames, and cracks cannot spread. The effect of subsidence is far less serious than it would be in a building made entirely of bricks. One of the examples shown below has sunk very visibly. Another benefit of the infill is that it tends to rigidise the frames, though in fact many buildings include a few triangles.
Steel framed buildings are sometimes provided with a degree of triangulation to increase resistance to distortion. This arrangement is one of three that are present at each end of a long building. Why do we not need triangles throughout the building?
Architecture of the world - editor Henri Stierlin
publisher Benedikt - Taschen - about fourteen paperback books.
Developments in Structural Form R J Mainstone Allen Lane / Penguin
ISBN 0 14 00 6503 2 paperback 0 71 39 0333 3 hardback
The Guinness Book of Structures John H Stephens Guinness Superlatives Ltd
ISBN 0 900424 28 1 - much more than a list of data.
Structures: Or why things don't fall down J E Gordon
The New Science of Strong Materials: or why you don't fall through the floor J E Gordon
Building Structures Malcolm Millais E and FN Spon (Chapman and Hall) ISBN 0 419 21970 6
Fundamental Structural Analysis W J Spencer Macmillan Education
ISBN 0 333 43467 6
The Builders National Geographic Society ISBN 0-87044-836-6 1992
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