This paper aims to illustrate the framework of analogical thoughts on large span buildings by contemporary Japanese architects. In the design of large span buildings, architect sometimes get the inspiration by comparing the building to other thing. This analogical thought is one of the way of architects' conception approach of design, and it can be read from analogical expressions represented on the design theories of large span buildings.
Firstly, we extracted the reference object, to which is compared large span building in analogical expression. They were classified into two categories showed in Table1 (Natural object, Artificial object). We also examined what kinds of aspect were refered from these objects, they were classified into two categories showed in Fig. 2 (Visual aspect, Semantic aspect). Visual aspect is focusing on their visual character, and it was divided further; the shape of the object and the scene with the object. Semantic aspect is focusing on the impression of the object. We found that Visual aspect had larger numbers than the other,
Secondly, architects' intention of analogical expression was extracted from the articles and analyzed by the “KJ - method” (originated by KAWAKITA Jiro). We found four categories of architects’ intention; [Response to building surroundings], [Represent regionality], [Clarify the mechanism of the building], [Create the spatial character](Fig. 3). [Response to building surroundings] and [Represent regionality] are about the relationship between building and environment. [Clarify the mechanism of the building] and [Create the spatial character] are about the building itself. Additionally, we considered the area of the building where these intentions direct to; inside, outside, both inside and outside, then we found [Clarify the mechanism of the building] was more related to various areas.
Finally, the relationship between the reference aspect and the intention of analogical expression were examined totally (Fig. 4). There were strong relations between [Response to building surroundings] and Visual aspect with the shape of the object, and [Represent regionality] and [Clarify the mechanism of the building] had similar tendency. Only [Response to building surroundings] was also related to Visual aspect with the scene with the object. [Create the spatial character] had unique tendency, it was related to Semantic aspect.
As a result, we clearly showed the analogical thoughts by architects as the following. When they represent regionality, they design the building sympathized with the regional civilizations, using the analogy with the shape of the building rooted in the area, and when they respond to the surroundings of the building, they harmonize the building shape with the existing landscape, using the analogy with the shape of the natural object, while they represent the new landscape participated the building, using the analogy with the scene with the artificial object. In addition, when they thought about the building itself, they clarify the mechanism of the building, using the analogy of the shape of a living thing or the artificial object, while they create the spatial character of the building, using the analogy with the impression of the artificial object.
