Ambiguous Rationality: The Structural Design of Alvar Aalto

Unlike "humanizing", "expressive forms", and "phenomenological significance of materials", Aalto's structural conception has been seldom recognized as masterly touches and even misunderstood by some theorists as "a-tectonic" and "irrational." Since initiating practice, he had developed a "surface + frame" composite as a structural solution. Then a "thick partition" formed with ambient spaces, became a basis to fully explore in spatial, lighting, and signifying dimensions, breaking a new path long before the "skin + bone" prototype of modern architecture received sublation from the younger generation.

This paper chooses three built churches throughout Aalto's career for a serial case study and reveals, through analyses from drawings to actual construction, how the composite system acts as a reasonable stress system and construction basis, participating in controlling the force system and force flows, how the "thick partition" mediates the spatial flows and directs the light-shadow interplay, and how such webs of significance have transcended the high modern architecture.