3.3.2 THE COOPERATION AND CONFLICTS IN
DESIGNING REINFORCED CONCRETE FRAME
The main building of the Tuberculosis Sanatorium of Southwest Finland was built on
a reinforced concrete frame in situ. The building report written by the architect, which
exhibited the input of the structural engineer, gave a thorough picture of the execution
of the concrete structures in the main building. Aalto considered the dimensioning of
the column system a demanding task.^682
The entrance lobby columns were cast in three-millimetre iron plate formworks
so that the formwork stayed in place as the surface of the finished column. Aalto and
Henriksson had used similar formwork in the asymmetrical columns of Turun Sanomat
newspaper printing hall. The exposed surfaces of the columns on the external wall or
the internal columns flanking the patient rooms were insulated with expanded cork.
The cork was cast onto the column surface.^683
All floors were made of reinforced concrete as well as the topmost beams support-
ing the roof. Apart from a few exceptions, such as the boiler room and workshops, all
roof structures had double-slabs with the topmost slab cast last. Tapered beams were
widely used in the building, with a thicker depth in the middle, where the compression
stress was at its highest.^684 The intermediate floors were built in three stages: first the
lower slab and beams were cast, followed by the laying of heating, water and sewer
pipework and electrical wiring, and finally the upper leaf was cast on a bed of filling.
With the upper leaf not resting directly on the beams, step sound insulating structure
was achieved. The filling used in the intermediate floors was fine-grade coke cinder
and the structural height was 45 centimetres.^685 The beam and slab floor system with a
floating upper leaf was a typical structural solution used in sanatoria in Finland in the
1930s. A similar structure was used in the City of Helsinki Tuberculosis Sanatorium
and Tarinaharju Sanatorium, both designed by Eino Forsman.^686 The large and techno-
logically advanced City of Helsinki Tuberculosis Sanatorium was held as a forerunner
and model for other sanatoria built in the 1930s, including Paimio Sanatorium.^687
Part of the beam system at Paimio Sanatorium served to carry air exhaust ducts,
and at these points the walls of the ducts were made of concrete slabs.^688 The upper
slab of the service building and the radiology department in B wing were designed to
withstand the weight of machinery.^689
682 Aalto [1930]a, p. 8.
683 Ibidem, p. 8.
684 Emil Henriksson’s structural drawings show that tapered beams were used in the wings. PSA; See also Neuvonen
et. al 2002, pp. 100–101.
685 Aalto [1930]a, p. 9.
686 Heikinheimo et al., Ark-byroo architects 2014, p. 48.
687 Laurila and Tandefeld 1968, pp. 607–662, particularly p. 660.
688 Aalto [1930]a, p. 9.
689 Ibidem, p. 9.