Title: Louis I. Kahn and the Nature of Concrete

Author(s): R. McCarter

Publication: Concrete International

Volume: 31

Issue: 12

Appears on pages(s): 26-33

Keywords: folded plate, Vierendeel trusses, cycloidal shell, post-tensioning

DOI:

Date: 12/1/2009

Abstract:
After a discussion of Kahn’s ideas on the nature of concrete, the author shows how two of the architect’s greatest works, the Salk Institute and the Kimbell Art Museum, were linked by a single concrete structural conception. Kahn’s initial design for the Salk Institute comprised four, two-story buildings with post-tensioned folded plate concrete beams spanning 50 ft (15.2 m) to 100 ft long (30.5 m) precast concrete girders. At the top floor, natural light was to be introduced through a joint between the beams. After the program was changed so that the laboratories would be housed in two buildings, the structure was changed to comprise Vierendeel trusses spanning 60 ft (18.3 m). Kahn’s initial design for the Kimbell Art Museum was also a folded plate concrete structure that can be directly related to the "lost" folded plate structure for the Salk Institute. The design evolved to a series of cycloidal shells spanning 100 ft (30.5 m) to end diaphragms. The shells hold central skylights and an aluminum reflector system that bounces light off the curved concrete shells. Kahn used concrete as the finished surface of the shells, which serve as the light sources for the museum spaces.