Kahn System

In March 1906, Asa J. Biggs (†1913); a Massachusetts Institute of Technology-trained engineer and principal in the New Orleans firm Mackenzie, Goldstein & Biggs; wrote an article for Architectural Art and Its Allies heralding a new reinforced-concrete building technique, the Kahn system. Invented by Julius Kahn and patented 18 August 1903 (Patent No. 736,602), the system featured rolled bars with diagonal "wings" bent up at regular intervals to prevent shear cracks in horizontal beams (see diagram on envelope below). Kahn's Detroit-based Trussed Concrete Steel Company manufactured and marketed the reinforcement system, and its structural engineers supplied builders with their services.

Frank Lloyd Wright employed the Kahn system in his Imperial Hotel (1913-23) in Tokyo.(1)  In New Orleans, Bemis Brothers' Gulf Bag Company building (329 Julia Street) was erected on 660 Raymond concrete piles, and its beams and floor slabs employed the Kahn system (1905-06).  This facilitated the builder's desire to span a clear space of 44 feet that would allow heavy bales of burlap cloth to be loaded and unloaded.(2) Edmund Burke Mason was the engineer in charge of construction for Bemis Brothers Bag Company of Boston, and supervised the construction of the Julia Street facility, as well as that of Bemis plants in San Francisco and St. Louis.(3)

(1) Joseph M. Siry. "The Architecture of Earthquake Resistance: Julius Kahn's Truscan Company and Frank Lloyd Wright's Imperial Hotel" Journal of the Society of Architectural Historians 67:1 (March 2008): pp. 78-105.

(2) Asa J. Biggs. "A Re-Inforced Concrete Factory." Architectural Art and Its Allies (March 1906), pp. 13-14.

(3)John Smith Kendall. "Edmund Burke Mason." History of New Orleans, vol. 3. 1922. p. 946.

Images above: "Gulf Bag Company Building." Architectural Art and Its Allies (March 1906), p. 13; Trussed Concrete Steel Company envelope, 1909. "Louisiana Printing Co.," Martin Shepard Office Records, Southeastern Architectural Archive, Special Collections Division, Tulane University Libraries.