Development of the Vierendeel: calculation, aesthetics, welding, concrete

Abstract

The Vierendeel is a frame with rigid joints patented in 1896 by Belgian engineer ArthurVierendeel (1852-1940). His invention came about after he noticed that experiments and calculationmethods on iron and steel frameworks didn‟t agree, making his invention a response in the then discussionon secondary stresses. After designing a church tower and testing a full-scale bridge model during the 1897Brussels World Fair, many bridges „système Vierendeel‟ were erected the following decades in hishomeland, as well as a few dozens around the globe. At times the discussion on the Vierendeel got heatedin trade journals and amongst people, mainly due to a lack of „visual‟ safety and theoretical uncertaintiesconcerning calculation, safety factors and welding techniques. Nowadays the Vierendeel principle is stilltopical and many (structural) designers apply his formal ideas. This led to a broader meaning of the wordVierendeel varying from aesthetic to strictly structural.