Innovation: Cast Iron Masonry Reinforcing, First Compression Tests on Building Materials
Location: Paris, France
By: Jean-Baptiste Rondelet
The Pantheon in Paris, France was originally dedicated to St. Genevieve, but through many changes in its history, it now serves as a mausoleum for many of France’s most distinguished citizens. The original architect was Jacques-Germain Soufflot, and he wished to bring two of the old world’s most beautiful architectural forms, Classical Roman and Gothic, together in one amalgamation of high art. The church was an ambitious project because Soufflot wished to create more open space than was customary in churches at the time. This was achieved by combining the strong arches of Roman architecture with the lofty, slender columns often seen in Gothic cathedrals [1,2]. To prove to his critics that the design was stable, Soufflot created and performed the first systematic compression tests and resulting calculations showing that the slender columns had an appropriate cross-sectional area to sustain centered loads. Unfortunately Soufflot died before he could see his project through, and so his apprentice, Rondelet, took over. Rondelet was responsible for the reinforcing metal used in the masonry units of the flat arches supporting the massive pediment, and he specified the placement of reinforcing metal rings in the domes to resist thrusting. These particular innovations were very new to the architectural scene, and Rondelet had to face critics claiming that his method was against many of the design standards and philosophies of the time. One thing is very clear from this building, it paved the way for the how structural analysis, materials testing, and metal reinforcing would be carried out in modern architectural engineering.