French pioneer of experimental concrete construction, who, with his brothers, Louis (1819– ) and Stéphane (1820– ), took over the family's chemical works in Lyon in 1846. He patented a concrete with a clinker aggregate in 1854, and opened a new factory at St-Denis, itself built of pre-cast clinker-blocks, to manufacture it. In order to advertise his products he built (1853) a house (designed by Théodore Lachèz (fl. 1820–60) ) at St-Denis which was entirely of artificial stone. From that time he concentrated his energies to the study of concrete and artificial stone. One of his largest projects was the construction of the aqueduct of the Vanne (1867–74), nearly 140 km (87 miles) long, and with some arches as high as 40 metres, and he built the sea wall at Saint-Jean-de-Luz (1857–93). He provided the concrete elements for L. -C. Boileau's Church of Ste-Marguerite, Le Vésinet (Seine-et-Oise), of 1862–5, but Boileau complained of poor adhesion and water-penetration. His son, Edmond Coignet (1856–1915), was also an inventor, and with the architect Jacques Hermant, erected two of the first reinforced-concrete buildings: Le Magasin des Classes Laborieuses de-partment-store in the Rue St-Martin, and the Salle Gaveau concert-hall, Rue St-Honoré (1906–7), both in Paris. Edmond Coignet patented his system in 1892.
Cruickshank (ed.) (1996);Marrey (1989);Marrey (ed.) (2002);Jane Turner (1996)