Static Force — Charles Augustin Coulomb
Charles Augustin Coulomb pioneered the development of structural analysis to identify conditions under which a structure will fail. Coulomb began his career in 1764 as a military engineer assigned to build a fort on island of Martinique. Coulomb’s experience on this project motivated him to establish a scientific basis for geotechnical and structural engineering; however the Caribbean heat exacted a lasting toll on his health.
Soon after returning to France, Coulomb began a series of studies “to determine, as far as a combination of mathematics and physics will permit, the influence of friction and cohesion in some problems of statics.” The report of these studies reads like a catalog of the difficulties that Coulomb undoubtedly encountered in Martinique — walls toppled by unstable slopes, crushed masonry columns, broken beams, collapsed arches, and the like. Few had the knowledge required to understand this work when it was first published, but Coulomb’s report is now considered as the beginning of modern structural analysis.
Coulomb is best known for a series of experiments he conducted to characterize the nature of the attractive force arising from a static electrical charge, which form the basis for Coulomb’s law. To carry out these experiments, Coulomb used this torsion balance of his own design. Coulomb is less widely known for his experiments that characterized, for the first time, the shear force exerted by a fluid moving tangentially to a solid surface.
Again, using his torsion balance, Coulomb determined that the shear force exerted by the fluid depends on the velocity of the fluid motion relative to the disk, and it is independent of the pressure force that acts perpendicular to the surface of the disk, unlike friction. Engineers used this result when designing the Ourcq Canal, built in 1804 to bring water into Paris.
Charles Augustin Coulomb is one of the 72 engineers and scientists named on the Eiffel Tower.
