J. Augustine DeSazilly
Encyclopedia
J. Augustine DeSazilly was a French engineer
.
In the early 1850s, DeSazilly published a paper postulating the "profile of equal resistance," a major theoretical advance in the technology of masonry
gravity dams, based on the hydrostatic force
exerted by a given height of water in relation to the weight of masonry used in the dam's construction (estimated at 150 pounds per cubic foot). DeSazilly considered two extreme conditions, a filled reservoir
and an empty reservoir, and created a model for equalizing stresses on the masonry across every horizontal cross section
. He developed a vertical cross section in which the stresses at the upstream face of a masonry gravity dam with the reservoir empty are equal to those at the downstream face with the reservoir filled. His hypothesis provided a means of calculating the minimum amount of material that could be used while assuring stability. Although he himself never carried out the construction of a dam on this "profile of equal resistance," it was used in 1858 to build the Furens Dam across the Loire River.
DeSazilly also developed a process of surface drainage
for building on a slope, and contributed to the building of railways, roads, and bridges.
Engineer
An engineer is a professional practitioner of engineering, concerned with applying scientific knowledge, mathematics and ingenuity to develop solutions for technical problems. Engineers design materials, structures, machines and systems while considering the limitations imposed by practicality,...
.
In the early 1850s, DeSazilly published a paper postulating the "profile of equal resistance," a major theoretical advance in the technology of masonry
Masonry
Masonry is the building of structures from individual units laid in and bound together by mortar; the term masonry can also refer to the units themselves. The common materials of masonry construction are brick, stone, marble, granite, travertine, limestone; concrete block, glass block, stucco, and...
gravity dams, based on the hydrostatic force
Statics
Statics is the branch of mechanics concerned with the analysis of loads on physical systems in static equilibrium, that is, in a state where the relative positions of subsystems do not vary over time, or where components and structures are at a constant velocity...
exerted by a given height of water in relation to the weight of masonry used in the dam's construction (estimated at 150 pounds per cubic foot). DeSazilly considered two extreme conditions, a filled reservoir
Reservoir
A reservoir , artificial lake or dam is used to store water.Reservoirs may be created in river valleys by the construction of a dam or may be built by excavation in the ground or by conventional construction techniques such as brickwork or cast concrete.The term reservoir may also be used to...
and an empty reservoir, and created a model for equalizing stresses on the masonry across every horizontal cross section
Cross section (physics)
A cross section is the effective area which governs the probability of some scattering or absorption event. Together with particle density and path length, it can be used to predict the total scattering probability via the Beer-Lambert law....
. He developed a vertical cross section in which the stresses at the upstream face of a masonry gravity dam with the reservoir empty are equal to those at the downstream face with the reservoir filled. His hypothesis provided a means of calculating the minimum amount of material that could be used while assuring stability. Although he himself never carried out the construction of a dam on this "profile of equal resistance," it was used in 1858 to build the Furens Dam across the Loire River.
DeSazilly also developed a process of surface drainage
Drainage
Drainage is the natural or artificial removal of surface and sub-surface water from an area. Many agricultural soils need drainage to improve production or to manage water supplies.-Early history:...
for building on a slope, and contributed to the building of railways, roads, and bridges.
External links
- A diagram of DeSazilly's "profile of equal resistance" may be viewed in The History of Large Federal Dams: Planning, Design, and Construction (Government Printing Office, 2005), p. 52 online.