"Over the last few years an increasing amount of interest has been shown in the use of prestressed concrete. As is true in many new methods of design or construction, the properties of existing materials to be used sometimes fail to meet all the desirable characteristics, and certain modifications might be advantageous. This is certainly true of prestressed concrete design and construction, in which a lower modulus of elasticity accompanied by a minimum loss in strength would be desirable. If a lower modulus of elasticity could be obtained for concrete, a lower prestressing load could be used and still maintain proper crack control in prestressed concrete beams and slabs. It would also be an advantage in highway construction and design, in that it would provide a more flexible pavement, longer slab design and easier riding comfort.
Researchers have been looking for an additive to lower the modulus or elasticity of concrete with a minimum loss in strength. The use of fly-ash as an additive is not new. Fly-ash has been used with success as an additive to certain lime-soil mixtures and concrete for the purpose of changing their physical characteristics and for reasons of economy.
Since fly-ash has been used with success as an additive to change the characteristics for concrete and lime-soil mixtures, and since it is a waste product from the combustion of bituminous coal and is readily available in abundance in industrial areas, it would seem reasonable to investigate the possibility of using fly-ash as an additive and determine its effect on the modulus of elasticity in concrete for prestressing operations.
The object of this investigation is to determine the effect of varying percentages of fly-ash on the modulus of elasticity of concrete mortar "--Introduction, pages 1-2.
Carlton, E. W.
Hansen, Peter G., 1927-2010
Rankin, Rolfe M., 1892-1974
Best, John, 1925-2015
Civil, Architectural and Environmental Engineering
M.S. in Civil Engineering
Missouri School of Mines and Metallurgy
v, 67 pages
© 1959 Billy Lee Atchley, All rights reserved.
Thesis - Open Access
Fly ash -- Testing
Concrete -- Additives
Prestressed concrete -- Elastic properties
Print OCLC #
Electronic OCLC #
Link to Catalog Record
Atchley, Bill L., "The effects of fly-ash on dynamic modulus of elasticity of a concrete mortar" (1959). Masters Theses. 5550.