Document Type
Thesis
Date of Award
5-31-1991
Degree Name
Master of Science in Civil Engineering - (M.S.)
Department
Civil and Environmental Engineering
First Advisor
Methi Wecharatana
Second Advisor
John W. Liskowitz
Abstract
Fly ash-cement mortar, constituting of fly ash, cement and sand, vary in strength characteristics from conventional cement sand mortar. Out of many parameters effecting the compressive strength characteristics of fly ash-cement mortar, four were investigated in this study. They are particle size and its distribution, weathering of fly ash, moisture content & water/cementitious ratio and mix proportioning.
Class F fly ashes from three different sources were used in this study. The particle size distribution and moisture content of fly ashes were investigated by standard ASTM methods. The unconfined compressive strength of mortar was obtained by testing 2"x2"x2" test cubes conforming to the ASTM standard testing procedures.
The results of the tests indicated that there is a direct relationship between particle size distribution and compressive strength of mortar. The finest particles, of diameters 0-10 micron are the most influential on strength development.
The water/cementitious ratio should be clearly defined as the ratio of weight of water to the weight of cement and total fly ash content of the mix. The optimum water content for the maximum compressive strength depend on the fly ash content in the paste.
The results show very clearly that weathering of fly ash brings about some physico-chemical changes in the fly ash rheology.
Neither cement content nor fly ash content alone but, rather the combination of these two parameters determine the compressive strength of a mortar mix.
Recommended Citation
Ratnaweera, Poorna Rajeswari, "Influence of fly ash characteristics on compressive strength of mortar" (1991). Theses. 2604.
https://digitalcommons.njit.edu/theses/2604
