STRUCTURAL PROPERTIES OF FLYASH CONCRETE

Abstract

the large amount of flyash which is produced by the thermal power stations is basically a waste material and its disposal presents a formidable problem. This has resulted in research in various fields regarding the utiliza-tion of flyash, a direct application being the introcliction of flyash in concrete in order to reduce cement consumption.] Most of the existing literature bears testimony to --1 the fact that work has mainly been concentrated on the com-pressive strength of flyash concretes, The necessity of investigating the tensile and bond strengths predominates in light of the previous statement. The work embodied in this dissertation incorporates direct compressive, equivalent cube, direct tensile, flexural, split cylinder, split prism and bond strength tests. These experiments were conducted in order to make a comparison v&th the existing test results and to provide a basis for comparison of work in the future, since the testing of a large number of specimens has not been undertaken in this p ro gramm e, It has been found that 1 - 20% of flyash is the optimum value for intended substitution, In general the .compressive and tensile strengths decreases and the bond .strength increases v~ci.th the addition of flyash. The (iv) maximum strength that can be obtained is 80% - 916 for the former and 1.3 - 1.5 times for the later. In all, three mixes - Ml (1:2:4) , M2 (1;1-,5.- 3) , M3 (.1:1:2) were tested using l0%, 15 , 20% and 2T substitution of flyash. The di meter of plain bars used for testing of bond were of 6, 10, 12 and 16 mm 0 resp ecti vely