RESEARCH ON THE EFFECT OF FLY ASH CONTENT AND PLASTICIZER ADDITIVE ON THE STRENGTH CHARACTERISTICS OF CEMENT-FLY ASH MORTAR

Abstract

This paper presents the results of an experimental investigation assessing the impact of fly ash content and plasticizer additives on the strength and flowability characteristics of mortar. In this study, fly ash was used to partially replace cement, with replacement contents of 0%, 5%, 10%, and 15%. The fine aggregate was natural sand, and the water-to-binder ratio was specified as 0.3. The mortar was supplemented with plasticizer at a rate of 1.0%, 1.5%, and 2.0%. The samples were cured in room conditions (temperature 27±2°C, humidity 95±5%) until the day of testing. The results indicated that the compressive strength of the 7-day samples was inversely proportional to the amount of fly ash that replaced cement. After 56 days of curing, the samples containing 5%, 10%, and 15% fly ash replacing cement have higher compressive strength than the control sample without fly ash. The ratio of plasticizers also affects the fluidity of the fresh mortar. When the ratio of plasticizers increases, the fluidity of mortar increases.