Akademik Veri Yönetim Sistemi
International Symp. on Innovations in Civil Engin. and Technology (ICIVILTECH 2019), Afyonkarahisar, Türkiye, 23 - 25 Ekim 2019, cilt.1, ss.285-295
Chemical admixtures are used to achieve desired
properties in concrete construction as a common method. However, the dosing of
the additives must be adjusted very well.
Mixtures that are used at different ratios adversely affect the strength
and durability of the concrete. In this study, the effects of the usage
together of plasticizer and set accelerator additives in different dosages were
investigated on mortar. Three combinations are prepared. One of the combinations
is recommended optimal dose of preparing the chemical additives. And the others
are reduced and increased mixtures. Accelerator takes value in %0,5 to %2 and
the plasticizer takes value in %1 to %3. The water cement ratio is selected
0.50 as constant. In the investigation unit weight, ultrasonic pulse velocity,
comprehensive strength, setting time tests and microstructure analysis tests
were performed in three different dosage mixtures and the obtained data were
evaluated. As a result of the tests carried out, the use of the admixtures in
different dosages caused decrement in physical properties of the concrete.
Especially the existence of admixtures more than %3 totally, it was decreased
the results significantly. 7-day comprehensive strength has indicated 22,98 MPa in the combination of
accelerator %2 and plasticizer %3 when 31,93 MPa in control sample that has no
additives. In the 28-day values it is recorded that combination as given ratios
result is 37,82 MPa when the control sample result is 43,55 MPa. So, we can say
that using combination of admixtures in several doses changes the expected strength
negatively. Therefore, as a result the coexistence of additives must be
sensitively controlled, and the necessary dosage adjustments must be made in
production.