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concrete and bleeding concrete separation excessively to achieve the higher concrete strength.
Characteristics of Workability Consistency
Workability is depends on the composition of the fresh concrete, physical characteristic from the mixture and aggregate.
Mobility Ease to mix the mixture, put the mixture into the mold, and
compaction. Compact ability
Ease to compact the mixture so that the air cavities can be reduced. Stability
The ability of the concrete to always homogeneous, always binding coherent, and there will be no grain separation segregation and
bleeding. Finish ability
Ease of the concrete to reach the final stage which is hardened with good conditions.
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3.11. The Age of Concrete
The age of concrete is important to be considered in the experiment because the strength of the concrete will rise for every day. At the first time the strength
of the concrete will be increase very fast and after that it will be relatively small in the age of 28
days. The age of concrete is calculated from the time when the concrete is removed from the mold.
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CHAPTER IV RESEARCH METHODOLOGY
4.1. Research Metodology
Research methodology is the process to collect information and data about the topic through surveys, questionnaires, interviews, practice to the laboratory
research and so on to get the result that needed. The type of this method is research. The objective of this research is to know
the compressive strength and modulus of elasticity of geopolymer concrete with metakaolin and silica fume. The first step is make the activator. The way to make
the activator is mixed NaOH 0.03 with 1000ml of water and wait for 24 hours. After that, the NaOH 12 M will be mixed with Na
2
SiO
3.
Pasta geopolymer is done. Metakaolin, silica fume and aggregate are mixed together in a big place.
After all, the pasta geopolymer will be pour into the big place that already filled by the aggregate, metakaolin and silica fume. After mix all of the materials and
alkali activator, the geopolymer pasta will be ready to put into the mold. There are two tests that will be used to test the geopolymer concrete. First, test
the compressive strength of the specimen. There will be 9 samples to test the compressive strength in 14 days in small cylinder. Second, test the modulus
elasticity and the compressive strength of the 9 big cylinders. The size of the
