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for 25 times. Pour the geopolymer until full and then flatten the surface of it.
7. Put the concrete mix with the mold into the the oven at 80°C for 24
hours. 8.
After that, geopolymer concrete is released from the mold and put into the oven at 23°C over the life of the testing that has been
established 14 and 28 days.
4.8. Slump Test
The aim of the test is to assess the free flow of geopolymer concrete mix into the horizontal direction without hindrance. This test also intends to determine the
workability in the process of geopolymer concrete mix. How to test Slump
1. Put the mixture into the Abrams funnel cone in 3 layers. For each
layer, pound the mixture for 25 times.
2. After flatten the upper surface of the mixture keep it for approximately
1 minute.
3.
Lifted the Abrams cone vertically.
4.
Then the decline that occurred in the concrete is measured with a ruler.
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4.9. Curing Process
Curing process is done by put the mixture with the mold into the oven at 80° C for 24 hours. The aim of this step is to keep the temperature of geopolymer
concrete constant in the medium heat because polymerization reaction needs medium heat during the curing. From the chemical reaction, geopolymer
concrete will produces water that will be removed during the curing process. Therefore, after remove the mixture from the oven and mold, geopolymer
concrete directly put into the oven at temperature 23°C. So the environment does not affect the process of concrete geopolimer condensation.
4.10. Compressive Strength and Modulus of Elasticity Tests
Concrete compressive strength and modulus of elasticity testing were conducted at the Building Material
’s Laboratory of Civil Engineering Program, Faculty of Engineering, Universitas Atma Jaya Yogyakarta. Tests carried out
using Compression Testing Machine CTM with brand ELE.
4.11. Schedule of the Final Project
The research should be scheduled to make sure that the research can be done on time. The schedule of the research can be seen in Table 4.2
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Table 4.2. Schedule of the Research
Activity 2014-2015
September October November January
February March
Determine the topic of the final
project Wrote the
proposal Seminar
Proposal Implementation
Research and Data Analysis
Wrote the final project
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CHAPTER V DISCUSSION
5.1. Result and Discussion of material Investigation
5.1.1. Investigate the Fine Aggregate to Obtain the Results.
1. Investigation of the organic matter content.
Investigate the organic matter content is important because the organic matter content can reduce the quality of the concrete. To know whether it is
possible to be used or not can be seen from the color of the sample. The relationship between the color and possibility of fine aggregate can be seen
from Table 5.1. Table 5.1 Relationship between the Color of the Solution and Organic
Mater Content
No. Color
Organic Mater Information
5 Light flaxen
Less organic matter content
Good to be used 8
Flaxen Rather much
organic matter content
Can be used
11 Dark Yellow
A lot of organic matter content
Not really good to be used
14 Dark Orange
A lot of organic matter content
Cannot be used 16
Dark Red A lot of organic
matter content Cannot be used
