#TITLE_ALTERNATIVE#

• Main Author: BAYU SETIAWAN (NIM : 13705004); Dosen Pembimbing : Dr. Ir. Aditianto Ramelan, INDRA
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/16046
• Institution: Institut Teknologi Bandung

Silica Fume and CaCO3 are admixtures that often be used for increasing concrete’s compressive strength. This experiment’s objective is to create High Strength Concrete by using silica fume made by PT Sika Indonesia and CaCO3 made by PT Brataco. For concretes to have good workability, a superplasticizer is used: Sikament®-NN, also a <br /> <br /> <br /> <br /> <br /> product of SIKA Indonesia. <br /> <br /> <br /> <br /> <br /> Ratio of both admixtures in this experiment are constant variable 9.15w/o, used in watercement ratio: 0.2, 0.25, 0.3, 0.34. Cement, aggregates, and superplasticizer used were 95, 105.3, 2.35 in grams. The curing methods are air curing and water curing in 14, 21, 28, 35 days. Another experiment has been conducted to compare the compressive strength of concrete with CaCO3 admixture with variety of ratio: 8, 10, dan 12 w/o, water cured in 7 days. Compression tests were using Tarnogrocki Universal Testing in laboratory of Metallurgy and Materials Engineering ITB. The lowest compressive strength obtained in concrete speciment with silica fume, air cured in 28 days, and water-cement ratio 0.34, which is 5.2 MPa. The highest compressive strength obtained by concrete with CaCO3, water cured in 35 days, and water-cement ratio 0.25, which is 55.8 MPa. Beside compression test, SEM characterization tests were also conducted for both types of concrete <br /> <br /> <br /> <br /> <br /> with admixture silica fume or CaCO3 and for silica fume. It showed that silica fume has been agglomerated. <br /> <br /> <br /> <br /> <br /> This experiment shows that concretes with CaCO3 produce higher compressive strength than concretes with silica fume. Water curing relatively produces higher compressive strength than air curing. In 35 days with water curing, the increase of strength relatively continuous. Standard compressive strength for High Strength Concrete, higher than 50 MPa, is reached with adding CaCO3, w/c 0.25, and water cured in 35 days. Compressive strength of concrete <br /> <br /> <br /> <br /> <br /> with CaCO3 will decrease if exceed 10%.