| dc.description.abstract | Conventional concrete casting on the main structural component of multi-storey buildings requires perfect compaction, among others, by using the vibrator tool. In some of the structural components which meet in a point knot or joint, such as beam-column connections, it usually has a very dense reinforcement detail (the amount of intersecting rebars is very much, because of the demands on the strength of structural components). The impact of these conditions pose new problems in the concrete casting. These conditions need to be addressed in order to prevent post-casting of porous concrete, because the distance and composition of reinforcement that is too tight may cause the concrete mix unable to fill the cavities or crevices between rebars. There are several solutions to address these issues, among others: gradation of coarse aggregate in the concrete mix is made in smaller sizes and using the technology of Self Compacting Concrete (SCC). SCC technology is currently being developed to use for a wide variety of purposes as building construction material, therefore this research is intended to develop the technology by substituting substance-added silica fume and superplasticizer with a specific composition into the concrete mix. To make the SCC mixture, this research uses the added material in the form of silica fume with the use of the highest percentage of 10%, and superplasticizer with percentage variation ranging between 0.8%, 1.0%, 1.2%, 1.4%, and 1,6%. Superplasticizer serves to give workability in concrete with reduced water demand up to 30%, while the silica fume serves to provides the concrete binding process that is long and capable of reducing water infiltration in concrete (bleeding). SCC requires good flowability of the fresh concrete with slump-flow value of at least 50 cm and a maximum of 75 cm. In general, the achieved slump value is very high (more than 20 cm).
From the SCC research, the optimum value of compressive strength in test subject SCC-3 has been found, resulting in 43,063 MPa, the result is greater than the planned compressive strength which is 41.4 MPa. When viewed from the strength development of the compressive strength of non-SCC concrete (BN) in the testing age of 7, 14, 21, and 28 days, the concrete is experiencing a significant increase in compressive strength with the average percentage of 20,6%. In test subject SCC-5 for compressive strength development is experiencing a slowdown and had a increase percentage of about 10,4%. While the optimum results of tensile strength/split has been found in test subject SCC-3 with a value of 11,172 MPa, and when viewed with the requirement on SNI 03-2491-2002, the SCC-3 tensile strength result fall within the requirement. When viewed, the strength development of tensile strength/split of non-SCC concrete (BN) in the testing age of 7, 14, 21, and 28 days is experiencing a significant increase with the average percentage of about 16,188%, and when compared with test subject SCC-5, the result of the strength development of tensile strength/split is experiencing a slowdown with the increase percentage of about 6,676%. | en_US |
