Pengaruh Sulfat terhadap Kuat Tekan Beton dengan Variasi Bubuk Kaca Substitusi Sebagian Pasir dengan W/C 0,4 dan 0,5

The Concrete buildings which located in certain location susceptible to sulfate attack. The sulfate can damage the buildings, one of the alternative that can be used to improve the durability of concrete due to sulfate attack by reducing the porosity, the glass powder as a sample that can be use. The glass powder has a pozolanic character that can fill the empty voids in the concrete. The purpose of this study was to determine the effect of glass powder as fine aggregate replacement in concrete that exposed and not exposed to sulfate attack. In this research, some tests were done to determine the compressive strength by replacing sand with 0%, 5%, 10%, 15% and 20% of glass powder. The cylinder specimen was soaked with plain water and 5% MgSO4 solution with 7, 21 and 28 days, using water-cement ratio 0,4 and 0,5. The result shows that the smallest percentage reduction in the compressive strength due to sulfate attack was founded in 20% of glass content, for w/c = 0,4 in 7 days was 0,57% and for w/c = 0,5 was 1,45%., The highest compressive strength of concrete that was soaked with plain water and 5% MgSO4 solution was founded in 20% of glass content, for w/c = 0,4 in 28 days was 44,72 MPa and 43,85 MPa and then for w/c = 0,5 was 37,80 MPa and 36,45 MPa. So if the content of glass increase the compressive strength will increase and the percentage reduction in compressive strength due to sulfate attack will decrease

Pengaruh Sulfat terhadap Kuat Tekan Beton dengan Variasi Bubuk Kaca Substitusi Semen dengan W/C 0,4 dan 0,5

The aggressive environment can damage concrete especially sulfate attack which would decrease compressive strength of concrete and also cause corrosion. Therefore, the additive was added into concrete mixture. A glass powder is an additive that contains binding substance in reaction with water and accelerate concrete hardening.This final project will discuss the effect of glass powder as replacement of cement in concrete mixture to concrete compressive strength that soaked in water and water containing sulfate. In this research, concrete sample is cylindrical with diameter of 15 cm and heigth of 30 cm which consisting of normal concrete, 5%, 10%, 15% and 20% glass powder in concrete mixture with w/c 0,4 and 0,5. Soaking is done in two ways, ie soaked in water and water containing sulfate. The concrete compressive strength test was performed at 7,21 and 28 days. The result of this research, the concrete that soaked in water and water containing sulfate has the highest compressive strength on 5% glass powder with w/c 0.4 of 44,92 MPa and 43,78 MPa on 28 days and 5% glass powder with w/c 0,5 of 35,86 MPa and 34,54 MPa on 28 days. Besides of that, the attack of sulfate can decrease compressive strength of concrete which have been soaked in water containing sulfate. The smallest reduction of compressive strength occured on 20% glass powder with w/c 0,4 of 1,70% on 28 days and 20% glass powder with w/c 0,5 of 2,99% on 28 days. It can be concluded, despite the large increase glass powder in concrete mixture can decrease concrete compressive strength, but the effect of sulfate to concrete compressive strength is getting smaller

Pengaruh Sulfat terhadap Kuat Tekan Beton dengan Variasi Bubuk Kaca Substitusi Sebagian Pasir dengan W/c 0,60 dan 0,65

In order to minimize the damage of concrete structures due to external influences , especially due to sulfate attack that occured naturally in soil and groundwater where the structure is located, and to utilize glass wastes in big cities, a proportion of sand was replaced by glass powder. Two different mix design is calculated based on ACI method (w/c 0.60 and 0.65 ) , with 0%,5%, 10%, 15% and 20% passed a #8 sieve glass powder replacements investigated. Concrete soaked for 7 , 21 and 28 days with 2 types of water were plain water and a 5% sulfate solution . The test results showed that compared to normal concrete for both mix designs, the slump of 20% glass sand replacement concrete was the smallest than the other. Compressive strength of concrete with glass powder substitution is higher than the design compressive strength, and continues to increase with the addition of glass powder content. At 28 days, the compressive strength of specimens with various amount of glass sand replacement were all higher than that of the design strength when soaked in sulfate solution