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Abstrak :
Inovasi pada teknologi beton berkembang dan meningkat pesat. Modifikasi dilakukan pada penelitian beton untuk dapat menghasilkan beton yang kuat, bernilai ekonomis, dan ramah terhadap lingkungan. Oleh karena itu tujuan penelitian ini adalah untuk merancang campuran beton yang kuat, ekonomis dan ramah lingkungan atau sebagai Sustainable Construction Material. Hal ini dapat dilakukan dengan memanfaatkan limbah beton sebagai bahan subtitusi material beton yaitu agregat kasar serta limbah slag sebagai bahan subtitusi material beton yaitu semen. Dalam penelitian ini, akan dipelajari sifat karakteristik dari bahan limbah tersebut dan mengetahui efek penggunaannya terhadap kekuatan beton. Pada penelitian ini, kuat tekan beton dengan komposisi Ground Granulated Blast Furnace Slag (GGBFS) yang berbeda yaitu 0%, 25%, 50%, 75%, dan 25% tanpa superplasticizer akan diteliti pada campuran beton dengan komposisi agregat kasar 40% terhadap agregat alami. Semakin tinggi komposisi GGBFS maka kuat tekan semakin rendah. Penggunaan 50% GGBFS mempunyai kuat tekan 24,834 MPa. Dengan penggantian 50% GGBFS ini pun dapat mengurangi penggunaan semen, sehingga campuran beton tersebut dapat bernilai ekonomis dan mengurangi emisi CO2. Penggunaan superplasticizer berpengaruh, terlihat pada komposisi 25% dengan superplasticizer pada umur awal lebih tinggi dibandingkan komposisi yang sama tanpa superplasticizer.

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Innovations in concrete technology are developing and increasing rapidly. Several modifications have been made in the concrete research with the purpose to produce a strong, economically valuable, and environmentaly friendly concrete. Therefore, this study aims at giving a design of the strong, economically valuable, and environmentally friendly concrete or known as a Sustainable Construction Material. It can be realized by changing concrete waste into a concrete substitution material -i.e. coarse aggregate-and slag waste into a concrete substituion material -i.e. cement .This study then explores the characteristics of these materials and the effects of their use on the strength of concrete. The investigated compressive strength of the concrete includes the Ground Granulated Blast Furnace Slag (GGBFS) compositions of 0%, 25%, 50%, 75%, and that of 25% without a superplasticizer; they are identifiable in the concrete mixture with the coarse aggregate composition of 40% against natural aggregates. Based on the data analysis, this study has found that the higher the GGBFS composition, the lower the compressive strength. The use of 50% GGBFS has a compressive strength of 24,834 MPa. This study has also discovered that the replacement of 50% GGBFS can cut the use of cement which in turn will lead to the emission and CO2 reductions. In conclusion, a superplasticizer gives an impact. The GGBFS composition of 25% with the early superplasticizer is higher than the one without superplasticizer.

Abstrak :
Ground granulated blast furnace slag (ggbs) is a waste material generated from iron production, and is one of the cementitious materials that can be used to replace part of the cement in concrete. The aim of this research was to determine the effects of the water-binder ratios and levels of ggbs in concrete, with regard to the activation energy, which is needed for predicting the concrete’s strength. A number of mixtures with different water-binder ratios (ranging from 0.30 to 0.51), ggbs levels, and curing temperatures were cast and tested at 0.5, 1, 2, 4, 8, 16, and 32 days. The activation energies were determined using the American society for testing and materials (ASTM) standard C1074, and the Freiesleben Hansen and Pedersen (FHP) method. The results of the experiment showed that the apparent activation energy was relatively independent of the water-binder ratio, and mainly affected by the ggbs level in the concrete. Higher ggbs levels in the concrete resulted in the higher apparent activation energies.

Abstrak :
Karya ini bertujuan untuk mempelajari fisika-kimia fenomena yang terjadi selama proses karbonasi pasta semen dengan tingkat semen substitusi yang tinggi dengan penambahan mineral dan perlawanan mereka terhadap jenis serangan dilakukan sesuai dengan peraturan Perancis. Kita mempelajari kinetika karbonasi di awal-awal tes. Menggunakan termogravimetri, kita kemudian mempelajari pengaruh pra-kondisi pada kinetika difusi CO2. Sebuah kajian eksperimental dilakukan pada referensi campuran beton dengan konsistensi perbandingan E / C = 0,3, E / C = 0,4 dan pasta semen Portland dengan diganti sebagian dengan semen terak dapur tinggi. Penelitian difokuskan pada daya tahan pasta semen portlandite, terutama perlawanan mereka terhadap karbonasi yang dinilai di laboratorium menggunakan tes dipercepat, pada kesetaraan pasta semen normal dengan substitusi semen terak dapur tinggi (75%) dan pada parameter komposisi dan mikrostruktur mengontrol kinetika dari karbonasi. Hasil penelitian menunjukkan bahwa campuran pasta semen dengan tingkat substitusi semen terak dapur tinggi yang tinggi (75%) dapat diterapkan. Selain studi eksperimental tersebut, kami juga menentukan pengaruh pengeringan pada sifat pengendalian kinetika karbonasi dipercepat dari campuran pasta semen (porositas, portlandite konten dan derajat saturasi air). Hasil penelitian menunjukkan bahwa kinetika pengeringan meningkat dengan derajat substitusi semen dengan penambahan mineral. Mereka juga mempertimbangkan kembali relevansi dari pra-kondisi sampel selama tes percepatan karbonasi dilakukan sesuai dengan standar XP Perancis P 18-458. ......The present work aims to study the physic-chemical phenomena occurring during the process of carbonation of cement paste with high substitution rates of cement by mineral additions and their resistance against this type of attack according to the French standard. We study the kinetics of carbonation in the early days of the test. Using thermogravimetric, we then study the influence of preconditioning on the kinetics of CO2 diffusion. An experimental campaign was conducted on reference concrete mixtures prepared with common cements with E/C=0,3, E/C=0,4 and Portland cement pastes prepared by substituting part of cement by blast-furnace slag. The study focused on the cements portlandite durability, especially their resistance against carbonation is commonly assessed in laboratory using accelerated tests, on the equivalence of ordinary cement pastes with substitution of cement by slag (75%) and on the composition and microstructure parameters controlling the kinetics of carbonation. The results show that cement paste mixtures with high substitution rates of cement by blast-furnace slag (75%) could be replaced. In addition to the experimental study, we determined the effect of drying on the properties controlling of the accelerated carbonation kinetics of the studied concrete mixtures (porosity, portlandite content and water saturation degree). The results show that the kinetics of drying increases with the degree of substitution of cement by mineral additions. They also reconsider the relevance of the preconditioning of the samples during accelerated carbonation test conducted according to the French standard XP P 18-458.