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"This paper introduced a nonlinear finite element model using Msc.MARC to study behavior of concrete columns partially confined with metal sheet strips under uniaxial compression. The concrete and the metal sheet parts were modeled using the linear Mohr-Coulomb yield criterion and the Von-Mises yield criterion, respectively. Behaviors of the interface (bonding) material, both in the normal direction and the parallel direction to the interface, were modeled as a bilinear function based on the cohesive energy and the crack widths. The columns in this study had circular cross sections with the diameter of 15 cm and the height of 75 cm, wrapped around by 5 cm metal sheet strips. The results from 3D finite element modeling were analyzed for internally induced stresses and strains. The predicted column behavior was compatible with observed experimental data. The detailed mechanisms that were difficult to visualize during the laboratory experiments could be obtained from the analysis. It was revealed that the area of confinement and the number of applied metal sheet layers were important factors to the strength increase. The discrete confinement system was shown to be a promising alternative to the one-piece full-wrap system."

"The shear key is an important part of a precast segmental concrete bridge. Aside from its function of contributing to the distribution of shear force from one concrete segment to another, it helps to join precast concrete segments to become a complete bridge structure and provide continuity of movement for vehicles and pedestrian traffic. This numerical study discusses the behavior of a full-scale shear key connection without epoxy joining two concrete blocks representing segmental precast concrete at which two external forces load the blocks. Ferro Casting Ductile (FCD) is used as the metal shear key material where the shear key consists of two parts, a male and a female shear key. Numerical simulation is conducted using the ANSYS academic package, with nonlinear analysis implemented accordingly. The appropriate constitutive materials in relation to the numerical program, both for concrete and FCD, are taken from the appropriate literature. Two criteria are employed in the study; failure of the concrete block and yielding of the shear key that follows the von Mises criterion. Shear key connection system capacity is evaluated by applying different magnitudes of horizontal force. The validation of two numerical simulation studies is conducted by two experimental programs that cover laboratory experimentation of full-scale shear keys connecting two concrete blocks. The numerical and experimental results produce an almost similar relation of shear stress at the male shear key and vertical displacements of the upper block relative to the lower concrete block. Finally, a contour of shear key shear stress as a function of the different magnitudes of equivalent prestressing and different quality of concrete compressive strength is proposed."

"Penggunaan pecahan kaca dalam beton umumnya terbentur oleh reaksi kimia yang dihasilkan antara agregat gelas dan semen yang disebut Alkali-Silicate Reaction (ASR). Belakangan ini sudah ditemukan terobosan-terobosan untuk mengatasi hal itu. Penggunaan pecahan gelas bekas botol sebagai pengganti agregat alami beton untuk aplikasi konstruksi diharapkan mengurangi ketergantungan terhadap sumber agregat kasar alami. Skripsi ini mendalami aplikasi agregat kasar kaca dalam beton struktural dari segi kuat tekan dan kuat lentur serta susut, dengan fokus pada penggunaan limbah botol berwarna hijau. Dari hasil pengujian yang dilakukan, ditemukan bahwa keberadaan agregat kasar kaca dalam beton secara umum memperkecil kuat tekan, menambah kuat lentur, dan mengurangi susut beton.

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The usage of glass as a concrete aggregate in construction applications may reduce the dependence towards natural aggregate sources despite the presence of Alkali-Silicate Reaction (ASR) long-term effects. This study observes the compressive, flexural, and shrinkage properties of concrete with glass coarse aggregate, focusing in the exclusive usage of green-colored glass by neglecting the short-term effects of Alkali Silicate Reaction. Samples are made with 0%, 10%, 20%, 30%, and 50% of glass coarse aggregate replacement ratios. The results show that generally the increase of glass coarse aggregate presence in concrete decreases the compressive strength, increases the flexural strength and reduces the shrinkage effects of the glass coarse aggregate concrete."

"Limbah sisa adukan beton dan limbah kaca seringkali menjadi sampah dan berpotensi merusak lingkungan karena sifatnya yang sulit terurai. Padahal kedua bahan tersebut mempunyai potensi untuk dimanfaatkan, salah satunya sebagai pengganti agregat dan semen pada paving block. Tujuan penelitian ini adalah mengetahui seberapa besar pengaruh penambahan limbah adukan beton dan serbuk kaca terhadap sifat-sifat mekanik paving block. Pembuatan paving block dibuat dari limbah adukan beton, semenPC type I, dan serbuk kaca yang berasal dari sisa botol heinkein dan anker bir. Benda uji penelitian dibuat dengan perbandingan komposisi semen dan agregat 1:4,5 dengan 4 perlakuan subtitusi serbuk kaca yaitu 0%, 10%, 20%, dan 30% dari berat semen. Pengujian kuat tekan dan kuat lentur dilakukan pada hari ke-7,14,28 sedangkan pengujian penyerapan air dilakukan pada hari ke-14, 28, 49 dan 56.Dari hasil pengujian, didapatkan bahwa penambahan serbuk kaca 10% dari berat semen mempunyai komposisi terbaik untuk menghasilkan kekuatan yang optimum. Dimana kuat tekan paving block pada umur 28 hari mencapai 13,625 Mpa dan mengalami peningkatan sebesar 25,86% dari paving block tanpa mengunakan campuran serbuk kaca.

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Residual concrete sludge waste and glass waste is often a waste and potentially damaging to the environment because it is difficult to unravel. Yet, both materials have the potential to be used, as a substitute for aggregate and cement on paving block for example. The purpose of this study was to determine how much impact from the addition of waste concrete and glass powder on the mechanical properties of paving block. Paving blocks were made ​​of concrete waste, Portland Cement type I, and glass powder taken from the rest of heinkein and Anker beer bottles. Research specimens were made ​​with cement and aggregate composition ratio of 1:4,5 and different amount of substitution using glass powder. Glass powder ratios are as follow: 0%, 10%, 20%, and 30% of cement weight. Compressive and flexural strength testing were performed on day 7, 14, 28 while the water absorption test were performed on day 14, 28, 49 and 56.

From the test results, it was found that the specimen with the addition of glass powder by 10% of cement weight has the best composition resulted in producing optimum power. Compressive strength of paving blocks at day 28 reached 13.625 MPa, produced an increase by 25,86% compared to the paving block without using mixture of glass powder."

"[ ABSTRAK Kaca merupakan sumber silika amorphous yang baik serta memiliki komposisi kimia dan reaktivitas yang tepat untuk melakukan reaksi Pozzolan. Sehingga muncul lah ide untuk menggunakan kaca sebagai agregat kasar pada beton. Pada penelitian ini, sampel yang dibuat adalah dua jenis beton, yaitu Portland dan Geopolimer dengan variasi substitusi kaca sebanyak 0%, 25%, 50%, 100%. Pengujian yang dilakukan adalah uji tekan dan pengamatan foto makro. Komposisi beton, sejarah perlakuan, dan suhu curing memberi pengaruh signifikan pada nilai kuat tekan yang dihasilkan. Kesimpulan yang didapatkan adalah beton Portland dan beton geopolimer dengan substitusi kaca sebesar 50% memiliki kuat tekan tertinggi, dan pasta geopolimer dapat melekat pada kaca namun pasta semen tidak.

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ABSTRACT

Glass are good source of amorphous silica and it also has good chemistry composition and precise reactivity to make Pozzolan reaction. So there was an idea to use glass as coarse aggregate in concrete. In this research, two types of concrete will be made, which are Portland concrete and geopolymer concrete with variation of waste glass substitution as much as 0%, 25%, 50%, 100%. The conducted tests are pressure test and macro photos observations. Concrete composition, treatment history, and curing temperature gave significant influence on their compressive strength. The conclusions are both portland and geopolymer concrete with 50% waste glass substitution has the highest compressive strength, and geopolymer paste could adhered to glass but cement paste could not.;Glass are good source of amorphous silica and it also has good chemistry composition and precise reactivity to make Pozzolan reaction. So there was an idea to use glass as coarse aggregate in concrete. In this research, two types of concrete will be made, which are Portland concrete and geopolymer concrete with variation of waste glass substitution as much as 0%, 25%, 50%, 100%. The conducted tests are pressure test and macro photos observations. Concrete composition, treatment history, and curing temperature gave significant influence on their compressive strength. The conclusions are both portland and geopolymer concrete with 50% waste glass substitution has the highest compressive strength, and geopolymer paste could adhered to glass but cement paste could not.;Glass are good source of amorphous silica and it also has good chemistry composition and precise reactivity to make Pozzolan reaction. So there was an idea to use glass as coarse aggregate in concrete. In this research, two types of concrete will be made, which are Portland concrete and geopolymer concrete with variation of waste glass substitution as much as 0%, 25%, 50%, 100%. The conducted tests are pressure test and macro photos observations. Concrete composition, treatment history, and curing temperature gave significant influence on their compressive strength. The conclusions are both portland and geopolymer concrete with 50% waste glass substitution has the highest compressive strength, and geopolymer paste could adhered to glass but cement paste could not.;Glass are good source of amorphous silica and it also has good chemistry composition and precise reactivity to make Pozzolan reaction. So there was an idea to use glass as coarse aggregate in concrete. In this research, two types of concrete will be made, which are Portland concrete and geopolymer concrete with variation of waste glass substitution as much as 0%, 25%, 50%, 100%. The conducted tests are pressure test and macro photos observations. Concrete composition, treatment history, and curing temperature gave significant influence on their compressive strength. The conclusions are both portland and geopolymer concrete with 50% waste glass substitution has the highest compressive strength, and geopolymer paste could adhered to glass but cement paste could not.;Glass are good source of amorphous silica and it also has good chemistry composition and precise reactivity to make Pozzolan reaction. So there was an idea to use glass as coarse aggregate in concrete. In this research, two types of concrete will be made, which are Portland concrete and geopolymer concrete with variation of waste glass substitution as much as 0%, 25%, 50%, 100%. The conducted tests are pressure test and macro photos observations. Concrete composition, treatment history, and curing temperature gave significant influence on their compressive strength. The conclusions are both portland and geopolymer concrete with 50% waste glass substitution has the highest compressive strength, and geopolymer paste could adhered to glass but cement paste could not., Glass are good source of amorphous silica and it also has good chemistry composition and precise reactivity to make Pozzolan reaction. So there was an idea to use glass as coarse aggregate in concrete. In this research, two types of concrete will be made, which are Portland concrete and geopolymer concrete with variation of waste glass substitution as much as 0%, 25%, 50%, 100%. The conducted tests are pressure test and macro photos observations. Concrete composition, treatment history, and curing temperature gave significant influence on their compressive strength. The conclusions are both portland and geopolymer concrete with 50% waste glass substitution has the highest compressive strength, and geopolymer paste could adhered to glass but cement paste could not.]"