scholarly journals Study of Proportional Variation of Geopolymer Concrete which Self Compacting Concrete

2019 ◽  
Vol 2 (2) ◽  
pp. 65
Author(s):  
Purwanto P. ◽  
Himawan Indarto
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Power Plant ◽  
Portland Cement ◽  
Fine Aggregate ◽  
Geopolymer Concrete ◽  
Conventional Concrete ◽  
Basic Characteristics ◽  
Carbon Dioxide Co2 ◽  
Proportional Variation

Portland cement production process which is the conventional concrete constituent materials always has an impact on producing carbon dioxide (CO2) which will damage the environment. To maintain the continuity of development, while maintaining the environment, Portland cement substitution can be made with more environmentally friendly materials, namely fly ash. The substitution of fly ash material in concrete is known as geopolymer concrete. Fly ash is one of the industrial waste materials that can be used as geopolymer material. Fly ash is mineral residue in fine grains produced from coal combustion which is mashed at power plant power plant [15]. Many cement factories have used fly ash as mixture in cement, namely Portland Pozzolan Cement. Because fly ash contains SiO2, Al2O3, P2O3, and Fe2O3 which are quite high, so fly ash is considered capable of replacing cement completely.This study aims to obtain geopolymer concrete which has the best workability so that it is easy to work on (Workable Geopolymer Concrete / Self Compacting Geopolymer Concrete) and obtain the basic characteristics of geopolymer concrete material in the form of good workability and compressive strength. In this study, geopolymer concrete is composed of coarse aggregate, fine aggregate, fly ash type F, and activators in the form of NaOH and Na2SiO3 Be52. In making geopolymer concrete, additional ingredients such as superplastizer are added to increase the workability of geopolymer concrete. From this research, the results of concrete compressive strength above fc' 25 MPa and horizontal slump values reached 60 to 80 centimeters.

scholarly journals Study on Setting & Strength Characteristic of GGBS based Geopolymer Concrete by Blending of Fly Ash and Metakaoline

2020 ◽  
Vol 13 (1) ◽  
pp. 117-122
Author(s):  
Addepalli Mallinadh Kashyap ◽  
Tanimki Chandra Sekhar Rao ◽  
N.V. Ramana Rao
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Portland Cement ◽  
Sodium Hydroxide ◽  
Sodium Silicate ◽  
Setting Time ◽  
Engineering Properties ◽  
Geopolymer Concrete ◽  
Conventional Concrete ◽  
New Material

Carbon dioxide is liberated in huge amounts by the manufacturing of Portland Pozzolana Cement. Normally, conventional concrete is manufactured with Portland cement, which acts as a binder. The production of cement emits CO2 into the atmosphere, which is a green house gas and causes the environmental pollution. Considering this as a serious environmental problem, there is a need to develop sustainable alternatives to Portland cement utilizing the industrial byproducts such as fly ash, ground granulated blast furnace slag and Metakaoline which are pozzolonic in nature. It has been established that fly ash can replace cement partially. In this context, a new material was developed known as ‖Geopolymer‖. In this study, the various parameters on the short term engineering properties of fresh and hardened properties of Geopolymer Mortar were studied. In the present investigation, cement is replaced by geopolymer source material and water is replaced by alkaline activator consisting of Sodium Silicate and Sodium Hydroxide of molarity (12M). The ratio of sodium silicate to sodium hydroxide adopted was 2.5. The test results showed that final setting time decreases as the GGBS content in the mix increases and also increase in compressive strength. Where as in the case of metakaoline, as the content increases, there is a decrease in compressive strength and setting times of the geopolymer concrete.

scholarly journals PENGARUH WAKTU CURING TERHADAP KUAT TEKAN GEOPOLIMER BERBASIS FLY ASH

2019 ◽  
Vol 2 (1) ◽  
pp. 50
Author(s):  
Andrie Harmaji ◽  
Claudia Claudia ◽  
Lia Asri ◽  
Bambang Sunendar ◽  
Ahmad Nuruddin
Keyword(s):  
Compressive Strength ◽  
Fourier Transform ◽  
Fly Ash ◽  
Power Plant ◽  
Functional Groups ◽  
Room Temperature ◽  
Three Dimensional ◽  
Fine Aggregate ◽  
Alkali Activator ◽  
Infra Red

Abstract:. Suralaya power plant produces fly ash about 219.000 ton per year. Fly ash contents of silica and alumina as major components that can be used as precursors for geopolymer, a three dimensional networks aluminosilicate polymers. This research aim is to utilize fly ash for geopolymer made by mixing fly ash, fine aggregate, and alkali activator in a cubic mould and curing was carried out at room temperature for 7 and 28 days. After 28 days of curing the compressive strength of geopolymer reached 41.70 MPa. XRD characterization shows Albite (NaAlSi3O8) formation which has similarity to geopolymer compound. Fourier Transform Infra Red spectra show siloxo and sialate bond. These are typical functional groups that are found in geopolymer materials.Keyword: geopolymer, fly ash, aluminosilicate, alkali activator, albite, siloxo, sialateAbstrak: Pembangkit Listrik Tenaga Uap (PLTU) Suralaya menghasilkan fly ash (abu terbang) sekitar 219.000 ton per tahun. Fly ash memiliki silika dan alumina sebagai komponen utama yang dapat digunakan sebagai prekursor untuk geopolimer, suatu material polimer aluminosilikat tiga dimensi. Penelitian ini bertujuan untuk memanfaatkan fly ash untuk geopolimer yang dibuat dengan mencampur fly ash, agregat halus, dan aktivator alkali dalam cetakan kubik dan pengawetan dilakukan pada suhu kamar selama 7 dan 28 hari. Setelah 28 hari curing kekuatan tekan geopolimer mencapai 41,70 MPa. Karakterisasi XRD menunjukkan pembentukan Albite (NaAlSi3O8) yang memiliki kemiripan dengan senyawa geopolimer. Hasil spektroskopi Fourier Transform Infra Red (FTIR) menunjukkan ikatan siloxo dan sialate yang merupakan gugus fungsional khas yang ditemukan dalam geopolimer.Kata Kunci: geopolimer, abu terbang, aluminosilikat, alkali aktivator, albite, siloxo, sialate

scholarly journals The Effectiveness of Fly Ash as a Substitute of Cement For Marine Concrete

2018 ◽  
Vol 4 (4) ◽  
pp. 702 ◽  
Author(s):  
Armin Naibaho
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Portland Cement ◽  
Coarse Aggregate ◽  
Base Material ◽  
Sand Fly ◽  
Fine Aggregate ◽  
Additional Material ◽  
Marine Concrete ◽  
Average Compressive Strength

The purpose of this research is to know the effectiveness of fly ash waste in marine concrete related to the average compressive strength to be used as a substitute for cement. The test is done for concrete base material, namely: coarse aggregate (gravel), fine aggregate (sand), fly ash, cement (PC = Portland Cement), water and additional material (superplasticizer). 10 cylinders were given each treatment with (0 %, 10 %, 20 %, 25 %) percentage of fly ash addition. The samples then soaked for 26 days in seawater. At 28th day, the sample was subjected to a compression test. Based on the results of analysis and discussion, then obtained: (1) The use of 10% fly ash amount will produce the biggest compressive strength  =  65.84 MPa; (2) When compared with the average compressive strength, the sample without using fly ash (0 %) has compressive power 62.02 MPa and 6.16 % increase in average compressive strength on the addition of 10 % fly ash 65.84 MPa, but in addition to 20 % fly ash there was a decrease of 9.13 % (56.36 MPa) and in addition of 25 % fly ash the average compressive strength decrease to 22.49 % (48.07 MPa).

scholarly journals Effect of Elevated Temperature on Alkali Activated Slag and Fly Ash based Geopolymer Concrete

2020 ◽  
Vol 9 (4) ◽  
pp. 1241-1250
Keyword(s):  
Compressive Strength ◽  
Elevated Temperature ◽  
Fly Ash ◽  
Flexural Strength ◽  
Portland Cement ◽  
Ordinary Portland Cement ◽  
Geopolymer Concrete ◽  
Base Materials ◽  
Activated Slag ◽  
Alkali Activated

Activated Slag (AAS) and Fly Ash (FA) based geopolymer concrete a new blended alkali-activated concrete that has been progressively studied over the past years because of its environmental benefits superior engineering properties. Geopolymer has many favorable characteristics in comparison to Ordinary Portland Cement. Many base materials could be utilized to make geopolymer with the convenient concentration of activator solution. In this study, the experimental program composed of two phases; phase on divided into four groups; Group one deliberated the effect of sodium hydroxide molarity and different curing condition on compressive strength. Group two studied the effect of alkali activated solution (NaOH and Na2SiO3) content on compressive strength and workability. The effect of sand replacement with slag on compressive strength and workability was explained in group three. Group four studied the effect of slag replacement with several base materials Fly Ash (FA), Ordinary Portland Cement (OPC), pulverized Red Brick (PRB), and Meta Kaolin (MK). Phase two contains three mixtures from phase one which had the highest compressive strength. For each mixture, the fresh concrete test was air content. In addition the hardened concrete tests were the compressive strength at 3, 7, 28, 90, 180, and 365 days, the flexural strength at 28, 90, and 365 days, and the young's modulus at 28, 90, and 365 days. Moreover; the three mixtures were exposed to elevated temperature at 100oC, 300oC, and 600oC to study the effect of elevated temperature on compressive and flexural strength.

scholarly journals PEMANFAATAN LIMBAH FLY ASH DAN BOTTOM ASH DARI PLTU SUMSEL-5 SEBAGAI BAHAN UTAMA PEMBUATAN PAVING BLOCK

2019 ◽  
Vol 11 (1) ◽  
pp. 1067
Author(s):  
Hadi Winarno ◽  
Damris Muhammad ◽  
Yudha Gusti Wibowo
Keyword(s):  
Operating System ◽  
Compressive Strength ◽  
Fly Ash ◽  
Power Plant ◽  
Portland Cement ◽  
Solid Waste ◽  
Coal Combustion ◽  
Bottom Ash ◽  
Steam Power ◽  
Class B

Fly ash and bottom ash are solid waste from coal combustion in the operating system of Steam Power Plant (PLTU). The research was conducted by combining fly ash and bottom ash with an adhesive consisting of portland cement. Based on the tests performed the maximum mixture obtained with cement samples, fly ash and bottom ash is 1: 2: 2. Paving blocks made from fly ash and bottom ash have compressive strength values resulting in compressive strength values of 50.52 MPa. This value indicates that the sample is in the class of paving blocks A. Paving Block made from fly ash and bottom ash also has a very good average air absorption value, in a combination of suitable cement mixtures, fly ash and bottom ash (1: 2: 2) the average air absorption value is still 5.06%. This value shows that the sample is in class B paving blocks.

scholarly journals Durability of Fly Ash Based Geopolymer Concrete against Chloride and Sulphuric Acid Attack

2020 ◽  
Vol 5 (6) ◽  
pp. 1507-1510
Author(s):  
Kartika Ilma Pratiw ◽  
Saloma .
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Portland Cement ◽  
Sulphuric Acid ◽  
Test Object ◽  
Sulfate Solution ◽  
Geopolymer Concrete ◽  
Acid Attack

The aim of this study was to replace Portland cement with fly ash-based geopolymer as precursors, to serve as a binder after reacting with NaOH and Na2SiO3 activators. The test object existed in the form of a cube of size 50 x 50 x 50 mm. The mortar was treated for 28 days and then immersed in a sulfate solution at similar interval using the wet-dry cycle and non-cycle methods. The compressive strength of the geopolymer mortar was estimated as 45.90 MPa before immersion. Therefore, 35.79 MPa, 41.09 MPa, as well as 37.85 MPa were reported after submersion in the respective solutions of 5% H2SO4, Na2SO4, and NaCl, using wet-dry cycle. Based on the non-cycle approach, the resulting strength was 37.36 MPa, 43.05 MPa and 39.52 MPa correspondingly.

scholarly journals Compressive Strength of Fly-Ash-Based Geopolymer Concrete by Gene Expression Programming and Random Forest

2021 ◽  
Vol 2021 ◽  
pp. 1-17 ◽  
Author(s):  
Mohsin Ali Khan ◽  
Shazim Ali Memon ◽  
Furqan Farooq ◽  
Muhammad Faisal Javed ◽  
Fahid Aslam ◽  
...  
Keyword(s):  
Gene Expression ◽  
Compressive Strength ◽  
Fly Ash ◽  
Random Forest ◽  
Gene Expression Programming ◽  
Curing Temperature ◽  
Fine Aggregate ◽  
Geopolymer Concrete ◽  
Soft Computing Techniques ◽  
Water Ratio

Fly ash (FA) is a residual from thermal industries that has been effectively utilized in the production of FA-based geopolymer concrete (FGPC). To avoid time-consuming and costly experimental procedures, soft computing techniques, namely, random forest regression (RFR) and gene expression programming (GEP), are used in this study to develop an empirical model for the prediction of compressive strength of FGPC. A widespread, reliable, and consistent database of compressive strength of FGPC is set up via a comprehensive literature review. The database consists of 298 compressive strength data points. The influential parameters that are considered as input variables for modelling are curing temperature T , curing time t , age of the specimen A , the molarity of NaOH solution M , percent SiO2 solids to water ratio %   S / W in sodium silicate (Na2SiO3) solution, percent volume of total aggregate (   %   A G ), fine aggregate to the total aggregate ratio F / A G , sodium oxide (Na2O) to water ratio N / W in Na2SiO3 solution, alkali or activator to the FA ratio A L / F A , Na2SiO3 to NaOH ratio N s / N o , percent plasticizer ( %   P ), and extra water added as percent FA E W % . RFR is an ensemble algorithm and gives outburst performance as compared to GEP. However, GEP proposed an empirical expression that can be used to estimate the compressive strength of FGPC. The accuracy and performance of both models are evaluated via statistical error checks, and external validation is considered. The proposed GEP equation is used for sensitivity analysis and parametric study and then compared with nonlinear and linear regression expressions.

Preliminary Study of Pressed Lightweight Geopolymer Block Using Fly Ash, Portland Cement and Recycled Lightweight Concrete

2016 ◽  
Vol 718 ◽  
pp. 184-190
Author(s):  
Patcharapol Posi ◽  
Piyawat Foytong ◽  
Pearploy Thongjapo ◽  
Natakorn Thamultree ◽  
Phongsathon Boontee ◽  
...  
Keyword(s):  
Fly Ash ◽  
Portland Cement ◽  
Lightweight Concrete ◽  
Concrete Block ◽  
Concrete Aggregate ◽  
Fine Aggregate ◽  
Geopolymer Concrete ◽  
Lignite Fly Ash ◽  
Concrete Blocks ◽  
Preliminary Study

In this research, the properties of pressed lightweight fly ash geopolymer concrete block containing Portland cement and recycled lightweight concrete aggregate. The recycled lightweight concrete aggregate (RLCA) was crushed and classified as coarse aggregate (CA), medium aggregate (MA) and fine aggregate (FA). The RLCA with CA : MA : FA of 30 : 30 : 40 by weight was used to reduce the weight of concrete block. Lightweight geopolymer concrete block was produced from lignite fly ash, NaOH, Na2SiO3, RCLA and PC. The lightweight geopolymer concrete blocks with 28-day compressive strengths between 2.0 and 14.1 MPa and densities between 1130 and 1370 kg/m3 were obtained.

The Use of Fly Ash in the Production of Concrete and Products Based on it

2020 ◽  
Vol 309 ◽  
pp. 8-13
Author(s):  
Fedor Kapustin ◽  
Andrey Vishnevsky
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Power Plant ◽  
Single Layer ◽  
Early Time ◽  
Fine Aggregate ◽  
Technological Parameters ◽  
Discharge System ◽  
Aerated Concrete ◽  
Reduced Density

Reftinskaya state district power plant owned by Enel company and located in Russia produces up to 5 million tons of fly ash and slag annually when burning multi-ash coal of the Ekibastuz basin. A new system of dry ash removal works at the power plant; it includes the laying system of wet ashes and slags on the dump and the discharge system from the silo storage facility up to 1 million tons of ash per year. The chemical-mineral and grain composition data, properties and their correspondence to Russian standard 25818 in order to use ash in the production of concrete and products based on it are presented. The experience of production and application of autoclaved aerated ash concrete of reduced density is considered. It is shown that fly ash of Reftinskaya state district power plant is an effective substitute for quartz sand in the technology of cellular concrete. Its application opens up additional opportunities for aerated concrete with a density of 300-400 kg/m3 production. To optimize the structure and properties it is proposed to introduce an additive of natural gypsum in the amount of 3-5 % of the mass of dry components into the autoclave aerated concrete. The produced aerated ash concrete had a thermal conductivity of 0.075-0.100 W/m∙K which allows it to be used for erection of single-layer enclosing structures without additional insulation. Fly ash can also be used as part of heavy and fine-aggregate concrete replacing a part of Portland cement and sand. The addition of ash in an amount of up to 25 % by weight of cement improves the workability and reduces the demixing of the concrete mix. Ash introduction up to 10 % increases the compressive strength of concrete at an early time and after 28 days of normal hardening, an increase of it up to 25 % decreases the compressive strength, reduces the conductivity, but increases the shrinkage of concrete. The optimum ash content up to 100 kg/m3 for steamed concrete and not more 50 kg/m3 for normal hardening concrete. Compliance with the optimal composition and technological parameters of the production of concrete structures using ash enables to produce concrete of F200-F300 grade by frost resistance.

scholarly journals Systematic multiscale models to predict the compressive strength of fly ash-based geopolymer concrete at various mixture proportions and curing regimes

PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0253006
Author(s):  
Hemn Unis Ahmed ◽  
Ahmed Salih Mohammed ◽  
Azad A. Mohammed ◽  
Rabar H. Faraj
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Sodium Silicate ◽  
Mean Squared Error ◽  
Curing Temperature ◽  
Coefficient Of Determination ◽  
Fine Aggregate ◽  
Geopolymer Concrete ◽  
Palm Oil Fuel Ash ◽  
Binder Ratio

Geopolymer concrete is an inorganic concrete that uses industrial or agro by-product ashes as the main binder instead of ordinary Portland cement; this leads to the geopolymer concrete being an eco-efficient and environmentally friendly construction material. A variety of ashes used as the binder in geopolymer concrete such as fly ash, ground granulated blast furnace slag, rice husk ash, metakaolin ash, and Palm oil fuel ash, fly ash was commonly consumed to prepare geopolymer concrete composites. The most important mechanical property for all types of concrete composites, including geopolymer concrete, is the compressive strength. However, in the structural design and construction field, the compressive strength of the concrete at 28 days is essential. Therefore, achieving an authoritative model for predicting the compressive strength of geopolymer concrete is necessary regarding saving time, energy, and cost-effectiveness. It gives guidance regarding scheduling the construction process and removal of formworks. In this study, Linear (LR), Non-Linear (NLR), and Multi-logistic (MLR) regression models were used to develop the predictive models for estimating the compressive strength of fly ash-based geopolymer concrete (FA-GPC). In this regard, a comprehensive dataset consists of 510 samples were collected in several academic research studies and analyzed to develop the models. In the modeling process, for the first time, twelve effective variable parameters on the compressive strength of the FA-GPC, including SiO2/Al2O3 (Si/Al) of fly ash binder, alkaline liquid to binder ratio (l/b), fly ash (FA) content, fine aggregate (F) content, coarse aggregate (C) content, sodium hydroxide (SH)content, sodium silicate (SS) content, (SS/SH), molarity (M), curing temperature (T), curing duration inside ovens (CD) and specimen ages (A) were considered as the modeling input parameters. Various statistical assessments such as Root Mean Squared Error (RMSE), Mean Absolute Error (MAE), Scatter Index (SI), OBJ value, and the Coefficient of determination (R2) were used to evaluate the efficiency of the developed models. The results indicated that the NLR model performed better for predicting the compressive strength of FA-GPC mixtures compared to the other models. Moreover, the sensitivity analysis demonstrated that the curing temperature, alkaline liquid to binder ratio, and sodium silicate content are the most affecting parameter for estimating the compressive strength of the FA-GPC.

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