scispace - formally typeset
Search or ask a question
Book ChapterDOI

Mix Design of Fly Ash Based Geopolymer Concrete

01 Jan 2015-The Indian Concrete Journal (Springer, New Delhi)-Vol. 82, Iss: 5, pp 7-14
TL;DR: In this paper, an experimental investigation has been carried out for the gradation of geopolymer concrete and a mix design procedure is proposed on the basis of quantity and fineness of fly ash, quantity of water, grading of fine aggregate, fine to total aggregate ratio.
Abstract: Geopolymer is a new development in the world of concrete in which cement is totally replaced by pozzolanic materials like fly ash and activated by highly alkaline solutions to act as a binder in the concrete mix. For the selection of suitable ingredients of geopolymer concrete to achieve desire strength at required workability, an experimental investigation has been carried out for the gradation of geopolymer concrete and a mix design procedure is proposed on the basis of quantity and fineness of fly ash, quantity of water, grading of fine aggregate, fine to total aggregate ratio. Sodium silicate solution with Na2O = 16.37 %, SiO2 = 34.35 % and H2O = 49.28 % and sodium hydroxide solution having 13 M concentration were maintained constant throughout the experiment. Water-to-geopolymer binder ratio of 0.35, alkaline solution-to-fly ash ratio of 0.35 and sodium silicate-to-sodium hydroxide ratio of 1.0 by mass were fixed on the basis of workability and cube compressive strength. Workability of geopolymer concrete was measured by flow table apparatus and cubes of 150 mm side were cast and tested for compressive strength after specified period of oven heating. The temperature of oven heating was maintained at 60 °C for 24 h duration and tested 7 days after heating. It is observed that the results of workability and compressive strength are well match with the required degree of workability and compressive strength. So, proposed method is used to design normal and standard geopolymer concrete.
Citations
More filters
Journal ArticleDOI
TL;DR: In this paper, an innovative machine learning techniques namely gene expression programming (GEP) and multi-expression programming (MEP) are employed for forecasting the compressive strength of FGC.

48 citations

Journal ArticleDOI
TL;DR: In this paper, a new mix design method for fly ash geopolymer mortars activated using combined sodium silicate and sodium hydroxide solutions is presented, which can be applied to generate relevant mix design charts for various types of geopolymers binders.

44 citations

Journal ArticleDOI
TL;DR: In this paper, three artificial intelligence (AI) techniques namely; artificial neural network (ANN), adaptive neuro-fuzzy interface (ANFIS), and gene expression programming (GEP) are used to establish a reliable and accurate model to estimate the compressive strength (f_c^') of fly-ash based geopolymer concrete (FGPC).
Abstract: The ultrafine fly-ash (FA) is a hazardous material collected from coal productions, which has been proficiently employed for the manufacturing of geo-polymer concrete (GPC). In this paper, the three artificial intelligence (AI) techniques namely; artificial neural network (ANN), adaptive neuro-fuzzy interface (ANFIS), and gene expression programming (GEP) are used to establish a reliable and accurate model to estimate the compressive strength (f_c^') of fly-ash based geopolymer concrete (FGPC). A database of 298 instances is developed from the peer-reviewed published work. The database consists of the ten most prominent explanatory variables and f_c^' of FGPC as a response parameter. The statistical error checks and criteria suggested in the literature are considered for the verification of the predictive strength of the models. The statistical measures considered in this study are MAE, RSE, RMSE, RRMSE, R, and performance index (ρ). These checks verify that ANFIS predictive model gives an outstanding performance followed by GEP and ANN predictive models. In the validation stage, the coefficient of correlation (R) for ANFIS, GEP, and ANN model is 0.9783, 0.9643, and 0.9314 respectively. All three models also fulfill the external verification criterion suggested in the literature. Generally, GEP predictive model is ideal as it delivers a simplistic and easy mathematical equation for future use. The k-fold cross-validation (CV) of the GEP model is also conducted, which verifies the robustness of the GEP predictive model. Furthermore, the parametric study is carried via proposed GEP expression. This confirms that the GEP model accurately covers the influence of all the explanatory variables used for the prediction of f_c^' of FGPC. Thus, the proposed GEP equation can be used in the preliminary design of FGPC.

44 citations

Journal ArticleDOI
TL;DR: In this article, a systematic approach for selecting mix proportions for fly ash and GGBS-based geopolymer concrete is presented, where the main parameters considered were binder content and alkaline solution/binder ratio for various combinations of fly ash.
Abstract: This paper presents a systematic approach for selecting mix proportions for fly ash and GGBS-based geopolymer concrete. Very little information is available on complete methodology in designing the fly ash and GGBS-based geopolymer mix. The fly ash and GGBS were activated using sodium silicate and sodium hydroxide as alkaline activator solution. The Na2SiO3/NaOH (alkaline activator) ratio was taken as 2.5 and the concentration of NaOH solution was maintained at 8 M. The main parameters considered in this study were binder content and alkaline solution/binder ratio for various combinations of fly ash and GGBS. The variables considered in this experimentation include: binder content (360, 420 and 450 kg/m3), proportions of fly ash and GGBS (70–30, 60–40 and 50–50), alkaline solution/binder ratios (0.45, 0.50, 0.55 and 0.60) and curing condition (outdoor curing and oven curing). Results concluded that the GGBS content, alkaline solution/binder ratio and curing condition are found to be most influenti...

43 citations

Journal ArticleDOI
TL;DR: In this article, gene expression programming (GEP) was used to estimate compressive strength of geopolymer concrete (GPC) made by employing fly-ash (FA) like waste material.
Abstract: For the production of geopolymer concrete (GPC), fly-ash (FA) like waste material has been effectively utilized by various researchers. In this paper, the soft computing techniques known as gene expression programming (GEP) are executed to deliver an empirical equation to estimate the compressive strength fc′ of GPC made by employing FA. To build a model, a consistent, extensive and reliable data base is compiled through a detailed review of the published research. The compiled data set is comprised of 298 fc′ experimental results. The utmost dominant parameters are counted as explanatory variables, in other words, the extra water added as percent FA (%EW), the percentage of plasticizer (%P), the initial curing temperature (T), the age of the specimen (A), the curing duration (t), the fine aggregate to total aggregate ratio (F/AG), the percentage of total aggregate by volume ( %AG), the percent SiO2 solids to water ratio (% S/W) in sodium silicate (Na2SiO3) solution, the NaOH solution molarity (M), the activator or alkali to FA ratio (AL/FA), the sodium oxide (Na2O) to water ratio (N/W) for preparing Na2SiO3 solution, and the Na2SiO3 to NaOH ratio (Ns/No). A GEP empirical equation is proposed to estimate the fc′ of GPC made with FA. The accuracy, generalization, and prediction capability of the proposed model was evaluated by performing parametric analysis, applying statistical checks, and then compared with non-linear and linear regression equations.

42 citations

References
More filters
Journal ArticleDOI
TL;DR: In the last few years, technological progress has been made in the development of new materials such as "geopolymers" and new techniques, such as ''sol-gel'' as mentioned in this paper, opening up new applications and procedures and transforming ideas that have been taken for granted in inorganic chemistry.
Abstract: Spectacular technological progress has been made in the last few years through thedevelopment of new materials such as «geopolymers», and new techniques, such as «sol-gel». New state-of-the-art materials designed with the help of geopolymerization reactions are opening up new applications and procedures and transforming ideas that have been taken for granted in inorganic chemistry. High temperature techniques arc no longer necessary to obtain materials which are ceramic-like in their structures and properties

3,178 citations

Journal ArticleDOI
TL;DR: In this article, a statistical study of the effect on the polymerization process of the molar ratio of the component oxides and the water content of the mixture showed the latter to be a critical parameter.

933 citations

Journal ArticleDOI
TL;DR: In this article, fly ash-based geopolymer concrete was developed to reduce greenhouse gas emissions, and the test results showed the effects of various parameters on the properties of the concrete.
Abstract: To reduce greenhouse gas emissions, efforts are needed to develop environmentally friendly construction materials. This paper presents the development of fly ash-based geopolymer concrete. In geopolymer concrete, a by-product material rich in silicon and aluminum, such as low-calcium (ASTM C 618 Class F) fly ash, is chemically activated by a high-alkaline solution to form a paste that binds the loose coarse and fine aggregates, and other unreacted materials in the mixture. The test results presented in this paper show the effects of various parameters on the properties of geopolymer concrete. The application of geopolymer concrete and future research needs are also identified.

797 citations

Journal Article
TL;DR: In this article, the authors discuss the increase use of large volumes of fly ash and other supplementary cementing materials in the construction industry and its role in reducing these emissions, since the manufacture of portland cement contributes significantly to carbon dioxide emissions.
Abstract: Environmental issues will play a leading role in the sustainable development of the cement and concrete industry in the 21st century. The World Earth Summits in Rio de Janeiro, Brazil in 1992, and Kyoto, Japan in 1997, have made it abundantly clear that unchecked increased emission of greenhouse gases to the atmosphere is no longer environmentally and socially acceptable for overall sustainable development. The primary greenhouse gas emissions discussed in the sessions of the above conferences are carbon dioxide emissions. Other greenhouse gases such as nitrous oxide and methane, are of serious concern, but the amount involved is relatively small compared with that of carbon dioxide. Consequently, developed countries are considering regulations and mandatory quotas on the emission of these gases, and the main thrust is to stabilize these emissions to the 1990 level by the year 2010. Since the manufacture of portland cement contributes significantly to carbon dioxide emissions, this article discusses the increase use of large volumes of fly ash and other supplementary cementing materials in the construction industry and its role in reducing these emissions.

226 citations