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

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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Compressive Strength of Sustainable Geopolymer Concrete Composites: A State-of-the-Art Review

Sustainability ◽

10.3390/su132413502 ◽

2021 ◽

Vol 13 (24) ◽

pp. 13502

Author(s):

Hemn Unis Ahmed ◽

Azad A. Mohammed ◽

Serwan Rafiq ◽

Ahmed S. Mohammed ◽

Amir Mosavi ◽

...

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Sodium Hydroxide ◽

Sodium Silicate ◽

Construction Material ◽

Curing Temperature ◽

Geopolymer Concrete ◽

Palm Oil Fuel Ash ◽

Silicate Content ◽

Binder Ratio

The building industry, which emits a significant quantity of greenhouse gases, is under tremendous pressure due to global climate change and its consequences for communities. Given the environmental issues associated with cement production, geopolymer concrete has emerged as a sustainable construction material. Geopolymer concrete is an eco-friendly construction material that uses industrial or agricultural by-product ashes as the principal binder instead of Portland cement. Fly ash, ground granulated blast furnace slag, rice husk ash, metakaolin, and palm oil fuel ash were all employed as binders in geopolymer concrete, with fly ash being the most frequent. The most important engineering property for all types of concrete composites, including geopolymer concrete, is the compressive strength. It is influenced by different parameters such as the chemical composition of the binder materials, alkaline liquid to binder ratio, extra water content, superplasticizers dosages, binder content, fine and coarse aggregate content, sodium hydroxide and sodium silicate content, the ratio of sodium silicate to sodium hydroxide, the concentration of sodium hydroxide (molarity), curing temperature, curing durations inside oven, and specimen ages. In order to demonstrate the effects of these varied parameters on the compressive strength of the fly ash-based geopolymer concrete, a comprehensive dataset of 800 samples was gathered and analyzed. According to the findings, the curing temperature, sodium silicate content, and alkaline solution to binder ratio are the most significant independent parameters influencing the compressive strength of the fly ash-based geopolymer concrete (FA-BGPC) composites.

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Random Forest Modeling for Fly Ash-Calcined Clay Geopolymer Composite Strength Detection

Journal of Composites Science ◽

10.3390/jcs5100271 ◽

2021 ◽

Vol 5 (10) ◽

pp. 271

Author(s):

Priyanka Gupta ◽

Nakul Gupta ◽

Kuldeep K. Saxena ◽

Sudhir Goyal

Keyword(s):

Tensile Strength ◽

Compressive Strength ◽

Fly Ash ◽

Random Forest ◽

Mean Squared Error ◽

Absolute Error ◽

Curing Temperature ◽

Coefficient Of Determination ◽

Split Tensile Strength ◽

Calcined Clay

Geopolymer is an eco-friendly material used in civil engineering works. For geopolymer concrete (GPC) preparation, waste fly ash (FA) and calcined clay (CC) together were used with percentage variation from 5, 10, and 15. In the mix design for geopolymers, there is no systematic methodology developed. In this study, the random forest regression method was used to forecast compressive strength and split tensile strength. The input content involved were caustic soda with 12 M, 14 M, and 16 M; sodium silicate; coarse aggregate passing 20 mm and 10 mm sieve; crushed stone dust; superplasticizer; curing temperature; curing time; added water; and retention time. The standard age of 28 days was used, and a total of 35 samples with a target-specified compressive strength of 30 MPa were prepared. In all, 20% of total data were trained, and 80% of data testing was performed. Efficacy in terms of mean absolute error (MAE), root mean square error (RMSE), coefficient of determination (R2), and MSE (mean squared error) is suggested in the model. The results demonstrated that the RFR model is likely to predict GPC compressive strength (MAE = 1.85 MPa, MSE = 0.05 MPa, RMSE = 2.61 MPa, and R2 = 0.93) and split tensile strength (MAE = 0.20 MPa, MSE = 6.83 MPa, RMSE = 0.24 MPa, and R2 = 0.90) during training.

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

Advances in Civil Engineering ◽

10.1155/2021/6618407 ◽

2021 ◽

Vol 2021 ◽

pp. 1-17 ◽

Cited By ~ 1

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.

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Compressive Strength of Geopolymer Concrete Composites: Modeling and Comprehensive Systematic Review

10.21203/rs.3.rs-611987/v1 ◽

2021 ◽

Author(s):

Hemn Unis Ahmed ◽

Azad A. Mohammed ◽

Ahmed S. Mohammed

Keyword(s):

Systematic Review ◽

Compressive Strength ◽

Fly Ash ◽

Sodium Hydroxide ◽

Sodium Silicate ◽

Alkaline Solution ◽

Construction Material ◽

Assessment Tools ◽

Curing Temperature ◽

Geopolymer Concrete

Abstract The growing concern about global climate change and its adverse impacts on societies is putting severe pressure on the construction industry as one of the largest producers of greenhouse gases. Given the environmental issues associated with cement production, geopolymer concrete has emerged as a sustainable construction material. Geopolymer concrete is cementless concrete that uses industrial or agro by-product ashes as the main binder instead of ordinary Portland cement; this leads to being an eco-efficient and environmentally friendly construction material. Compressive strength is one of the most important mechanical property for all types of concrete composites including geopolymer concrete, and it is affected by several parameters like an alkaline solution to binder ratio (l/b), fly ash (FA) content, SiO2/Al2O3 (Si/Al) of the FA, fine aggregate (F) and coarse aggregate (C) content, sodium hydroxide (SH) and sodium silicate (SS) content, ratio of sodium silicate to sodium hydroxide (SS/SH), molarity (M), curing temperature (T), curing duration (CD) inside the oven and specimen ages (A). In this regard, a comprehensive systematic review was carried out to show the effect of these different parameters on the compressive strength of the fly ash-based geopolymer concrete (FA-GPC). In addition, multi-scale models such as Artificial Neural Network (ANN), M5P-tree (M5P), Linear Regression (LR), and Multi-logistic Regression (MLR) models were developed to predict the compressive strength of FA-GPC composites. For the first time, in the modeling process, twelve effective parameters including l/b, FA, Si/Al, F, C, SH, SS, SS/SH, M, T, CD, and A were considered the modeling input parameters. Then, the efficiency of the developed models was assessed by various statistical assessment tools like Root Mean Squared Error (RMSE), Mean Absolute Error (MAE), Scatter Index (SI), OBJ value, and the Coefficient of determination (R2). Results show that the curing temperature, sodium silicate content, and ratio of the alkaline solution to the binder content are the most significant independent parameters that influence on the compressive strength of the FA-GPC, and the ANN model has better performance for predicting the compressive strength of FA-GPC in compared to the other developed models.

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Study of Proportional Variation of Geopolymer Concrete which Self Compacting Concrete

Journal of Advanced Civil and Environmental Engineering ◽

10.30659/jacee.2.2.65-75 ◽

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.

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Artificial Intelligence Approaches for Prediction of Compressive Strength of Geopolymer Concrete

Materials ◽

10.3390/ma12060983 ◽

2019 ◽

Vol 12 (6) ◽

pp. 983 ◽

Cited By ~ 48

Author(s):

Dong Dao ◽

Hai-Bang Ly ◽

Son Trinh ◽

Tien-Thinh Le ◽

Binh Pham

Keyword(s):

Artificial Intelligence ◽

Compressive Strength ◽

Fly Ash ◽

Sodium Hydroxide ◽

Sodium Silicate ◽

Steel Slag ◽

Sodium Silicate Solution ◽

Silicate Solution ◽

Partial Replacement ◽

Geopolymer Concrete

Geopolymer concrete (GPC) has been used as a partial replacement of Portland cement concrete (PCC) in various construction applications. In this paper, two artificial intelligence approaches, namely adaptive neuro fuzzy inference (ANFIS) and artificial neural network (ANN), were used to predict the compressive strength of GPC, where coarse and fine waste steel slag were used as aggregates. The prepared mixtures contained fly ash, sodium hydroxide in solid state, sodium silicate solution, coarse and fine steel slag aggregates as well as water, in which four variables (fly ash, sodium hydroxide, sodium silicate solution, and water) were used as input parameters for modeling. A total number of 210 samples were prepared with target-specified compressive strength at standard age of 28 days of 25, 35, and 45 MPa. Such values were obtained and used as targets for the two AI prediction tools. Evaluation of the model’s performance was achieved via criteria such as mean absolute error (MAE), root mean square error (RMSE), and coefficient of determination (R2). The results showed that both ANN and ANFIS models have strong potential for predicting the compressive strength of GPC but ANFIS (MAE = 1.655 MPa, RMSE = 2.265 MPa, and R2 = 0.879) is better than ANN (MAE = 1.989 MPa, RMSE = 2.423 MPa, and R2 = 0.851). Sensitivity analysis was then carried out, and it was found that reducing one input parameter could only make a small change to the prediction performance.

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The Effect of Variation of Molarity of Alkali Activator and Fine Aggregate Content on the Compressive Strength of the Fly Ash: Palm Oil Fuel Ash Based Geopolymer Mortar

Advances in Materials Science and Engineering ◽

10.1155/2014/245473 ◽

2014 ◽

Vol 2014 ◽

pp. 1-13 ◽

Cited By ~ 17

Author(s):

Iftekhair Ibnul Bashar ◽

U. Johnson Alengaram ◽

Mohd Zamin Jumaat ◽

Azizul Islam

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Palm Oil ◽

Alkaline Solution ◽

Strength Development ◽

Fine Aggregate ◽

Palm Oil Fuel Ash ◽

Alkali Activator ◽

Fuel Ash ◽

Oil Fuel

The effect of molarity of alkali activator, manufactured sand (M-sand), and quarry dust (QD) on the compressive strength of palm oil fuel ash (POFA) and fly ash (FA) based geopolymer mortar was investigated and reported. The variable investigated includes the quantities of replacement levels of M-sand, QD, and conventional mining sand (N-sand) in two concentrated alkaline solutions; the contents of alkaline solution, water, POFA/FA ratio, and curing condition remained constant. The results show that an average of 76% of the 28-day compressive strength was found at the age of 3 days. The rate of strength development from 3 to 7 days was found between 12 and 16% and it was found much less beyond this period. The addition of 100% M-sand and QD shows insignificant strength reduction compared to mixtures with 100% N-sand. The particle angularity and texture of fine aggregates played a significant role in the strength development due to the filling and packing ability. The rough texture and surface of QD enables stronger bond between the paste and the fine aggregate. The concentration of alkaline solution increased the reaction rate and thus enhanced the development of early age strength. The use of M-sand and QD in the development of geopolymer concrete is recommended as the strength variation between these waste materials and conventional sand is not high.

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STUDI PENDAHULUAN BATAS MAKSIMUM KADAR LUMPUR PADA AGREGAT BETON GEOPOLIMER

Jurnal Poli-Teknologi ◽

10.32722/pt.v18i1.1283 ◽

2019 ◽

Vol 18 (1) ◽

Author(s):

Djedjen Achmad ◽

Desi Supriyan

Keyword(s):

Compressive Strength ◽

Concrete Aggregate ◽

Fine Aggregate ◽

Geopolymer Concrete ◽

Test Results ◽

Cement Concrete ◽

Flexural Tensile Strength ◽

Binder Ratio ◽

The Impact ◽

Water Binder Ratio

ABSTRACTHas been researched the impact of mud in aggregate on geopolymer concrete with studies using the cement concrete as a reference. In this study both of concrete are mixed with a variation of mud of 0%, 0.75%, 3% and 5.75% of the combined aggregate weight. Compressive strength of cement concrete is designed with a target of 300 kg / cm2 and geopolymer concrete is made with water binder ratio (w/b) 0.25, Molarity 12 M, the ratio of sodium silicate and sodium hydroxide 1.5. At the age of 3, 7, 14 and 28 day tested of compressive strength, while the spliting test, flexural tensile strength, and modulus of elasticity are tested at 28 days. From the test results, the higher mud content in aggregate , the mechanical properties of the concrete are decreased. Based on testing of compressive strength in cement concrete at 28 days, with a 3% mud content (the content of the reference mud) turns of compressive strength decreased by 77.356%. Of the percentage reduction on the compressive strength of the cement concrete, can be compared to the mud content in geopolymer concrete at 2.04%. Thus the maximum mud on geopolymer concrete aggregate is, for coarse aggregate of 0.68% and a maximum mud content for fine aggregate was 3.4%.Key words : Mud, aggregate, concrete, cement, geopolimer, strengthABSTRAKTelah diteliti dampak kadar lumpur pada agregat untuk beton geopolimer dengan penelitian menggunakan benda uji beton semen sebagai acuan dan beton geopolimer. Dalam penelitian ini ke dua beton tersebut dicampur dengan lumpur gabungan agregat kasar dan agregat halus dengan variasi 0 %, 0.75 %, 3 % dan 5,75 % dari berat agregat gabungan. Beton semen dirancang dengan target kuat tekan 300 kg/cm2 dan beton geopolimer dibuat dengan campuran water binder ratio (w/b) 0.25, Molaritas 12 M, perbandingan sodium silikat dan sodium hidroksida 1.5. Pada umur 3, 7, 14 dan 28 hari dilakukan uji kuat tekan, sedangkan uji kuat tarik belah, uji kuat tarik lentur, dan modulus elastisitas dilakukan pada umur 28 hari. Dari hasil uji terlihat bahwa semakin tinggi kadar lumpur pada agregat, karakteristik mekanis kedua beton tersebut mengalami penurunan. Berdasarkan pengujian kuat tekan pada beton semen umur 28 hari, dengan kadar lumpur 3 % (kadar lumpur referensi) ternyata beton semen mengalami penurunan kuat tekan sebesar 77.356 %. Dari persentase penurunan kuat tekan beton semen tersebut, diplot pada grafik kuat tekan beton geopolimer maka persentase kadar lumpur gabungan yang mengalami penurunan 77.356 % adalah 2.04 %. Dengan demikian kadar lumpur maksimum pada agregat beton geopolimer adalah, untuk agregat kasar sebesar 0.68 % dan kadar lumpur maksimum untuk agregat halus adalah 3.4 %.Kata kunci : Lumpur, agregat, beton, semen, geopolimer, kekuatan

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Properties Of Ferro-Geopolymer Mortar Slab Panels

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.l3160.1081219 ◽

2019 ◽

Vol 8 (12) ◽

pp. 1635-1641

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Experimental Research ◽

Ultimate Load ◽

Flexural Behavior ◽

Double Layers ◽

Fine Aggregate ◽

Binder Ratio ◽

Naoh Solution ◽

Concrete Target

The purpose of this experimental research is to study the flexural behavior of Ferro-Geopolymer slab panels. Initially the ratio of binder to fine aggregate (1:2, 1:2.5, 1:3) and the ratio of Na2SiO3/ NaOH solution (2.5) is considered. The different combination of Fly ash and GGBS were considered. Ratio of alkaline liquid to binder ratio is fixed as 0.45. The Geopolymer mortar mix that gives compressive strength nearly equal to M20 grade concrete target mean strength was used to cast Ferro-Geopolymer slab panels. A slab of size (1000X1000X30) mm were cast of both ferrocement and Ferro-Geopolymer slab panels with two types of mesh were used such as square woven and square welded with single and double layers. Based on the results of slab load vs deflection of both types of meshes were compared from the characteristics of such as first crack load and ultimate load.

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THE INFLUENCE OF INITIAL MATERIALS ON THE COMPRESSIVE STRENGTH OF GEOPOLYMER SOILS

Proceedings of International Structural Engineering and Construction ◽

10.14455/isec.res.2014.30 ◽

2014 ◽

Vol 1 (1) ◽

Author(s):

Hong Chan Nguyen ◽

Anh Tuan Nguyen ◽

Namshik Ahn

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Sodium Silicate ◽

Alkaline Solution ◽

Building Materials ◽

Clay Content ◽

Carbon Dioxide Production ◽

Environmental Benefits ◽

Curing Temperature ◽

Low Carbon

In recent years, geopolymers have received significant attention because they show environmental benefits, such as a reduction in the consumption of natural resources and a decrease in the net production of CO2. In addition, as green material, soil has low carbon dioxide production emissions compared to other building materials. In this research, soil was combined with activator alkaline to produce hardening materials as geopolymer soils. An alkaline solution with sodium hydroxide, sodium silicate and fly ash was used. The influence of clay content on the geopolymer soils’ compressive strength was investigated. The best strengths were obtained from 5% to 12% clay content. SEM photos were also taken from specimens to investigate the structure of geopolymer soils. When combined with soil and fly ash in geopolymerization, fly ash reacted to the alkali solution quickly. The relationships between many variables such as clay content, fly ash, alkaline solution, curing time, and curing temperature were investigated by using a statistical analysis program with over 100 initial parameters. These results also indicate that the use of soils in geopolymer soil should have been limited. Additionally, increasing the sodium silicate in the alkaline liquid affected the geopolymerization reaction significantly. However, the suitable Si on the alkaline solution and soil should be limited.

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