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A comprehensive summary of the extensive studies conducted on fly ash-based geopolymer concrete is presented. Test data are used to identify the effects of salient factors that influence the properties of the geopolymer concrete in the fresh and hardened states. These results are utilized to propose a simple method for the design of geopolymer conc...
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... In this aspect, geopolymer technology can be used in the concrete as the alternative of OPC. An alkaline activator is required to react with the silica and aluminum in the source material because of this a chemical reaction takes place which is called as polymerization process and "geopolymer" is termed for this kind of binders [2], [3]. These geopolymer concretes are needed where environmental conditions are not suitable for OPC concrete. ...
... Lot of research works have been carried out for several years to conform geopolymer concrete as best construction material [2], [3], [5], [6], [7], [8]. There is a need of alternative concrete like geopolymer concrete, where large scale of wastes were disposed from the industries [1]. ...
As CO2 emissions are increasing in the atmosphere and causes global warming with the production of cement, the alternative pozzolanic material is needed. The alternative pozzolanic material for cement in the production of concrete is GGBS. Geopolymer Concrete (GPC) is an alternative material for conventional concrete. Geopolymer concrete is made by mixing GGBS, fine aggregate, coarse aggregate and alkaline activator solution. GGBS is a by-product of the iron industry. This paper shows the results on experimental investigation done on reinforced geopolymer concrete beams to know the flexural behavior. The alkaline activator solution is prepared by sodium hydroxide NaOH and sodium silicate Na2SiO3 in 1:2.5 ratio. The flexural behavior of the beams is examined with different molars of NaOH solution. The GPC beams are compared with conventional reinforced concrete beam of M40 grade concrete. The type of curing adopted in the experimental study is ambient. The size of beam is 1000 mm × 150 mm × 150 mm. The flexural test is done on the loading frame of capacity 200 tons. The ultimate load, cracking load and the maximum deflection and the crack pattern is determined and the load Vs deflection graphs are plotted. This experimental study gives a clear conclusion on the flexural behavior of conventional reinforced concrete beam and reinforced geopolymer concrete beam made with GGBS.
... Geopolymer concrete is made by fly ash, GGBS with alkali activation and special concrete is prepared [2], [3] The energy required for the manufacture of cement based concrete is very large than the energy required for the manufacture of geopolymer cement, this is effecting the environment [3].Where the normal concrete i.e. ordinary Portland cement concrete (OPCC) is not suitable at that conditions special concrete with good durability aspect is preferred, such alternative concrete like geopolymer concrete is in needed. ...
... Geopolymer concrete is made by fly ash, GGBS with alkali activation and special concrete is prepared [2], [3] The energy required for the manufacture of cement based concrete is very large than the energy required for the manufacture of geopolymer cement, this is effecting the environment [3].Where the normal concrete i.e. ordinary Portland cement concrete (OPCC) is not suitable at that conditions special concrete with good durability aspect is preferred, such alternative concrete like geopolymer concrete is in needed. ...
... Where research works were carried out from several years to conform geopolymer concrete is a good material for construction purpose. In India like country alternative concrete like geopolymer concrete have a great acceptance realizing the geopolymer concept CSIR-structural engineering research Centre carried research on different parameters of geopolymer concrete for more than a decade [1,2,3,4]. Mainly for chemical resistant structures the geopolyemer concrete is used and it is increasing slowly. In some countries like Australia and Spain had done considerable amount of research, these research have proposed some suitable materials for the preparation of geopolymer concrete and also mix design and durability aspects [11,12,13]. ...
Concrete is the most popular material used in the construction works in which cement is the main composite. The manufacturing of cement involves the emission of greenhouse gases into the atmosphere which are responsible for global warming. Hence the researches are currently focused on various materials to replace and reducing the usage of cement. In this study Geopolymer concrete is prepared with Ground Granulated Blast furnace Slag (GGBS) with the addition of steel fibers. GGBS is the by-product produced from steel industry. Steel fibers are added to increase the tensile strength of concrete. In this experimental investigation geopolymer concrete containing GGBS and steel fiber (0.5%) with 8 Molar and 10 Molar alkaline activators are used. The ratio of these alkali activators is 1:2.5. The results showed that fiber can significantly enhance the Mechanical properties. The enhancement also increases with the increasing fiber volume fraction.
... Geopolymers, introduced by Joseph Davidovits (Habert et al. 2011), are inorganic alumino-silicate materials obtained by activation at room temperature of a low-calcium alumino-silicate source by an alkali hydroxide solution (Saliha 2017). In the last decades, they have become the subject of great interest for researchers due to their good mechanical properties and low CO 2 emission rate (Rangan 2010). Several recent studies have shown that geopolymeric binders can be synthesised by alkaline activation of aluminosilicates obtained from industrial wastes such as fly ash (Djobo et al. 2014), metakaolins resulting from the calcination of clay between 550 and 750°C (Sontia et al. 2021;Sontia et al. 2022;Rahier et al. 1996;Elimbi, Tchakoute, and Njopwouo 2011). ...
... This mixture was made at a liquid/solid ratio of 0.75. The total mass of aggregates (sand + 5/15 gravel) to be added was defined as 80% of the geopolymer mass according to the standards for geopolymer concrete (Rangan 2010). After mixing the geopolymer for 5 minutes, 620g of aggregates were introduced into the geopolymer and the mixture was synthesised again in the mixer for 5 minutes. ...
The ever-increasing cost of cement and its production of harmful carbone dioxide (CO 2) has led development actors to continuously search for less environmentally polluting and low-cost binders. Hence the interest in the valorisation of agricultural resources through the production of different binders such as silicate for the elaboration of geopolymers at low manufacturing temperatures (<100 °C). In this study, Ingessil industrial silicate and rice husk ash silicate were used as pozzolan raw materials to prepare geopolymers with sodium hydroxide as activator at a concentration of 12 M. Two types of samples were developed: geopolymer mortars based on Ingessil silicate and geopolymer concretes based on Ingessil industrial silicate and rice husk ash silicate. Sand and gravel were used as fine and coarse aggregates for the production of geopolymer concretes. They were represented 80% of the mass of the geopolymer concretes according to the standards of elaboration.The porosity values obtained were of the order of 30%, i.e. water absorption values of about 18%, apparent specific weight of about 5% and bulk density of 1.7%. The mechanical values of BGAC-RHA samples are higher than those of BGAC-I. The physico-chemical properties of geopolymer mortars and concretes were similar. cementitious composite materials based on calcined clay activated by silicate from rice husk ash and Ingessil silicate-activator: sodium hydroxide (NaOH).
... This result was supported by the researcher [46] and states that strength development of GPC (GPC) is faster than ordinary Portland cement concrete (OPC). Both the GPC and OPC have a similar effect on the water-binder ratio; an increase in the water-FA ratio tends to decrease the compressive strength of GPC [47]. Water content in the mix is the sum of water present in the activator solution and extra water. ...
... Relation between compressive strength and water-geopolymer solids ratio under elevated temperature curing[47]. ...
Geo-polymer concrete (GPC) can be obtained by chemical reactions in industrial products and naturally available alumino silicate sources. The main drawback of GPC is that there are no standard or specific guidelines for mix production. Even though the lack of a proper mix design method limits the geo-polymer acceptance in the industry. In the case of cement concrete, the only variable parameter is the water-cement ratio, which strongly influences the concrete's mechanical properties and durability. For GPC, numerous factors such as alkaline liquid to cementitious material ratio, alkaline activator ratio, binder type, curing type, etc., directly and indirectly, influence the fresh, hardened, and microstructural properties of the concrete. This paper presents an overview of the chemistry behind the geopolymer concrete, alumino-silicate source, and the microstructural analysis of binders under different curing conditions.
... Geopolymer binders are acid-resistant, unaffected by alkalinity or high temperatures, and quickly gain strength. When compared to cement, geopolymer reduces shrinkage greatly [13,14]. The SEM and EDAX analyses con rmed that the curing time and temperatures play a vital role in the specimen's strength in the form of better bonding between the slag and soil particles. ...
This study aims to evaluate the role of steel slag and GGBFS in mud-based geopolymer blocks. For all mixes, a constant proportion of 30% GGBFS is used. Steel slag is replaced with soil in increments of 5%, ranging from 0–30%. The specimens were tested for dry and wet compressive strengths, water absorption, Ultrasonic Pulse Velocity (UPV), Spray erosion, efflorescence, and dimensionality.
Scanning Electron Microscopic Images were used to examine the microstructure of the specimens (SEM). The optimal mix was discovered to be 20% steel slag, 30% GGBFS, and 50% soil (i.e., Mix SGSS20). Under both curing conditions, the optimal amount of slags improved the strength behaviour of mud-based geopolymer masonry blocks. The experimental and microstructural results confirmed that the SGSS20 mix had better results due to good geopolymer formation in its interior composition. more significant dissolution of silica and alumina particles present in the slags improved the density of the blocks and reduced the pores.
... This may be explained by the water content of the Mk-GPC specimens leaking out during oven drying. This supports Rangan's [61] assertions that water is released during the formation of geopolymer (that is, during curing and the further drying period of the matrix), leaving behind nano-pores. Albidah et al. [62] also reported a similar trend, showing that the water absorption percentage increases in metakaolin-based geopolymer concrete, varying consistently between 4.6% and 7% when compared with cement concrete mixes. ...
Cement production is one of the most important industries on the planet, and humans have relied on is use dating back to the dawn of civilization. Cement manufacturing has increased at an exponential rate, reaching 3 billion metric tons in 2015, representing a 6.3% annual growth rate and accounting for around 5–8% of global carbon dioxide (CO2) emissions. Geopolymer materials, which are inorganic polymers made from a wide range of aluminosilicate powders, such as metakaolin, fly ash, and blast furnace or steel slags, have also been elicited for use due to concerns about the high energy consumption and CO2 emissions connected with cement and concrete manufacturing. This study focused on the mechanical and durability properties of metakaolin in concrete production. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) analyses were used to confirm the characteristics of kaolin and metakaolin. The results showed that 15 wt.% metakaolin can be used to partially replace cement, and that metakaolin, when synthesized with alkaline activators, can also be utilized as a geopolymer to totally replace cement in concrete production. For predicting the compressive strength of different concrete mixtures, few practical models have been presented. This research has shed light on the possibility of utilizing ecologically friendly materials in the building, construction, and transportation sectors to decrease carbon dioxide emissions.
... Rangan [35] guidelines based on the trial-and-error method were adopted for calculating the mix design of TGPC of grade M55. The proportions of fly ash, GGBS, and RHA, the molarity of NaOH, and the alkaline liquid-to-binder ratio were adopted from the detailed study carried out by the authors, the result of which are presented elsewhere [30]. ...
Sustainable development is a major issue confronting society today. Cement, a major
constituent of concrete, is a key component of any infrastructure development. The major drawback
of cement production is that it involves the emission of CO2, the predominant greenhouse gas causing
global warming. The development of geopolymers has resulted in a decrease in cement production,
as well as a reduction in CO2 emissions. During mass concrete production in the construction of very
large structures, interfaces/joints are formed, which are potential failure sites of crack formation.
Concrete may interface with other concrete of different strengths, or other construction materials,
such as steel. To ensure the monolithic behavior of composite concrete structures, bond strength at
the interface should be established. The monolithic behavior can be ensured by the usage of shear
ties across the interface. However, an increase in the number of shear ties at the interface may reduce
the construction efficiency. The present study aims to determine the interfacial shear strength of
geopolymer concrete as a substrate, and high-strength concrete as an overlay, by adding 0.50%, 0.75%,
and 1% crimped steel fibers, and two and three shear ties, at the interface of push-off specimens. It
was found that three shear ties at the interface can be replaced by two shear ties and 0.75% crimped
steel fibers. In addition, a method was proposed to predict the interface shear strength of the concrete
composite, which was found to be comparable to the test results.
... The greater the water absorption, the more water is required to produce workable concrete. According to Rangan (2010), the molar concentration of sodium hydroxide has a significant effect on the workability of GPCs. As a result, all slump values were within the ACI 211.1 (1991) range for various constructions. ...
Research into substituting recycled materials for cement and aggregates can yield beneficial natural resource conservation, waste management, cost savings, and reduced embodied energy in concrete. Hence, this research investigates the potential adoption of coal fly ash (CFA) and rice husk ash (RHA) as geopolymer binders to partially substitute cement in varying proportions up to 25%. However, cupola furnace slag (CFS) was also used as a partial substitute of crushed granite from 0% to 35% in steps of 5% in the production of geopolymer concrete (GPC). The selected geopolymer binders were synthesized using an alkaline solution. Workability, compressive strength, and rapid chloride penetration tests on fresh and hardened normal concrete (NC) as control and GPC containing CFS were evaluated at different water-binder ratios. The findings revealed that integrating 15%CFA, 20%RHA, and 30%CFS with w/b of 0.50 and 0.65 improved the workability by 180% and 105.7%, respectively, but compressive strength is significantly reduced. The findings further showed that combining 75%OPC, 20%CFA, 5%RHA, 100%RS, 20%CFS, and 80%CG results in optimal compressive strength of 19.68 N/mm2 and, 21.49 N/mm2 at 28 days and 56 days with w/b of 0.50, respectively, as contrasted to the lowest possible strength requirement. The Rapid Migration Test (RMT) was used to determine the chloride ions permeability in various concrete mixes. The results show that GPC produced with the combination of 15%CFA, 20%RHA 65%OPC, 30%CFS, and 70%CG with w/b of 0.65 is more durable and has higher chloride ion penetration resistance than most other mix proportions.
... There is high growth in the demand for new construction materials that are green and produce a low level of greenhouse gas emissions during their manufacture. This makes geopolymer concrete a good and potentially ideal alternative to Portland cement concrete [1]. These concretes are produced through the alkali activation of industrial alumino-silicate waste such as ashes and slags; moreover, they are considered ecofriendly materials as they have low greenhouse gas emissions in comparison with traditional cement material [2]. ...
... The geopolymerization procedure relies upon numerous parameters, such as the chemical and mineralogical composition of the primary materials, curing treatment temperature, water content, and concentration of the alkaline solution [3]. Low-calcium fly ash-based geopolymer has several advantages over Portland cement concrete: almost no drying shrinkage, very good sulfate attack resistance, low creep, and great corrosive resistance [1]. ...
... For the M55 grade TGPC, Rangan's standards [59] were followed to determine the ingredients for the mixture proportions. Trial and error led to the current mix ratio, given that there is currently no standard way to create GPCs. ...
Beam–column joints are extremely vulnerable to lateral and vertical loads in reinforced
concrete (RC) structures. This insufficiency in joint performance can lead to the failure of the whole
structure in the event of unforeseen seismic and wind loads. This experimental work was conducted
to study the behaviour of ternary blend geopolymer concrete (TGPC) beam-column joints with the
addition of hybrid fibres, viz., steel and polypropylene fibres, under reverse cyclic loads. Nine RC
beam-column joints were prepared and tested under reverse cyclic loading to recreate the conditions
during an earthquake. M55 grade TGPC was designed and used in this present study. The primary
parameters studied in this experimental investigation were the volume fractions of steel fibres (0.5%
and 1.0%) and polypropylene fibres, viz., 0.1 to 0.25%, with an increment of 0.05%. In this study,
the properties of hybrid fibre-reinforced ternary blend geopolymer concrete (HTGPC) beam-column
joints, such as their ductility, energy absorption capacity, initial crack load and peak load carrying
capacity, were investigated. The test results imply that the hybridisation of fibres effectively enhances
the joint performance of TGPC. Also, an effort was made to compare the shear strength of HTGPC
beam-column connections with existing equations from the literature. As the available models did
not match the actual test results, a method was performed to obtain the shear strength of HTGPC
beam-column connections. The developed equation was found to compare convincingly with the
experimental test results.