Development of Geopolymer Utilizing Inorganic Waste Materials

2014 ◽  
Vol 896 ◽  
pp. 553-556 ◽  
Author(s):  
Tjokorde Walmiki Samadhi ◽  
Pambudi Pajar Pratama ◽  
Nurhidayati Muan
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Setting Time ◽  
Factorial Experiment ◽  
Curing Temperature ◽  
Engineering Properties ◽  
Waste Materials ◽  
Setting Times ◽  
Wide Range ◽  
Inorganic Waste

Geopolymers, which are produced by the reaction between aluminosilicate solid precursors and concentrated alkali solutions, is an environmentally attractive construction material due to its much smaller carbon footprint compared to ordinary Portland cement (OPC), and its ability to consume a wide range of solid inorganic waste materials. This work describes the synthesis of geopolymers utilizing local aluminosilicate materials and the evaluation of several key engineering properties of the geopolymer product as a construction cement. A simple 22factorial experiment is undertaken to measure the effect of types aluminosilicate solids (metakaolin produced by calcining a Belitung kaolin at 750 °C, and coal fly ash from an East Java baseload powerplant) and alkali activators (NaOH and KOH solutions) on the initial and final setting time of the geopolymer cement mortar. All geopolymer mortar samples exhibit longer setting times compared to OPC mortars. Statistical analysis indicates that KOH produces faster initial setting than NaOH, while fly ash produces faster setting times compared to metakaolin. A 23factorial experiment is conducted subsequently, adding curing temperature (60 and 80 °C) to the experimental factors. The key engineering property measured in the second experiment is the compressive strength of geopolymer mortars. ANOVA treatment of the measured data indicates that all three experimental factors significantly impacts the compressive strength. Consistent with the preceding experiment, the use of fly ash and KOH significantly increases the strength of the geopolymer mortar. Higher curing temperature is also found to increase the strength. The use of metakaolin as geopolymer precursor produces compressive strength approximately 50% than that of the OPC mortar, while fly ash produces a geopolymer mortar strength that is at least as good as OPC.

scholarly journals Effect of Copolymer Latexes on Physicomechanical Properties of Mortar Containing High Volume Fly Ash as a Replacement Material of Cement

2014 ◽  
Vol 2014 ◽  
pp. 1-11
Author(s):  
El-Sayed Negim ◽  
Latipa Kozhamzharova ◽  
Yeligbayeva Gulzhakhan ◽  
Jamal Khatib ◽  
Lyazzat Bekbayeva ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Compressive Strength ◽  
Fly Ash ◽  
Setting Time ◽  
High Volume ◽  
Physicomechanical Properties ◽  
Partial Replacement ◽  
Setting Times ◽  
High Volume Fly Ash ◽  
Scanning Electron

This paper investigates the physicomechanical properties of mortar containing high volume of fly ash (FA) as partial replacement of cement in presence of copolymer latexes. Portland cement (PC) was partially replaced with 0, 10, 20, 30 50, and 60% FA. Copolymer latexes were used based on 2-hydroxyethyl acrylate (2-HEA) and 2-hydroxymethylacrylate (2-HEMA). Testing included workability, setting time, absorption, chemically combined water content, compressive strength, and scanning electron microscopy (SEM). The addition of FA to mortar as replacement of PC affected the physicomechanical properties of mortar. As the content of FA in the concrete increased, the setting times (initial and final) were elongated. The results obtained at 28 days of curing indicate that the maximum properties of mortar occur at around 30% FA. Beyond 30% FA the properties of mortar reduce and at 60% FA the properties of mortar are lower than those of the reference mortar without FA. However, the addition of polymer latexes into mortar containing FA improved most of the physicomechanical properties of mortar at all curing times. Compressive strength, combined water, and workability of mortar containing FA premixed with latexes are higher than those of mortar containing FA without latexes.

Interrelationship Analysis of Geopolymer Components Using Pearson Correlation Technique

2014 ◽  
Vol 567 ◽  
pp. 417-421 ◽  
Author(s):  
Andri Kusbiantoro ◽  
Norbaizurah Rahman ◽  
Noor Fifinatasha Shahedan
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Elemental Composition ◽  
Setting Time ◽  
Source Material ◽  
Curing Temperature ◽  
Strength Development ◽  
Correlation Technique ◽  
High Calcium ◽  
Geopolymer Binder

Performance of geopolymer based specimens is significantly affected by internal and external aspects. Curing temperature and air humidity are among the prominent external factors that contribute to the alteration of geopolymer properties. Nevertheless, internal component of geopolymer binder also carries essential effect to the hardened geopolymer binder produced. In this research, the study was concentrated on the elemental composition of source material components and their interrelation to the performance of geopolymer binder produced. Different types of fly ash were used as the source material in this research. Low calcium (class-F) fly ash was combined with high calcium (class-C) fly ash to determine the elemental composition effect, particularly SiO2, Al2O3, and CaO to the geopolymer properties. Analysis using SYSTAT statistical software indicated the importance of oxide composition of source material to the geopolymer specimens produced. Initial setting time of geopolymer paste was also possibly important to the compressive strength of geopolymer specimens produced. Nevertheless, final setting time indicated less importance to the compressive strength development of geopolymer binder.

scholarly journals Predictive Model of Setting Times and Compressive Strengths for Low-Alkali, Ambient-Cured, Fly Ash/Slag-Based Geopolymers

Minerals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 920 ◽  
Author(s):  
Supphatuch Ukritnukun ◽  
Pramod Koshy ◽  
Aditya Rawal ◽  
Arnaud Castel ◽  
Charles Christopher Sorrell
Keyword(s):  
Blast Furnace ◽  
Fly Ash ◽  
Blast Furnace Slag ◽  
Setting Time ◽  
Curing Temperature ◽  
Setting Times ◽  
Optimal Mix ◽  
High Alkalinity ◽  
Class F Fly Ash ◽  
Furnace Slag

The effects of curing temperature, blast furnace slag content, and Ms on the initial and final setting times, and compressive strengths of geopolymer paste and mortars are examined. The present work demonstrates that ambient-cured geopolymer pastes and mortars can be fabricated without requiring high alkalinity activators or thermal curing, provided that the ratios of Class F fly ash (40–90 wt%), blast furnace slag (10–60 wt%), and low alkalinity sodium silicate (Ms = 1.5, 1.7, 2.0) are appropriately balanced. Eighteen mix designs were assessed against the criteria for setting time and compressive strength according to ASTM C150 and AS 3972. Using these data, flexible and reproducible mix designs in terms of the fly ash/slag ratio and Ms were mapped and categorised. The optimal mix designs are 30–40 wt% slag with silicate modulus (Ms) = 1.5–1.7. These data were used to generate predictive models for initial and final setting times and for ultimate curing times and ultimate compressive strengths. These projected data indicate that compressive strengths >100 MPa can be achieved after ambient curing for >56 days of mixes of ≥40 wt% slag.

scholarly journals Investigation on the Compressive Strength and Time of Setting of Low-Calcium Fly Ash Geopolymer Paste Using Response Surface Methodology

Polymers ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 3461
Author(s):  
Pauline Rose J. Quiatchon ◽  
Ithan Jessemar Rebato Dollente ◽  
Anabel Balderama Abulencia ◽  
Roneh Glenn De Guzman Libre ◽  
Ma. Beatrice Diño Villoria ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Unconfined Compressive Strength ◽  
Setting Time ◽  
Initial Setting Time ◽  
Alkali Activator ◽  
Setting Times ◽  
Confirmatory Tests ◽  
Initial Setting

Approximately 2.78 Mt of coal fly ash is produced in the Philippines, with a low utilization rate. Using fly ash-based geopolymer for construction will lessen the load sent to landfills and will result in lower GHG emissions compared to OPC. It is necessary to characterize the fly ash and optimize the geopolymer components to determine if it can replace OPC for in situ applications. The activator-to-precursor ratio, the water-to-solids ratio, and the sodium hydroxide-to-sodium silicate ratio were optimized using a randomized I-optimal design from the experimental results of 21 runs with five replicates, for a total of 105 specimens of 50 mm × 50 mm × 50 mm paste cubes. The engineering properties chosen as the optimization responses were the unconfined compressive strength (UCS), the initial setting time, and the final setting time. The samples were also ambient-cured with the outdoor temperature ranging from 30 °C to 35 °C and relative humidity of 50% ± 10% to simulate the on-site environment. Runs with high unconfined compressive strength (UCS) and short setting times were observed to have a low water-to-solids (W/S) ratio. All runs with a UCS greater than 20 MPa had a W/S ratio of 0.2, and the runs with the lowest UCS had a W/S of 0.4. The initial setting time for design mixes with a W/S ratio of 0.2 ranged from 8 to 105 min. Meanwhile, five out of seven design mixes with a W/S ratio of 0.4 took longer than 1440 min to set. Specimens with an alkali activator ratio (NaOH/WG) of 0.5 (1:2) and 0.4 (1:2.5) also had significantly lower setting times than those with an alkali activator ratio of 1. The RSM model was verified through confirmatory tests. The results of the confirmatory tests are agreeable, with deviations from the expected UCS ranging from 0 to 38.12%. The generated model is a reliable reference to estimate the UCS and setting time of low-calcium FA geopolymer paste for in situ applications.

Advancements in Properties of Cements Containing Pulverised Fly Ash and Nanomaterials by Blending and Ultrasonication Method (Review- Part II)

2019 ◽  
Vol 24 ◽  
pp. 37-44 ◽  
Author(s):  
Mehmet Serkan Kirgiz
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Flexural Strength ◽  
Review Paper ◽  
Setting Time ◽  
Heat Of Hydration ◽  
Strength Gain ◽  
Hydration Properties ◽  
Setting Times ◽  
Current Article

The second part of this review paper will explain Hydration properties of Portland pulverised fly ash cement section, Effect of nanomaterial on setting–time section, Effect of nanomaterial on heat of hydration section, Strength gain mechanisms for hardened Portland pulverised fly ash cement paste and mortar section, Effect of nanomaterial on compressive strength section, Effect of nanomaterial on flexural strength (Bending) section, and Conclusion section. Experiments reported include the setting–times, the heat of hydration, the compressive strength gain, and the flexural strength gain in the current article. According to the result, nanoparticles, especially the GNP, increase the heat of hydration of cement, and accelerate the time of setting evidently, both initial and final setting-time. The most effective nanoparticle on early compressive strength gain and flexural strength gain is the GNP. The article also points the effects of the nanoparticles on the strength gain of cement comprehensively. Consequently, the prominent cement technology can use the nanoparticles dispersed in liquid by ultrasonication method to increase the properties of cement based materials effectively.

Engineering Properties of Controlled Low-Strength Material Made with Residual Soil and Class F Fly Ash

2014 ◽  
Vol 597 ◽  
pp. 345-348 ◽  
Author(s):  
Yeong Nain Sheen ◽  
Li Jeng Huang ◽  
Duc Hien Le
Keyword(s):  
Compressive Strength ◽  
Elastic Modulus ◽  
Fly Ash ◽  
Setting Time ◽  
Engineering Properties ◽  
Residual Soil ◽  
Strength Material ◽  
Low Strength ◽  
Controlled Low Strength Material ◽  
Class F Fly Ash

This paper aims to employ combination of residual soil and Class F fly ash in developing a controlled low-strength material (CLSM), primarily used as backfilling material. In the mixture, surplus soil and concrete sand was blended well together with a given proportion of 6:4 by volume. Three levels of binder content (i.e. 80-, 100-and 130 kg/m3) and different percentages fly ash (i.e., 0%, 15%, 30%, and 45%) substituting to Portland cement were previously chosen for mix design. Several major engineering properties of the CLSM such as fresh density, flowability, setting time, water bleeding, unconfined compressive strength, and elastic modulus were investigated via a laboratory study. Testing results indicate that most of the proposed CLSM mixtures satisfy the requirements of excavatability as the 28-days compressive strength ranges from 0.3 to 1.4 MPa. In addition, increase in FA substituting to OPC resulted in workability improvement, setting time extension as well as compressive strength and elastic modulus reduction.

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 The Effect of Calcium Formate, Sodium Sulfate, and Cement Clinker on Engineering Properties of Fly Ash-Based Cemented Tailings Backfill

2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Wenbin Xu ◽  
Qianlong Li ◽  
Sada Haruna
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Sodium Sulfate ◽  
Setting Time ◽  
Practical Interest ◽  
Engineering Properties ◽  
Cement Clinker ◽  
Strength Development ◽  
Water Rate ◽  
Calcium Formate

The influence of admixtures on the engineering properties of fly ash-based cemented tailings backfill (CTB) is a topic of significant practical interest, as it affects the backfilling cost and the environmental effect of mining operation. This paper presents results of an experimental study on the influence of different activators on the engineering properties of the CTB containing fly ash. CTB samples are mixed with different contents of calcium formate, sodium sulfate, and cement clinker (4%, 8%, and 12% by mass of total binder) and cured in a cubic chamber (at 20°C and RH 90 ± 5%) for 3, 7, and 28 days. Specimen tests were performed to assess the slump height, setting time, leaching water rate, vertical settlement, and strength development. Furthermore, the XRD analyses were conducted on the hydration products of fly ash-based CTB mixtures. The results show that activators can cause decrease in the slump height, leaching water rate, and vertical settlement of fly ash-based CTB mixtures. However, inclusion of cement clinker ranging from 8%–12% of total binder can reduce the slump height, setting time, leaching water rate, and vertical settlement to an acceptable range. Addition of calcium formate in the fly ash-based CTB caused negligible change in compressive strength. The compressive strength improved with higher content of sodium sulfate and cement clinker at the age of 28 days. XRD analyses showed considerable intensity counts of C-S-H gel, calcium hydroxide, and ettringite, resulting from the addition of sodium sulfate and cement clinker. This study also shows that an understanding of the effect of activators on the engineering properties of fly ash-based CTB is crucial for designing a cost-effective and workable CTB with reduced environmental impact.

scholarly journals The Effect of Using Linear Low Density Polyethylene (LLDPE) Powder and Rice Husk Asn on Compressive Strength and Intital Setting Time of Alkaline-Activated Mortar

2021 ◽  
Vol 921 (1) ◽  
pp. 012070
Author(s):  
M Sofyan ◽  
A O Irlan ◽  
A Rokhman ◽  
D D Purnama ◽  
R R R Utami
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Rice Husk ◽  
Rice Husk Ash ◽  
Setting Time ◽  
Strength Test ◽  
Curing Temperature ◽  
Test Results ◽  
The Core ◽  
Compressive Strength Test

Abstract Fly Ash, Rice Husk Ash and Linear Low Density Polyethylene (LLDPE) Plastic Waste also contribute to environmental problems. Starting from the problem of CO2 emissions to ecosystem damage due to the accumulation of waste on the earth’s surface. Therefore, this study focuses on the use of Fly Ash, Rice husk ash and LLDPE Powder as a mixture of Alkaline-Activated Mortar. In this study, Fly Ash as a Pozzolanic Material mixed with Alkaline Activator Solution serves as a binder for Mortar. Rice husk ash is used as a substitute material for Fly ash while LLDPE powder functions as a substitute material for sand. The percentage of LLDPE powder used in the mortar mixture is from 0 to 15% of the total weight of the mixture. While the percentage of rice husk ash used in the mixture is 7%, Alkali Activator Solution 27% and Sand ranging from 24.5 to 39.5%. There are six variations of the mortar specimen (AAMP1, AAMP2, AAMP3, AAMP4, AAMP5, AAMP6). Initial setting time testing is done on binder mortar. The mortar compressive strength test was carried out at the age of 7 days after curing the oven at temperatures of 40°C and 60°C. From the test results obtained the highest compressive strength of 11.3 MPa on the AAMP6 test object with a curing temperature of 60°C where the percentage of LLDPE powder on the specimen is 15%. The core of the longest setting time is in the AAMP6 Alkaline-Activated Mortar binder variation, which is 180 minutes. The mortar compressive strength test was carried out at the age of 7 days after curing the oven at temperatures of 40°C and 60°C. From the test results obtained the highest compressive strength of 11.3 MPa on the AAMP6 test object with a curing temperature of 60°C where the percentage of LLDPE powder on the specimen is 15%. The core of the longest setting time is in the AAMP6 Alkaline-Activated Mortar binder variation, which is 180 minutes. The mortar compressive strength test was carried out at the age of 7 days after curing the oven at temperatures of 40°C and 60°C. From the test results obtained the highest compressive strength of 11.3 MPa on the AAMP6 test object with a curing temperature of 60°C where the percentage of LLDPE powder on the specimen is 15%. The core of the longest setting time is in the AAMP6 Alkaline-Activated Mortar binder variation, which is 180 minutes.

scholarly journals Effect of Calcium Nitrate on the Properties of Portland–Limestone Cement-Based Concrete Cured at Low Temperature

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1611
Author(s):  
Gintautas Skripkiūnas ◽  
Asta Kičaitė ◽  
Harald Justnes ◽  
Ina Pundienė
Keyword(s):  
Compressive Strength ◽  
Cement Paste ◽  
Setting Time ◽  
Calcium Nitrate ◽  
Curing Temperature ◽  
Hardened Concrete ◽  
Cement Pastes ◽  
Initial Setting Time ◽  
Initial Setting ◽  
Early Strength

The effect of calcium nitrate (CN) dosages from 0 to 3% (of cement mass) on the properties of fresh cement paste rheology and hardening processes and on the strength of hardened concrete with two types of limestone-blended composite cements (CEM II A-LL 42.5 R and 42.5 N) at different initial (two-day) curing temperatures (−10 °C to +20 °C) is presented. The rheology results showed that a CN dosage up to 1.5% works as a plasticizing admixture, while higher amounts demonstrate the effect of increasing viscosity. At higher CN content, the viscosity growth in normal early strength (N type) cement pastes is much slower than in high early strength (R type) cement pastes. For both cement-type pastes, shortening the initial and final setting times is more effective when using 3% at +5 °C and 0 °C. At these temperatures, the use of 3% CN reduces the initial setting time for high early strength paste by 7.4 and 5.4 times and for normal early strength cement paste by 3.5 and 3.4 times when compared to a CN-free cement paste. The most efficient use of CN is achieved at −5 °C for compressive strength enlargement; a 1% CN dosage ensures the compressive strength of samples at a −5 °C initial curing temperature, with high early strength cement exceeding 3.5 MPa but being less than the required 3.5 MPa in samples with normal early strength cement.

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