fly ash pastes mechanical

(PDF) Influence of calcium compounds on the mechanical ...

The influence of calcium compounds (CaO and Ca(OH)(2)) on the mechanical properties of fly ash based geopolymers has been studied. Calcium compounds were substituted in fly ash at 1, 2 and 3 wt ...

The Effect of Mechano-Chemical Activation of Fly Ash ...

activated fly ash was tested and compared with reference. The overall objective of reported study was to develop a new binding material concept based on mechano-chemical activation (MCA) of fly ash with the use of nanoparticles and effective application of developed binders in self-consolidating concrete (SCC).

Mechanical Properties and Microstructure of Class C Fly ...

For paste samples, water-to-fly ash ratio from 0.30 to 0.35 may meet the demand of workability as cement materials in construction application. For fly ash-based geopolymer, achieving the target fluidity required less water than needed for Portland cement paste. It was also common sense that more extra water resulted in better fluidity.

Mechanical Transformation of Fly Ash toward Its ...

Fly ash (FA) showed low reactivity when being used to prepare the binder for cemented paste backfill (CPB). In the present work, wet-grinding treatment was used to increase the pozzolanic reactivity of FA and promote its sustainable utilization. The results showed that wet-grinding could be a suitable and efficient technology for FA pretreatment.

The Influence of High Temperatures and Time on the ...

The paper deals with the use of fly ash in cement and concrete. Fly ash, primarily waste material, can be used as a binder because of pozzolanic properties. This fact positively influences the economic and ecological part of the construction. At present, also in the context of higher fire protection requirements fly ash, it is mentioned as a possible material for the protection of structures ...

Mechanical Properties and Microstructure of Class C Fly ...

This paper presents workability, compressive strength and microstructure for geopolymer pastes and mortars made of class C fly ash at mass ratios of water-to-fly ash from 0.30 to 0.35. Fluidity was in the range of 145–173 mm for pastes and 131–136 mm for mortars. The highest strengths of paste ...

Investigation of hydration products of fly ash–slag pastes ...

Pastes with higher amount of CFBC fly ash exhibit more porous structure. 6. Compressive strength of tested samples increases in time along with increasing amount of fly ash in pastes and, in case of most of samples, in time of hydration. Compressive strength of pastes with the highest amount of fly ash decreases between 28 and 90 days of curing.

Fresh and Hardened Properties of Fly Ash–Slag Blended ...

Influence of calcium compounds on the mechanical properties of fly ash geopolymer pastes. Journal of Hazardous Materials, 167(1), 82–88. Article Google Scholar Temuujin, J., Williams, R. P., & Van Riessen, A. (2009b). Effect of mechanical activation of fly ash on the properties of geopolymer cured at ambient temperature.

Chemo-mechanical properties of alkali-activated slag/fly ...

Blends of slag and fly ash was used as the precursor and WM was used as the filling material. Pastes with 0 %, 10 %, 20 %, 30 %, 40 % and 50 % WM were prepared for the investigation.

Alkali activated fly ash: effect of admixtures on paste ...

The fly-ash pastes were made by mixing the fly ash with the activating solution—a "solution/ash" ratio of 0.4 and 0.8 g of admixture per 100 g fly ash. Tests were also run on control material without admixtures. Also, Portland cement pastes were used as a reference system ("water/cement" ratio = 0.4 and admixture proportion = 0 and 0.8).

Effect of PVA fiber on mechanical properties of fly ash ...

A tendency including fly ash (FA), blast furnace slag, bottom ash, of first increasing and then decreasing with the increase in metakaolin (MK), and so on [3,4]. FA-based geopolymer the PVA fiber content was observed in these properties.

(PDF) Properties of high calcium fly ash geopolymer pastes ...

SEM analysisThe SEM photos of FA and FA10PC geopolymer pastes are shown in Fig. 6. The FA paste contains a larger number of non-reacted and/or partially reacted fly ash particles embedded in a continuous matrix. For FA10PC paste, a less number of fly ash particles are observed, and the matrix appears denser than that of the FA paste.

(PDF) Rheology and Mechanical Properties of Fly Ash-Based ...

Fresh geopolymer paste is a solid–liquid suspension [9]. The geopolymer mix at an early stage of the reaction is a three-part composite, assuming that the air content is neglected. The first component is the aluminosilicate precursor in the form of a solid phase (e.g., GGBFS, fly ash and metakaolin) [10].

Rheology of Cement Pastes with Siliceous Fly Ash and the ...

The use of fly ash in cement composites adversely affects its mechanical properties during the first days of mixture curing. Modern technology, in the form of an admixture containing the hydrated calcium silicates, allows to accelerate the hardening and binding process of concrete. In this paper, studies on the influence of the admixture on properties of concretes with the ordinary Portland ...

Materials | Free Full-Text | Mechanical Properties ...

The aim of the present study is to investigate the potential of sea water as a feasible alternative to produce alkali-activated fly ash material. The alkali-activated fly ash binder was fabricated by employing conventional pure water, tap water, and sea water based alkali activating solution. The characteristics of alkali-activated materials were examined by employing compressive strength ...

Effect of high volume fly ash on mechanical properties of ...

This paper reports the effects of incorporating high volume fly ash in fiber reinforced concrete. Fly ash was mixed as a partial fine aggregate replacement of approximately one third of the fines volume. The fibers were polypropylene or steel fibers at a maximum proportion of 1% by volume of the concrete. The results showed that fiber reinforced concrete that included high fly ash volume ...

Influence of calcium compounds on the mechanical ...

Abstract. The influence of calcium compounds (CaO and Ca(OH)(2)) on the mechanical properties of fly ash based geopolymers has been studied. Calcium compounds were substituted in fly ash at 1, 2 and 3 wt%, respectively.

Mechanical properties and microstructure of magnesia–fly ...

(2019). Mechanical properties and microstructure of magnesia–fly ash pastes. Road Materials and Pavement Design: Vol. 20, No. 5, pp. 1243-1254.

Microstructure and mechanical properties of fly ash ...

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Mechanical Properties and Microstructure of Class C Fly ...

This study considers mechanical properties and microstructure of class C fly ash-based geopolymer paste and mortar. 2. Experimental Test 2.1. Materials Class C fly ash (CFA) used in this study was obtained from Harbin Acheng Suibao Thermoelectric Power Plant, China. Chemical composition of fly ash precursor is 48.2% SiO2, 18.4% Al2O3

Mechanical Properties and Microstructure of Class C Fly ...

Mechanical Transformation of Fly Ash toward Its ...

Chindaprasirt et al. studied the effect of different fineness of fly ash on pore structure and microstructure of fly ash cement pastes. They reported that the blended cement paste containing finer fly ash particles exhibited a denser matrix and resulted in higher compressive strength and …

Mechanical and microscopic properties of fly ash ...

Additionally, at 28 days of curing, for high-calcium fly ash phosphoric acid-based geopolymer activated with 60% PA and solution to power (S/P = 1), the highest compressive strength was about 22 MPa, but the maximum compressive strength of low-calcium FAPG paste activated by 60% PA was 11.48 MPa, which was far lower than that of high-calcium ...

THE EFFECT OF FLY ASH ON THE WORKABILITY AND MECHANICAL ...

Fly ash increases the paste volume leading to an increase oof plasticity and cohesion [54]. Moreover, fly ash particles pa due to their spherical nature tend to act as a lubricant to the aggregates interface reducing friction and in increasing workability of the concrete mixture. ... S. Yazici and H. S. Arel, "Effects of fly ash fineness on the ...

Frontiers | Mechanical-Chemical Activation of Coal Fly ...

Mechanical strength of alkali-activated paste prepared with ground or unground coal fly ash and cured for 20 h at 85°C. The starting ashes and reaction products were characterized by XRD, scanning electron microscopy (SEM/EDX) and NMR.

Microstructure and mechanical properties of fly ash ...

Abstract. Regarding the wide use of fly ash in normal and high-strength concrete, this study aims to investigate the microstructure and mechanical properties of fly ash blended cement pastes. To fulfill the aim of this study, multiple techniques, including scanning electron microscopy with backscattered electron and energy-dispersive X-ray ...

Physical and mechanical properties and micro ...

Furthermore, geopolymer paste incorporated with 0.1 wt.% functionalized MWCNTs and having 30 % substitution of fly ash with GBFS exhibits a higher compressive and flexural strength and a lower water absorption capacity compared with all other geopolymer pastes.

Insights into the microstructure evolution of slag, fly ...

Fig. 2 reveals the micromorphology of the blended pastes. Fly ash particles with spherical shapes are widely spread in the paste, and only a small fraction of fly ash particles have been reacted, as shown in Fig. 2a. The microstructure of C&S appears more compact and denser, as shown in Fig. 2b. The slag particles exhibit higher grey values and a more homogeneous nature than those of cement ...

Geopolymer pervious concrete modified with granulated ...

Geopolymer is green cementitious material that can be produced from industry waste or abundant earth materials through alkali-activated reaction. This study aims to conduct microscale characterization of geopolymer paste and mechanical properties of pervious concrete. Metakaolin (MK) and fly ash (FA) were used to synthesize geopolymer with granulated blast furnace slag (GBFS) as admixture.

‪Jadambaa Temuujin, PhD (Eng), DSc (Chem)‬ - ‪Google Scholar‬

Influence of calcium compounds on the mechanical properties of fly ash geopolymer pastes J Temuujin, A Van Riessen, R Williams Journal of hazardous materials 167 (1-3), 82-88, 2009

(PDF) Study on the physical and mechanical property of ...

Keywords: Fly Ash, OPC, Compressive Strength, Pastes, UPV. 1. Introduction More than 160 million tonnes of fly ash is being produced by thermal power plant in India (A. K. Jain, 2011). The disposal of fly ash is now a significant concern for the electricity manufacturing plants.

MECHANICAL AND MICROSTRUCTURAL PROPERTIES OF THE …

The results have shown that the mechanical properties of the fly-ash-based geopolymer paste and mortar greatly depend on the reaction parameters of the geopolymerization process. Depending on the reaction parameters, the compressive strength of fly-ash-based geopolymers may be considerably increased with an addition of sand.

(PDF) Mechanical and physical properties of metakaolin ...

It was observed that the fly ash geopolymer paste sample had a optimum results. The compressive strength value for 28 days was 53.92 MPa and the value of water absorption were 0.003 % and porosity ...