Effect of elevated temperature on alkali-activated geopolymeric binders compared to portland cement-based binders

Rivera, O.G.; Long, Wendy R.; Weiss, Charles; Moser, Robert D.; Williams, Brett A.; Torres-Cancel, K.; Gore, Ecaterina; Allison, P. G.

doi:10.1016/j.cemconres.2016.09.013

Cited by 117 publications

(55 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The SFB's strength increased with the heat-curing temperature rose, when the temperature was below 90 • C [20], indicating that the binders are applicable for the 85 • C geothermal environment [2,21]. Additionally, the cement containing slag also exhibited a better compressive strength and water permeability than the Portland cement [22].…”

Section: Introductionmentioning

confidence: 97%

The Self-Degradation Mechanism of Polyvinyl Chloride-Modified Slag/Fly Ash Binder for Geothermal Wells

et al. 2019

View full text Add to dashboard Cite

Polyvinyl chloride (PVC) releases hydrochloric acid (HCl) during its thermal degradation, and hydrochloric acid can react with hydration products of alkali-activated binders. According to this characteristic of PVC and the temperature change that occurs during the development of a geothermal well, the PVC was added into slag/fly ash binder to develop self-degradable materials. The thermal degradation properties of PVC, compressive strength, hydration products, and microstructure of binders at different stages were tested, in order to study the degradation mechanism of the material. It was found that 20% PVC reduced the compressive strength, decreasing the level of binder from 13.95% to 76.63%. The mechanism of PVC promoting the material degradation mainly includes the following: (1) the thermal degradation of PVC increases the number of multiple damage pores in the material, at a high temperature; (2) HCl generated by the PVC thermal degradation reacts with the binder gels, and breaks them into particles; and (3) HCl also reacts with other substances in the binder, including CaCO3 and NaOH in the pore solution.

show abstract

Section: Introductionmentioning

confidence: 97%

The Self-Degradation Mechanism of Polyvinyl Chloride-Modified Slag/Fly Ash Binder for Geothermal Wells

et al. 2019

View full text Add to dashboard Cite

show abstract

“…The geopolymer gained popularity because of the potential low CO 2 emission and energy efficiency during its manufacturing compared to conventional cement [3,4]. Moreover, the superior thermal stability of geopolymer compared to Portland cement has also increased the interest in that material for high-temperature applications [5]. However, this characteristic is closely related to the type of aluminosilicate used as well as the synthesis conditions [6][7][8].…”

Section: Introductionmentioning

confidence: 99%

Phase and dimensional stability of volcanic ash-based phosphate inorganic polymers at elevated temperatures

Djobo

Elimbi

2020

SN Appl. Sci.

View full text Add to dashboard Cite

Phosphate geopolymers are part of chemically bonded phosphate cements obtained from an aluminosilicate and phosphate solution. Their structure consisting of phosphate bonds makes them suitable for use as refractory material. This study deals with the influence of phosphoric acid concentration (6, 8 and 10 mol/L) on the stability of volcanic ash-based phosphate geopolymers exposed to 100, 600 and 1000 °C. The results reveal that the onset of crystallization is about 600 °C with the formation of aluminum phosphate (V) and tridymite, then crystallization of iron (III) phosphate (V) and hematite at 1000 °C. The degree of crystallization of these phases increases with phosphoric acid concentration. The geopolymers obtained with 8 mol/L of phosphoric acid showed the best thermal stability at 1000 °C in terms of compressive strength change. The maximum thermal linear shrinkage recorded was 3%. The major phases of all geopolymers remain stable up to 1000 °C, after which the melting of phases happens.

show abstract

“…The individual pores contribute to the porosity, so there is a need to understand the type of pores present in concrete. The pores are classified into two categories (a) gel pore, capillary pores, entrapped and entrained pores are characteristics of pores, while(b) macro pores, micro pores, meso pores, and larger pores are categorized according to the sizes of pores (Vodák et al 2004;Rivera et al 2016). Many techniques are available to determine the porosity in concrete such as pressure method, air-void analyzer, stereoscopic and microscopic methods (Moravcová et al 2016), torrent permeability tester (Kucharczyková et al 2010), mercury intrusion porosimetry (MIP) method widely used by researchers (Piasta et al 1984;Abell et al 1999;Chan et al 1999;Diamond 2000;Lee et al 2017), ultrasound method (Benouis and Grini 2011), water vapor adsorption, nitrogen adsorption (Moravcová et al 2016); but the limitation of these tests is that they assume that the pore geometry is regular and all the pores are interconnected.…”

Section: Introductionmentioning

confidence: 99%

Estimation of Porosity and Pore Distribution in Hydrated Portland Cement at Elevated Temperatures using Synchrotron Micro Tomography

Pavani

Tadepalli

Agarwal

2019

ACT

View full text Add to dashboard Cite

The porosity of concrete affects the mechanical properties and durability, during its exposure to extreme temperatures where the chemical and physical changes in PC affect the integrity of concrete as a whole because of its binding properties. An attempt is made to analyze the porosity in hydrated PC using synchrotron micro-tomography at temperatures of 27°C, 100°C, 400°C, 500°C, and 800°C. These temperatures are significant in the context of the mass loss and phase changes taking place during the thermal analysis. Image analysis is carried out to estimate porosity, radius, and circularity of pores for all the individual 2D slices. 3D analysis is carried out to estimate the diameter, area, and volume of pores present in the sample. The number of pores in the 2D slices has increased from 5974 to 11564 at 27°C and 800°C; while the total number of pores present in the sample at 27°C is 317 and at 800°C it is 3361. With the increase in temperatures, the area of pores 947 µm 2 contributed to 44.16 volume percent at 27°C, whereas at the temperatures of 800°C the area of 136 µm 2 pores volume percent is 41.

show abstract

Effect of elevated temperature on alkali-activated geopolymeric binders compared to portland cement-based binders

Cited by 117 publications

References 17 publications

The Self-Degradation Mechanism of Polyvinyl Chloride-Modified Slag/Fly Ash Binder for Geothermal Wells

The Self-Degradation Mechanism of Polyvinyl Chloride-Modified Slag/Fly Ash Binder for Geothermal Wells

Phase and dimensional stability of volcanic ash-based phosphate inorganic polymers at elevated temperatures

Estimation of Porosity and Pore Distribution in Hydrated Portland Cement at Elevated Temperatures using Synchrotron Micro Tomography

Contact Info

Product

Resources

About