Study of the binary system fly ash/sugarcane bagasse ash (FA/SCBA) in SiO2/K2O alkali-activated binders

This present study investigates the effects of CaSO4 incorporation on the pore structure and drying shrinkage of alkali-activated slag and fly ash. The slag and fly ash were activated at a 5:5 ratio by weighing with a sodium silicate. Thereafter, 0%, 5%, 10%, and 15% of CaSO4 were incorporated to investigate the changes in phase formation and internal pore structure. X-Ray Diffraction (XRD), thermogravimetry (TG)/derivative thermogravimetry (DTG), mercury intrusion porosimetry (MIP), nuclear magnetic resonance (NMR), and drying shrinkage tests were carried out to find the correlation between the pore structure and drying shrinkage of the specimens. The results showed that CaSO4 incorporation increased the formation of thenardite, and these phase changes affected the pore structure of the activated fly ash and slag. The increase in the CaSO4 content increased the pore distribution in the mesopore. As a result, the capillary tension and drying shrinkage decreased.

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Leaching, carbonation and chloride ingress in reinforced alkali-activated fly ash mortars

MATEC Web of Conferences ◽

10.1051/matecconf/201819902025 ◽

2018 ◽

Vol 199 ◽

pp. 02025 ◽

Cited By ~ 1

Author(s):

Gregor J. G. Gluth ◽

Petr Hlaváček ◽

Steffi Reinemann ◽

Gino Ebell ◽

Jürgen Mietz

Keyword(s):

Fly Ash ◽

Visual Inspection ◽

Electrochemical Behaviour ◽

Transport Coefficients ◽

Chloride Penetration ◽

Chloride Ingress ◽

Reaction Products ◽

Steel Bars ◽

Alkali Activated Binders ◽

Alkali Activated

Alkali-activated fly ash mortars were studied with regard to durability-relevant transport coefficients and the electrochemical behaviour of embedded carbon steel bars on exposure of the mortars to leaching, carbonation and chloride penetration environments. The transport coefficients differed considerably between different formulations, being lowest for a mortar with BFS addition, but still acceptable for one of the purely fly ash-based mortars. Leaching over a period of ~300 days in de-ionized water did not lead to observable corrosion of the embedded steel, as shown by the electrochemical data and visual inspection of the steel. Exposure to 100 % CO2 atmosphere caused steel depassivation within approx. two weeks; in addition, indications of a deterioration of the mortar were observed. The results are discussed in the context of the different reaction products expected in highand low-Ca alkali-activated binders, and the alterations caused by leaching and carbonation.

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Chloride-induced reinforcing steel corrosion in ternary concretes containing fly ash and untreated sugarcane bagasse ash

Construction and Building Materials ◽

10.1016/j.conbuildmat.2018.12.004 ◽

2019 ◽

Vol 198 ◽

pp. 608-618 ◽

Cited By ~ 8

Author(s):

Víctor Alberto Franco-Luján ◽

Marco Antonio Maldonado-García ◽

José Manuel Mendoza-Rangel ◽

Pedro Montes-García

Keyword(s):

Fly Ash ◽

Sugarcane Bagasse ◽

Steel Corrosion ◽

Reinforcing Steel ◽

Sugarcane Bagasse Ash ◽

Reinforcing Steel Corrosion

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Effects of slag substitution on physical and mechanical properties of fly ash-based alkali activated binders (AABs)

Cement and Concrete Research ◽

10.1016/j.cemconres.2019.05.003 ◽

2019 ◽

Vol 122 ◽

pp. 118-135 ◽

Cited By ~ 12

Author(s):

Ali Rafeet ◽

Raffaele Vinai ◽

Marios Soutsos ◽

Wei Sha

Keyword(s):

Mechanical Properties ◽

Fly Ash ◽

Physical And Mechanical Properties ◽

Alkali Activated Binders ◽

Alkali Activated

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Quantification of geographical proximity of sugarcane bagasse ash sources to ready-mix concrete plants for sustainable waste management and recycling

Waste Management & Research ◽

10.1177/0734242x20945375 ◽

2020 ◽

pp. 0734242X2094537 ◽

Cited By ~ 1

Author(s):

Gopinath Athira ◽

Abdulsalam Bahurudeen ◽

Vijaya Sukumar Vishnu

Keyword(s):

Fly Ash ◽

Sugarcane Bagasse ◽

Raw Materials ◽

Disposal Site ◽

Partial Replacement ◽

Geographic Proximity ◽

Study Results ◽

Concrete Production ◽

Sugarcane Bagasse Ash ◽

Ready Mix Concrete

As stated in the European Commission’s waste framework directive, the geographic proximity of wastes to the potential recovery/disposal site is of paramount importance in attaining an effective resource recycling paradigm. The global interest in achieving an end-of-waste scenario encourages the recovery of useful products/secondary raw materials from locally available waste materials. Sugarcane bagasse ash is an abundantly available waste (44,200 tonnes day–1) from sugar plants in India which has the potential to be used as a partial replacement to cement in ready-mix concrete plants. Although pozzolanic performance of sugarcane bagasse ash and its ability in reducing the carbon emissions associated with concrete production have been reported in earlier research studies, its use in concrete is hindered due to the lack of availability and accessibility data. In this study, the geographical distribution of sugar plants and the available quantity of sugarcane bagasse ash in India have been determined. In addition, a detailed network analysis using a geographic information system was conducted to quantify the geographic proximity of bagasse ash, fly ash and slag sources to ready-mix concrete plants. The study results indicate that for most of the ready-mix concrete plants in India, the probability of having a bagasse ash source in proximity is higher than the probability of encountering slag/fly ash sources.

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