Influence on rheological behavior of montar with addition of fly ash from bayer process fluidized bed boilers and construction/ Influência no comportamento reológico de montar com adição de cinza voada de caldeiras e construção de cama fluidizadas no processo de Bayer
DOI:
https://doi.org/10.34117/bjdv5n12-362Keywords:
Mortars, pozzolanic activity, rheology, apparent viscosityAbstract
Fly ash obtained from coal combustion in fluidized bed boilers has been used in civil construction to partially replace Portland cement, due to its pozzolanic activities, and thus minimizing the accumulation of industrial waste. The rheological characteristics of six composition of mortars were studied on six differents proportions of cement, construction waste generation (CWG) and fly ash (FA). For the rheological tests, a coaxial cylinder viscometer was used, varying the shear rate from 0 to 600 s-1 at 28 ºC, [1] in the interval time of 120s (in 120s time interval). Granulometric analysis, X-ray diffraction (XRD), X-ray fluorescence (XRF) and scanning electron microscope (SEM) tests were performed. The results showed that fly ash incorporation is the main factor for changing behavior from rheopecthic to thixotropic, in the avaluated traces. The experimental data was well fitted in Herschel-Bulkley rheological model.
References
A. J. Curtius, H. D. Fiedler, Analysis of metals and analytical quality. Environment and coal: exploration and use impacts. Porto Alegre: FEPAM, 2002. p. 211-227 [in Portuguese].
C.E. Pozzobon, Technological applications for coal ash produced at the Jorge Lacerda thermoelectric complex. 1999, 113p. Dissertation (master degree in civil engineering) - Post-graduation program in civil engineering, Federal University of Santa Catarina, Florianópolis [in Portuguese].
J. P. Scandolara, Properties of mortars obtained by the partial replacement of Portland cement with particulate brick tailings. 2010. Dissertation (Master in Science and Materials Engineering) - Federal University of Santa Catarina, Center of Technological Sciences - CCT, Joinville [in Portuguese].
C. S Poon, Y.L.Wong e L. Lam, The influence of different curing conditions on the pore structure and related properties of fly-ash cement pastes and mortars. Construction and building, v. 11. Great Britain, p. 383-393, 1997.
J.J.Beaudoin, Handbook of analytical techniques in concrete science and technology, New York, Noyes / William Andrew V.S. Ramachandran, 2001.
L. Senff, D. Hotza, W.L. Repette, Rhelogycal behaviour of cement pastes with addition of silica fume, nanosilica and polycarboxilic dispersant Revista Matéria, v. 15, nº 1, p. 012 – 020, 2010.
A. L. G. Gastaldini e G. C. Isaia, Chloride permeability of high performance concrete with mineral addition: binary and ternary mixtures. INTERNATIONAL CONFERENCE ON HIGH PERFORMANCE CONCRETE, 2. Gramado, Brasil, Proceedings, 1999. 1 CD-ROM.
Brazilian Association of Technical Standards, NBR 7217, Determination of granulometric composition of aggregates, Rio de Janeiro, 1987.
Brazilian Association of Technical Standards, NBR 7211, Aggregates for concrete - specification, Rio de Janeiro, 2005.
C. A. F. Rocha Junior, S. C. A. Santos, C. A. Souza, R. S. Angélica, R. F. Neves, Synthesis of zeolites from fly ash from boilers: physical, chemical and mineralogical characterization. Cerâmica 58 (2012), 43-52.
J. S. Siqueira, C. A. G. Souza, J. A. S. Souza, Reuse of ash coal in the formulation of mortars. Cerâmica 58 (2012) 275-279 [in Portuguese].
P. F. G Banfill, M. Criado, A Palomo, A.Fernández-Jiménez, Alkali activated fly ash: Effect of admixtures on paste rheology. Rheologica Acta, v. 48, nº. 4, 2009, p. 447-455.
L. Senff, D. Hotza., J.A. Labrincha, Effect of red mud addition on the rheological behaviour and on hardened state characteristics of cement mortar, Civil Engineering Dimension, Vol. 12, nº. 1, March 2010, 18- 22.
P. Santos Souza, Ciência e Tecnologia de Argilas,2ª Ed., Vol. 2. São Paulo: Edgar Blucher, (1989) 113. [in Portuguese].
G. A., Schramm, Practical approach to rheology and rheometry. 2ª. Ed.. Karlsruche: Gebrueder HAAKE GmbH, 2000.
I. Oliveira, A. Studart, R. Pillegi, V. Pandolfelli, Dispersão e empacotamento de partículas – Princípios e aplicações em processamento cerâmico.18ª ed. São Paulo, Fazendo Arte, 2000 [in Portuguese].
K.Wang, M.S. Konsta-Gdoutos e S.P.Shah, Hydration, rheology, and strength of ordinary Portland cement (OPC) cement kiln dust (CKD) slag binders, ACI materials journal, 99(2), March-April, 173-179 (2002).
A. Camões, R.M. Ferreira, B. Aguiar, e S. JALALI, Durability of high performance concrete with fly ash, Concrete for Extreme Conditions, Proceedings of the International Conference Challenges of Concrete Construction, Dundee, Scotland, U.K. , 357-366 (2002).
