Publication detail

Structure development study of porous concrete with fluidized-bed combustion ash admixture

ČERNÝ, V. MELICHAR, J. FLEISCHHACKER, J. DROCHYTKA, R.

Original Title

Structure development study of porous concrete with fluidized-bed combustion ash admixture

Type

journal article in Scopus

Language

English

Original Abstract

Because of its correlation between compressive strength and density, autoclaved aerated concrete (AAC) is a very suitable building material for many applications. Optimal macrostructure of the AAC skeleton is composed by small air pores. On the other hand, the well grown crystals of 11 Å tobermorite represent the most important part of the microstructure. The mineral is formed in hyper-alkaline, hydrothermal environment of the CaO – SiO2 – Al2O3 – H2O system. The main objective of this article is to study the influence of the fluidized bed combustion ash, as gypsum and partially lime alternative. Ground quartz sand, with an admixture of fluidized combustion ash, was used as the initial silica material. In order to reach the Ca/Si molar ratio of 0.73, the main silica sources were mixed together. As the instrument for the hydrothermal synthesis, carried out in the saturated steam environment at the pressure of 1.3 MPa and 185 °C for 12 hours, a laboratory autoclave was used. As the parameters determined to analyse physical-mechanical properties of the samples, density and compressive strength were chosen. X-ray diffraction method was used to observe the growth of the main mineralogical phases and scanning electron microscope (SEM) was used for crystal observation. From the results it is apparent that the fluidized bed combustion ash had a significant influence to tobermorite crystallization and formation.

Keywords

Autoclaved Aerated Concrete (AAC), Calcium silicate hydrates (CSH), Fly Ash (FA), Quartz sand, Fluidized Bed Combustion Ash (FBCA), hydrothermal reactions, tobermorite, katoite, sulfate admixture, Rietveld refinement

Authors

ČERNÝ, V.; MELICHAR, J.; FLEISCHHACKER, J.; DROCHYTKA, R.

Released

18. 12. 2017

ISBN

1804-0195

Periodical

Waste forum

Year of study

2017

Number

4

State

Czech Republic

Pages from

267

Pages to

275

Pages count

9

BibTex

@article{BUT143743,
  author="Vít {Černý} and Jindřich {Melichar} and Ján {Fleischhacker} and Rostislav {Drochytka}",
  title="Structure development study of porous concrete with fluidized-bed combustion ash admixture",
  journal="Waste forum",
  year="2017",
  volume="2017",
  number="4",
  pages="267--275",
  issn="1804-0195"
}