Preparation and characterization of waterproof autoclaved aerated concrete using molybdenum tailings as the raw materials

2022 ◽  
pp. 104036
Author(s):  
Chuanlong Shan ◽  
Zanzhong Yang ◽  
Zhen Su ◽  
Ramachandran Rajan ◽  
Xuexia Zhou ◽  
...  
Keyword(s):  
Raw Materials ◽  
Autoclaved Aerated Concrete ◽  
Aerated Concrete

Aluminum silicate recycling raw materials for production of autoclaved aerated concrete

ce/papers ◽  
2018 ◽  
Vol 2 (4) ◽  
pp. 215-221
Author(s):  
Fumiaki Matsushita ◽  
Kouichi Imasawa ◽  
Sumio Shibata ◽  
Masatoshi Horiguchi
Keyword(s):  
Raw Materials ◽  
Aluminum Silicate ◽  
Autoclaved Aerated Concrete ◽  
Aerated Concrete

Influence of Gypsum Additive on the Formation of Tobermorite in Autoclaved Aerated Concrete

2016 ◽  
Vol 714 ◽  
pp. 116-121 ◽  
Author(s):  
Ester Helanova ◽  
Rostislav Drochytka ◽  
Vit Cerný
Keyword(s):  
Chemical Composition ◽  
Hydrothermal Reaction ◽  
Raw Materials ◽  
Fly Ashes ◽  
Sem Images ◽  
X Ray ◽  
Autoclaved Aerated Concrete ◽  
Variable Chemical ◽  
Aerated Concrete

The quality of the aerated concrete strongly depends on the chemical composition of the raw materials, as well as the process of the hydrothermal reaction during autoclaving. Due to the variable chemical composition of fly ashes, it is necessary to identify the effect of each ion on the formation of the microstructure of aerated concrete. This paper examines the process of formation of tobermorite with the addition of sulphates in various percentage representation. The microstructure of aerated concrete is assessed using SEM images and the mineralogical by means of X-ray analysis.

scholarly journals FOR THE STUDY OF PECULIARITIES OF STRUCTURE FORMATION OF COMPOSITE BINDERS FOR NON-AUTOCLAVED AERATED CONCRETE

2020 ◽  
pp. 41-47 ◽  
Author(s):  
V. Lesovik ◽  
M. Absimetov ◽  
M. Elistratkin ◽  
S. Shatalova
Keyword(s):  
Structure Formation ◽  
Raw Materials ◽  
Stage Structure ◽  
Average Density ◽  
Strength Performance ◽  
Molding Mixture ◽  
Autoclaved Aerated Concrete ◽  
Wide Range ◽  
Mineral Additive ◽  
Aerated Concrete

the basis of the modern market of cellular concrete is autoclaved gas silicate. At the same time, non-autoclaved aerated concrete is largely a more technological material, allowing the variation of its properties within a wide range, having a potentially wider field of application, less costly in the organization of production, which is of great importance for small and medium-sized businesses. The main problem of non-autoclaved aerated concrete is a higher cost of raw materials compared to silicate, and 20...30% lower strength performance. The proposed solution to this problem is the development of special composite binders with a limited content of clinker and mineral additives of various genetic types, taking into account the peculiarities of the two-stage structure formation of the material – gas porization and the formation of the microstructure of the stone. The article deals with some aspects of the interaction in the system “mineral additive – gypsum – by-products of the gas release reaction” in terms of the effect on the viscosity of the swelling mass and the strength of the stone at different times of hardening. Recommendations are given on the preferred compositions of composite binders and dosages of gypsum in the molding mixture when producing a material with an average density in the range of 500...700 kg/m3.

Development of a New Thermal Insulating Concrete Block by Spent Polystyrene Foam

2010 ◽  
Vol 450 ◽  
pp. 198-201 ◽  
Author(s):  
Li Peng Cai ◽  
Ying Wei Yun ◽  
Ii Young Jang ◽  
Seong Kyum Kim
Keyword(s):  
Raw Materials ◽  
Concrete Block ◽  
Standard Test ◽  
Test Method ◽  
Wall Material ◽  
Polystyrene Foam ◽  
Autoclaved Aerated Concrete ◽  
Thermal Insulating ◽  
Comprehensive Properties ◽  
Aerated Concrete

In this research, a new Thermal Insulating Concrete Block (TICB) is produced via “sandwich” structure by spent polystyrene foam, cement and other raw materials. According to the concerned China Standard Test Method for Building Material, the main properties of this TICB are measured successfully. By comparing its properties with those of autoclaved aerated concrete block as wall material, it can be concluded that comprehensive properties of this concrete block is better than those of autoclaved aerated concrete block. The extrusive advantage of producing this TICB is that large amount of spent polystyrene foam which is hard to be decomposed as industrial waste can be consumed. This is propitious to environmental protection and energy conservation. Therefore, TICB studied in this paper is one kind of green environmental wall material with bright prospect.

scholarly journals Influence of addition of calcium sulfate dihydrate on drying of autoclaved aerated concrete

2017 ◽  
Vol 7 (1) ◽  
pp. 273-278 ◽  
Author(s):  
Dorota Małaszkiewicz ◽  
Jacek Chojnowski
Keyword(s):  
Calcium Sulfate ◽  
Hydrothermal Reaction ◽  
Raw Materials ◽  
Capillary Rise ◽  
Initial Moisture Content ◽  
Material Structure ◽  
Performance Parameters ◽  
Autoclaved Aerated Concrete ◽  
Calcium Sulfate Dihydrate ◽  
Aerated Concrete

AbstractThe quality of the autoclaved aerated concrete (AAC) strongly depends on the chemical composition of the raw materials, as well as on the process of the hydrothermal reaction during autoclaving. Performance parameters depend on material structure: fine micron-scale matrix porosity generated by the packing of thin tobermorite plates and coarse aeration pores arising from the foaming of wet mix. In this study the binder varied in calcium sulfate dihydrate (CaSO4⋅2H2O) content. Five series of AAC specimens were produced, with gypsum content 0; 0.55; 1.15; 2.3 and 3.5% of dry mass respectively. AAC units were produced in UNIPOL technology. The study presents experimental results of AAC moisture stabilization. The initial moisture content was determined directly after autoclaving. Slower drying process was observed for samples containing over 2% of gypsum. Whereas other performance parameters, compressive and tensile strength, as well as water absorption and capillary rise, were significantly better comparing to the reference AAC samples.

Advanced Rietveld refinement and SEM analysis of tobermorite in chemically diverse autoclaved aerated concrete

2019 ◽  
Vol 34 (2) ◽  
pp. 143-150 ◽  
Author(s):  
J. Schreiner ◽  
F. Goetz-Neunhoeffer ◽  
J. Neubauer ◽  
S. Volkmann ◽  
S. Bergold ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Structural Properties ◽  
Rietveld Refinement ◽  
Raw Materials ◽  
Xrd Analysis ◽  
Sem Analysis ◽  
Lattice Parameters ◽  
Autoclaved Aerated Concrete ◽  
Peak Broadening ◽  
Aerated Concrete

Changes of structural properties of tobermorite in autoclaved aerated concrete (AAC) for various compositions were characterized and the disadvantages of SEM analysis in this context are discussed. The influence of variations in the chemical composition of raw materials on lattice parameters, morphology and domain sizes of tobermorite was investigated by XRD and for comparison by SEM analysis. Particularly the effect of substitution by Al3+ and (SO4)2− in tobermorite structure was examined. The dimensions of coherently scattering domains were calculated based on the refinement of anisotropic peak broadening of tobermorite in XRD diffractograms using a Rietveld compatible approach. No effect of (SO4)2− on the domain sizes and lattice parameters of tobermorite could be observed. The amount of anhydrite detected by quantitative XRD analysis indicates that all of the available (SO4)2− is present as anhydrite. Lath-like shapes of domains and a larger c parameter are calculated whenever Al3+ is incorporated in a considerable amount. Formation of katoite can be observed very clearly in SEM micrographs whenever the amount of available Al3+ exceeds a distinct value in the dry mix. The effect of Al3+ and (SO4)2− on tobermorite morphology could not be observed clearly by SEM analysis in AAC samples.

Formation of Tobermorite at Different Materials Composition of Aerated Concrete

2015 ◽  
Vol 752-753 ◽  
pp. 247-250 ◽  
Author(s):  
Ester Venhodová ◽  
Radek Janovský ◽  
Rostislav Drochytka
Keyword(s):  
Chemical Composition ◽  
Raw Materials ◽  
Molar Ratio ◽  
Autoclaved Aerated Concrete ◽  
Silica Source ◽  
Aerated Concrete

For the production of quality autoclaved aerated concrete product is necessary to know the chemical composition of raw materials and with regard to that optimize the recipe. This paper deals with the verification of the influence raw materials mixture ́s chemical composition, the reactivity of the silica source and the molar ratio C/S on the shape and amount of tobermorite crystals in autoclaved aerated concrete.

Non-Autoclaved Aerated Concrete on the Basis of Composite Binder Using Technogenic Raw Materials

2019 ◽  
Vol 945 ◽  
pp. 205-211 ◽  
Author(s):  
Valery S. Lesovik ◽  
M.Y. Elistratkin ◽  
E.S. Glagolev ◽  
V.V. Voronov ◽  
M.V. Absimetov
Keyword(s):  
Formation Control ◽  
Raw Materials ◽  
Pore Space ◽  
Autoclaved Aerated Concrete ◽  
Concrete Production ◽  
Mineral Additive ◽  
Processing Wastes ◽  
Aerated Concrete ◽  
Technogenic Raw Materials ◽  
Production Organization

Non-autoclaved aerated concrete certain advantages are significantly lower production organization costs and technology energy intensity due to the lack of autoclave curing, the possibility of different scales industries foundation as well as monolithic construction applications. All of this allows to solve complex problems of various purposes buildings erection, heat and noise insulation. Portland cement consumption significant reduction and material properties management can be achieved through use of composite binders containing local natural and technogenic components selected on the basis of their genesis and properties. The applicability of heavy concrete and ceramic bricks processing wastes as well as such large-tonnage extraction of iron ore as sandstones granulation selection as mineral additive for non-autoclaved aerated concrete production as well as a number of accompanying issues of the of a high-quality pore space structures formation control are considered in the present article.

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