CC BY
8doi: 10.18720/MCE.83.6
Strength and phase composition of autoclaved material:
an approximation
Взаимосвязь прочности и фазового состава автоклавированного материала
G.I. Ovcharenko*, D.I. Gilmiyarov,
Polzunov Altai State Technical University, Barnaul, Russia
Д-р техн. наук, заведующий кафедрой Г.И. Овчаренко*,
канд. техн. наук, начальник лаборатории Д.И. Гильмияров,
Алтайский государственный технический университет им. И.И.Ползунова, Барнаул, Россия
Key words: autoclaved building materials; lime-fly ash mixtures; Na2SO4 addition; phase composition; strength of the stone; interrelationships
Ключевые слова: автоклавные строительные материалы; известково-зольные смеси; добавка Na2SO4; фазовый состав; прочность камня; взаимосвязи
Abstract. The purpose of this work was to identify the relationship between the phase composition and strength of autoclaved pressed stone from a mixture of lime and ash of CHP in the presence of Na2SO4. From these mixtures are made such building materials as silicate brick and blocks from autoclaved cellular concrete. The phase analysis of the autoclaved samples was carried out by X-ray and thermal methods. It was found that the mixtures studied after autoclaving for 8; 50 and 100 hours at 0.8 MPa isotherm with no addition or with 1 and 2% Na2SO4 is represented by gel-like phase C-A-S-H, aluminum substituted tobermorite, hydrogarnet katoite. Adding of 1 and 2% Na2SO4 makes no qualitative change in phase composition, but significantly redistribute the phase composition and increase the rate of phase formation. Thus 2 % Na2SO4 contributes to a substantial increase in the synthesis of Al-tobermorite, but reduces the C-A-S-H phase formation. Katoite hydrogarnet content remains unchanged. The degree of hydration of the composition with 2% Na2SO4 for 8 hours of autoclaving is the same as for 100 hours of treatment without an additive. This increases the strength of the material by 1.65 times with the same 8 hour steaming time. Strength of the stone is always directly proportional to the content of a gel C-A-S-H phase. Its content is proportional to the number of Al-tobermorite in non-additional mixtures, but does not correspond to the content of tobermorite in compositions with addition of 2 % Na2SO4. Keywords: autoclaved building materials, lime-fly ash mixtures, Na2SO4 addition, phase composition, strength of the stone, interrelationships.
Аннотация. Целью данной работы было выявить связь между фазовым составом и прочностью автоклавного прессованного камня из смеси извести и золы ТЭЦ в присутствии Na2SO4. Из подобных смесей изготавливаются такие строительные материалы как силикатный кирпич и блоки из автоклавного ячеистого бетона. Фазовый анализ автоклавированных образцов проводили рентгенофазовым и термическими методами. Было обнаружено, что смеси, изученные после автоклавирования при 8; 50 и 100 часов при изотерме 0,8 МПа без добавления или с 1 и 2% Na2SO4 содержат гелевидную фазу C-A-S-H, алюминий замещенный тоберморит, гидрогранат катоит. Добавление 1 и 2% Na2SO4 не приводит к качественному изменению фазового состава, но значительно перераспределяют фазовый состав и увеличивает скорость фазообразования. Таким образом, 2% Na2SO4 способствует существенному увеличению содержания Al-тоберморита, но уменьшает образование фазы C-A-S-H. Содержание гидрограната остается неизменным. Степень гидратации композиции с 2% Na2SO4 за 8 часов автоклавирования такая же как за 100 часов обработки без добавки. Это увеличивает прочность материала в 1,65 раза при одинаковом 8 часовом времени запаривания. Прочность камня всегда прямо пропорциональна содержанию гелевидной фазы C-A-S-H. Её содержание пропорционально содержанию Al-тоберморита в смесях без добавки, но не соответствует содержанию тоберморита в композициях с добавлением 2% Na2SO4. Ключевые слова: автоклавные строительные материалы, известково-зольные смеси, добавка Na2SO4, фазовый состав, прочность камня, взаимосвязи.
1. Introduction
The object of research in this paper is to reveal the relationship between the strength of autoclaved stone based on the lime-ash mixture and its phase composition.
The phase composition of hydrates of autoclave stone on the basis of lime and aluminosilicate raw materials still provokes discussions, not to mention the interrelation between the components of the phase composition and its strength. At the same time, numerous silicate brick plants are used as the main component or as an additive to the ash class F of the CHP.
The main law of the strength formation of silicate autoclaved materials have been discussed since the beginning of the 50s of the 20th century, when G.L. Kalouzek had found its direct dependence on the quantity of generated 11.3 angstrom tobermorite [1]. Then H.F.W. Taylor objected Kalouzek, noting that the strength of any material is a function of its density, and, for autoclaved materials, it also depends on presence of gel phase in them. The effect of a gel phase on the strength had been previously mentioned in the works of P.I. Bozhenov for whom Taylor referred. However, both P.I. Bozhenov, and Taylor have not reported quantitative relationships in those years. It was only 1977, when Taylor published the article [2] proving a direct link of strength of lime-silica material with a number of C-S-H gel being formed. Taylor stated a brief review of these issues in the last lifetime edition of "Chemistry of cement" [3], also specifying differences in opinion on this issue, particularly in the extent beneficial to crystallize a gel phase.
When using various aluminosilicate materials, including it in the form of CHP ash of the aluminosilicate composition, as well as Portland cements the silica component, phase formation of autoclave materials becomes more complicated. Even the qualitative composition of the phases had caused discussions. It was only in the 2000s, when the publications of A.S. Ray in conjunction with D.S. Klimesch [4] were issued, and as well of Japanese researchers [5] and others [6, 7], which allowed to interpret and quantify unambiguously the phases being formed in such systems. The issue of the interrelation of the phase composition and strength of autoclave stone composed of lime-aluminosilicate raw materials remained open. Because synthetic tobermorites and their Al- and Fe-substituted forms easily synthesized under saturated steam or in hydrothermal conditions at temperatures from 80 to 225 °C from a wide range starting materials, including various following mixtures: lime, zeolites, quartz, gibbsite, cement, clays, sodium silicate, ashes, cullet, trachyte and others [1, 8-19]. And the presence of a gel-like phase of the C-A-S-H type in these syntheses was often not paid attention. At the same time, publications on the features of the structure of the tobermorites and their analogs, the synthesis of minerals and their ion-exchange properties, do not give an answer to the question of the regularities in the formation of the strength of the stone on their basis [20-28].
Therefore, the purpose of this study was to establish such a relationship between the phase composition and strength for such an aluminosilicate raw material as ash.
For this, it was necessary to establish a reliable quantitative composition of phases of autoclave stone composed of alumino-silicate raw materials on the basis of the CHP ash, to use an addition that promotes redistribution of the main phases in order to disclose interrelations between the phase composition and strength of stone.
It follows from [5, 26] that the addition of AhO3 or SO3 in lime-silica autoclave composition accelerates crystallization of C-S-H gel phase and formation of larger amount of tobermorite. Furthermore, it is known that the presence of alkali in autoclave synthesis significantly accelerates the hydrate formation [29]. By definition, alumina is present in the aluminosilicate raw material. Therefore, Na2SO4was selected as an activator additive. Sodium sulphate contains the required group of SO3, and alkaline, released in hydrothermal reactions, will accelerate the synthesis and crystallization of hydrated phases. The possibility of such processes due to the high real defectness tobermorite structure [20, 30-37].
The relevance of this study is that, for aluminosilicate raw materials, the relationship between strength and phase composition for autoclave materials has not yet been established. At the same time, such aluminosilicate materials as CHP ashes are widely used in the technology of autoclave materials.
The purpose of this study is to establish a relationship between the strength and phase composition of autoclave material based on lime and aluminosilicate ash from CHP.
To achieve the goal it is necessary to solve the following tasks:
- investigate the strength and phase composition of lime-ash material in a wide range of phase composition changes;
- to increase the range of changes in the phase composition and strength of the stone, apply the method of prolonged autoclave treatment and intensification of the processes by the Na2SO4 additive-activator;
- to establish the relationship between the phase composition of lime-ash and its strength.
2. Materials and Methods
In experiment, was used electrostatic precipitator ash provided by burning coal (coal ash - CA) of Kuznetsk Basin brand G at Novosibirsk CHP-5 with the composition of unburned coal of 3.29 % (Table 1, recalculated on ignited product). Ash particles range from 1.5 to 250 ^m with an average diameter of 70.5 ^m (determined in an equipmentSALD-2101 Laser Diffraction Particle Size Analyzer - SHIMADZU, Japan). Calcium lime contained about 92 % of active CaO and MgO and, by main indicators, was consistent with first grade lime according to Russian standards. In some mixtures, it was used curing activator of Na2SO4 with 98 % content of the main substance.
Table1. Chemical composition of ash provided by Novosibirsk CHP-5
Material SiO2 AI2O3 Fe2O3 CaO MgO SO3 Total
CHP-5 ash 61.87 23.73 5.0 4.38 1.29 0.33 99.98
The ash was mixed with powdered lime with Blaine specific surface area of about 6.000 cm2/g with a ratio of 20 % basing on active CaO and MgO. In some mixtures with tempering water, Na2SO4 was added as hardening activator in an amount of 1 or 2% by weight. The raw material mixture was moistened, sealed in plastic containers and ensilaged at 60 0C for 2 hours to full lime hydration. After that, from that mass, it was formed cylinder samples of diameter and height of 50 mm at specific pressing pressure of 20 MPa, which were treated in an autoclave at 0.8 MPa with isothermal exposure of 8, 50 and 100 hours correspondingly. Samples strength tests were produced after their drying at 100 0C to constant mass. Six samples for test was chosen to ensure measurement error of not more than 3-5%. Some samples were taken out of those ones for analysis by methods of X-ray diffraction (XRD) and thermal analysis, including differential and thermal analysis (DTA), differential thermogravimetric analysis (DTG), and thermogravimetric analysis (TG).The X-ray diffraction analysis was performed on a DRON-3 (Russia) with CuKa radiation at tube voltage of 40 kV and current of 25 A. The thermal analysis at rate of 10 deg/min was conducted using an equipment Netzsch STA 449C (Germany) in a closed crucible and helium flow to create not-oxidative environment and eliminate the effects of burning coal residues in the ash.
3. Results and Discussions
Figure 1 shows that with increasing isothermal hold up time from 8 to 100 hours, strength of lime-ash compositions without additional of Na2SO4is steadily increasing from 20 to 45.5 MPa. When injected with 1 and 2% Na2SO4, there is an inflection in strength at 50 hours of autoclaving, or composition strength decrease in proportion to additions at isotherm of 100 hours. At this, the samples with the addition of 2% sodium sulphate gain the main strength after the first 8 hours of heat treatment in the autoclave and then there is no substantial increase observed. Compared with the addition-free composition, the addition of 1 and 2% of sodium sulfate increases strength by 1.3 and 1.6 times respectively at isotherm autoclaving of 8 hours.
These data require an interpretation. For this it is necessary to determine the phase composition of
stone.
8 hours of isothermal exposure
50 hours of isothermal exposure
100 hours of
isothermal
exposure
Figure 1. Strength of lime-ash samples autoclaved at pressure of 0.8 MPA depending on time of isothermal exposure and addition of Na2SO4. Notice: L - lime, NS - Na2SO4, CA - coal ash
The composition of the formed hydrothermal synthesis products in the addition-free mixture according to XRF (Figure 2) is presented by the following main phases: 8 hours isotherm (X-ray pattern1) - residual portlandite Ca(OH)2 (4.91; 2.63; 1.80),the residual quartz ash of SiO2 (4.27; 3.35; 2.28; 1.80), synthesized tobermorite (11.48; 5.41; 3.08; 2.98; 2.79), calcite (3 04; 2.28; 1.93).In addition to these phases, there are reflections of hydrogarnets: katoite - 5.10; 2.79; 2.28; 1.67, and ferrous hydrogarnet -3.08; 2.74; 1.62. Probably, the presence of C-S-H phases (I and II) - peaks are 3.07 and 2.80, but reflections for these phases are absent at small angles (12.5 and 9.80*10-10 m). Increasing the isotherm up to 100 hours in the addition-free composition (X-ray pattern2), we observe portlandite disappearance, the proportion of silica is reduced, the proportion of tobermorite is increased, but not all peak intensities of tobermorite change proportionally - the peak of 5.41 decreases, the one of 2.98 remains unchanged, and the peaks of 11.60 and 3.08 increase. Instead of the 2.79 peak, the peak of 2.76 appears. The significant deviation of 11-angstrem peak of 11.30 to 11.60*10-10m should be noted. The peaks of katoite transform to reflections of ferrous hydrogarnet - 5.045; 3.08; 2.755; 1.62-1.63, although certain sources attribute the peak of 2.76 as well to katoite. Besidesof 1.1 nm of tobermorite and perhaps xonotlite (3.07-3.08; 2.83; 2.70), there are no peaks of other calcium hydrosilicates.
In the presence of 1 % Na2SO4 activator for 8 hours of treatment (X-ray pattern3), there is an intermediate phase composition reached compared with 8 and 100 hours without additive composition except of a significant increase in the peak of 2.76.It can be referred to katoite or ferrous hydrogarnet. 100 hour exposure in the presence of 2% Na2SO4 (X-ray pattern4) differs only slightly from the 100 hour exposure in a system without the activator, except of even larger decrease of quartz proportion and outlined supplements.
aX/uA
Figure 2. X-ray patterns of lime-ash stone of the 20 % lime, 80 % ash mixture, at: No. 1 - 8 h of isothermal exposure; No. 2 - at 100 h of isothermal exposure; No. 3 - 8 h of isothermal exposure with additive injection of 1% Na2SO4; No. 4 - 100 h of isothermal exposure with additive injection of 1% Na2SO4; No. 5 - 8 h of isothermal exposure with additive injection of 2 % Na2SO4; No. 6 - 100 h of isothermal exposure with additive injection of 2% Na2SO4.
Analysis of the mixture thermogram based on the ash of Novosibirsk CHP-5 at 8 hours of isothermal exposure (Figure 3) shows the effect of weight loss (DTG curve at approximately 95 °C, which is associated with removal of moisture adsorption. There we see presence of hydrogarnets that are noted with little effect at 373 °C. A large weight loss at 447 °C corresponds to residual portlandite Ca(OH)2. In the 700-780 °C interval, there occurs decomposition of calcium hydrosilicates, calcite, and probably, of C-A-S-H phase, dehydration of which is accompanied by a pronounced effect at 741 °C.H.F.W. Taylor also attributed this effect to amorphous hydrosilicate phase [2]. Tobermorite phase having significant deviations of XRD reflections from 11.3, represents aluminum substituted tobermorite with other impurities and thus loses weight at 180 0C, being much smaller than 240 0C [4].
At increasing the isothermal exposure to 100 hours, a differential curve of weight loss, DTG (Figure 4), represents a significant increase in endothermic effect at 86 °C and the disappearance of residual portlandite Ca(OH)2because of the formation of hydrate phases large number being a result of hydrothermal synthesis. For this, as additional evidence, the large weight loss may serve as evidence which is associated with the removal of moisture adsorption and with loss of water by the gel phase. Weight loss effect by hydrogarnet at 381 °C is registered. The weight loss at effects of 185 and 727 °C increases up to 2.4 %.
Figure 3. Thermogram of products of autoclave treatment basing on Novosibirsk CHP-5 ash at
20 % of lime at 8 hours of isothermal exposure
The thermogram of samples hydration products on the basis of Novosibirsk CHP-5 ash at 20 % of lime, with 8 hours of isothermal exposure with additional injection of 2% Na2SO4 (Figure 5) differs only slightly from the thermogram being addition-free of lime-ash mixture at 100 hours of isothermal exposure that indicates the activation of hydrothermal synthesis in the presence of sodium sulfate. However, with the activator additive, the proportion of C-A-S-H phase gets reduced, if judging by the weight loss at 727 °C endothermic effect.
Estimation of interrelation between strength of the stone with its composition of hydrate phases variety (Table 2) shows that it increases in proportion to the main XRD reflection of Al-tobermorite (11.5*10-10m), to increase in weight loss both at the temperature range 180 °C (tobermorite) and at 730 °C (gel C-A-S-H) that indicates the correct classifying of that effects to hydrated phases. This pattern holds true for both addition-free and Na2SO4-activator systems.
Figure 4. Thermogram of hydration products samples basing on Novosibirsk CHP-5 ash with 20 %
of lime at 100 hours of isothermal exposure
Figure 5. Thermogram of hydration products samples basing on Novosibirsk CHP-5 ash with 20 % of lime at 8 hours of isothermal exposure with additional injection of 2% Na2SO4.
Table 2 Strength and quantitative characteristics of phase contents in stone
Mass composition Isotherm of autoclaving, h Stone strength, MPa Peak intensity 11.5x10"10 mtobermorite (XRD) length, mm Weight loss DTG at 165190, 0C, % tobermorite Weight loss DTG at 373-381, 0C, % hydrogarnet katoite Weight loss DTG at439-447, 0C, % CA(OH)2 Weight loss DTG at725-735 0C, % gel C-A-S-H
Base composition 8 20 48 1.5 0.8 1.1 1.7
Base composition 100 46 77 2.4 1.0 ~ 2.4
Base composition + 1% Na2SO4 8 26 96 2.3 0.8 0.4 2.0
Base composition + 1% Na2SO4 100 41 107 2.7 1.0 -- 2.6
Base composition + 2% Na2SO4 8 31 60 2.3 0.9 -- 1.5
Base composition + 2% Na2SO4 100 34 112 2.9 1.0 -- 1.5
Note: base composition - 20% of lime + 80% of coal ash
Quantitative phase composition of autoclave stone, after its recalculation on corresponding compounds, is shown in Figure 6.
Figure 6. Quantitative phase composition of autoclave stone made of lime and ash.
Notice: L - lime, NS - Na2SO4, CA - coal ash
The interrelation between strength and phase composition of the stone of the studied compositions is shown in Figures 7-9 from which is obvious that the strength of Na2SO4-free compositions is directly proportional to the content of both the Al-tobermorite and gel phase of C-A-S-H (Figure 7). This interrelation becomes less pronounced, but still maintained at 1% of sodium sulfate (Figure 8). However, with addition of 2% Na2SO4(Figure 9), this relationship is not observed anymore. At this, a considerable increase in Al-tobermorite in this composition according to both the data of XRD and DTG does not correspond completely to a slight increase in stone's strength. However, a small amount of C-A-S-H phase here fully agrees with the same slight increase in strength.
Thus, the strength of the autoclave stone made of lime-ash mixtures always proportional to the content of gel C-A-S-H phase. At the same time, the content of the latter can be or can be absolutely not proportional to the amount of Al-tobermorite. It is typical that initiating the synthesis of Al-tobermorite with the Na2SO4-addition, its crystallization is carried out at the expense of C-A-S-H phase. The content of katoite hydrogarnet remains practically unchanged at the 5-6% level.
Figure 7. Correlation of lime-ash stone strength with its phase composition. 1 - Change in the intensity of the peak of aluminum substituted tobermorite according to the X-ray data; 2 - Change in content of aluminum substituted tobermorite according to the DTG data; 3 -Change in content of C-A-S-H according to the DTG data.
Figure 8. Correlation of lime-ash stone strength with its phase composition at addition of 1% Na2SO4. 4 - Change in the intensity of the peak of aluminum substituted tobermorite according to the X-ray data;
5 - change in content of aluminum substituted
tobermorite according to the DTG data;
6 - change in content of C-A-S-H according to the DTG data. Note: A - 8 hours of isothermal
exposure; x - 100 hours of isothermal exposure
Figure 9. Correlation of lime-ash stone strength with its phase composition at addition of 2% Na2SO4. 7 - Change in the intensity of the peak of aluminum substituted tobermorite according to the X-ray data; 8 - change in content of aluminum substituted tobermorite according to the DTG data; 9 - change in content of C-A-S-H according to the DTG data
The results obtained conforms with the most recent publications [5-7] reporting the formation of the phase composition in the autoclave stone basing on lime-quartz and cement-aluminosilicate compositions with additions of alumina or sulphate-containing materials.
Thus, the results obtained on the strength of the stone (Figure 1) are well explained by the findings of its phase composition. When there is no addition of sodium sulfate, the strength is proportional to the content of Al-tobermorite and gel C-A-S-H content. By adding of sodium sulfate, the rate crystallization of Al-tobermorite is increased and it replaces C-A-S-H phase. The more complete this substitution occurs, the less the strength of the stone. This can be explained by the high specific surface area of the particles of the solid phase of the C-A-S-H gel, which "glue" the composite. It is known that the specific surface area phase C-S-H is 250-300 m2/g.
However, the same rock strength is proportional to its density. Therefore, the larger the hydration products, the higher the density of the stone and greater its strength. For this reason, the strength of the stone through autoclaving 8 hours with admixture of sodium sulfate higher than without additives. Total weight loss of the composition without additives, after 8 hours of autoclaving was 8.7 % (Figure 3), and with the addition of sodium sulfate - 9.5% (Figure 5).
4. Conclusions
1. The strength of autoclaved stone based on lime and aluminosilicate ash of CHP increases in proportion to the duration of hydrothermal treatment. The amount of Al-tobomorite and the gel phase of C-A-S-H in the stone also increases in proportion. The hydrogarnet katoite plays a subordinate role and its quantity in the stone remains constant - 4-6 %.
2. Activation of hydrothermal synthesis in stone with the addition of Na2SO4 substantially redistributes the phase composition. The gel phase of C-A-S-H is significantly reduced by the crystallization of Al- tobermorite. The content of katoite remains constant. At the same time, it should be taken into account that when the hydration process is carried out, the C-A-S-H phase in tobermorite is activated, injected with alkaline sulphates, the total amount of hydrates is increased, which leads to the compaction of the stone increase its strength.
3. The strength of autoclave stone basing on aluminosilicate fly ash and lime is always proportional to the content of the C-A-S-H phase irrespectively to the content of tobermorite.
References
1. Kalousek, G.L., Adams, M. Tobermorite formation and strength of autoclave materials. Journal of the America concrete institute. 1951. No. 48. Pp. 77-81.
2. Crennan, G.M., El-Hemaly, S.A., Taylor, H.F.W. Autoclaved lime-quartz materials. Cement and Concrete Research. 1977. Vol. 7. Pp. 493-502.
3. Taylor, H.F.W. Cement Chemistry. Academic Press. London, 1990. 490 p.
4. Ray, A. Hydrothermally treated cement-based building materials. Past, present, and future. Pure Appl. Chem. 2002. Vol. 74. No. 11. Pp. 2131-2135.
5. Matsui, K., Kikuma, J., Tsunashima, M. In situ time-resolved X-ray diffraction of tobermorite formation in autoclaved aerated concrete: Influence of silica source reactivity and Al addition. Cement and Concrete Research. 2011. Vol. 41. No. I 5. Pp. 510-519.
Литература
1. Kalousek G.L., Adams M. Tobermorite formation and strength of autoclave materials // Journal of the America concrete institute. 1951. № 48. Pp. 77-81.
2. Crennan G.M., El-Hemaly S.A., Taylor H.F.W. Autoclaved lime-quartz materials // Cement and Concrete Research. 1977. Vol. 7. Pp. 493-502.
3. Taylor H.F.W. Cement Chemistry. Academic Press. London, 1990. 490 p.
4. Ray A. Hydrothermally treated cement-based building materials. Past, present, and future // Pure Appl. Chem. 2002. Vol. 74. № 11. Pp. 2131-2135.
5. Matsui К., Kikuma J., Tsunashima M. In situ time-resolved X-ray diffraction of tobermorite formation in autoclaved aerated concrete: Influence of silica source reactivity and Al addition // Cement and Concrete Research. 2011. Vol. 41. № I 5. Pp. 510-519.
6. Ríos, C.A., Williams, C.D., Fullen, M.A. Hydrothermal synthesis of hydrogarnet and tobermorite at 175 °C from kaolinite and metakaolinite in the CaO-Al2O3-SiO2-H2O system: A comparative study. Applied Clay Science. 2009. Vol. 43. Pp. 228-237.
7. Galvánková, L., Másilko, J., Solny, T., Stepánková, E. Tobermorite synthesis under hydrothermal conditions. Procedia Engineering. 2016. Vol. 151. Pp.100-107.
8. Komarneni, S., Roy, D.M. New tobermorite cation exchangers. Journal of material science. 1985. No. 20. Pp. 2930-2936.
9. Diamond, S., White, J.L., Dolch, W.L. Effects of isomorphous substitution in hydrothermally-synthesized tobermorite. American mineralogist. 1966. No. 51. Pp. 388-401.
10. Coleman, N.J., Brassington, D.S. Synthesis of Al-substituted 11A tobermorite from newsprint recycling residue: A feasibility study. Material research bulletin. 2003. No. 38. Pp. 485-497.
11. Coleman, N.J. Synthesis, structure and ion exchange properties of 11 A tobermorities from newsprint recycling residue. Material research bulletin. 2005. No. 40. Pp. 2000-2013.
12. Volodchenko, A.N., Vorontsov, V.M., Golikov, G.G. Vliyanie paragenezisa kvarts - glinistyie mineralyi na svoystva avtoklavnyih silikatnyih materialov [Influence of paragenesis of quartz - clay minerals on the properties of autoclave silicate materials]. Izvestiya vuzov. Stroitelstvo. 2000. No. 10. Pp. 57-60. (rus)
13. Loganina, V.I., Pyshkina, I.S., Martyashin, G.V. Influence of the additive on the basis of calcium hydrosilicates on the resistance of calcareous coatings Magazine of Civil Engineering. 2017. 72(4). Pp. 20-27.
14. Sirotyuk, V.V., Lunyov, A.A. Strength and deformation characteristics of the ash and slag mixture. Magazine of Civil Engineering. 2017. 74(6). Pp. 3-16.
15. Volodchenko, A.N., Lesovik, V.S. Silikatnyie avtoklavnyie materialyi s ispolzovaniem nanodispersnogo syirya [Silicate autoclave materials using nanodisperse raw materials]. Stroitelnyie materialyi. 2008. No. 11. Pp. 42-43. (rus)
16. Yamb, E., Chemu, Zh. Lesovik, V.S. Stroitelnyie materialyi na osnove lateritnyih porod Kameruna i tsementa [Construction materials based on lateritic rocks of Cameroon and cement]. Vestnik BGTU im. V.G. Shuhova. 2010. No. 1. Pp. 27-33. (rus)
17. Volodchenko, A.N. Osobennosti vzaimodeystviya magnezialnoy glinyi s gidroksidom kaltsiya pri sinteze novoobrazovaniy i formirovanie mikrostrukturyi [Features of the interaction of magnesian clay with calcium hydroxide in the synthesis of hydrates and the formation of a microstructure]. Vestnik BGTU im. V.G. Shuhova. 2011. No. 2. Pp. 51-55. (rus)
18. Volodchenko, A.N., Lesovik, V.S. Avtoklavnyie yacheistyie betonyi na osnove magnezialnyih glin [Autoclaved cellular concrete based on magnesian clays]. Izvestiya vuzov. Stroitelstvo. 2012. No. 5. Pp. 14-21. (rus)
19. Strokova, V.V., Nelyubova, V.V., Altyinnik, N.I., Zhernovskiy, I.V. Fazoobrazovanie v sisteme tsement-izvest-kremnezem v gidrotermalnyih usloviyah s ispolzovaniem nanostrukturirovannogo modifikatora [Phase formation in the cement-lime-silica system under hydrothermal conditions using a nanostructured modifier] Stroitelnyie materialyi. 2013. No. 9. Pp. 30-32. (rus)
20. Tunega, D., Zaoui, A. Understanding of bonding and mechanical characteristics of cementious mineral tobermorite from first principles. Journal of the European Ceramic Societ. 2012. Vol. 32. Pp. 306-314.
21. Richardson, I.G. The calcium silicate hydrates. Cement Concrete Res. 2008. Vol. 38. Pp. 137-158.
6. Ríos C.A., Williams C.D., Fullen M.A. Hydrothermal synthesis of hydrogarnet and tobermorite at 175 °C from kaolinite and metakaolinite in the CaO-Al2O3-SiO2-H2O system: A comparative study // Applied Clay Science. 2009. Vol. 43. Pp. 228-237.
7. Galvánková L., Másilko J., Solny T., Stepánková E. Tobermorite synthesis under hydrothermal conditions // Procedia Engineering. 2016. Vol. 151. Pp.100-107.
8. Komarneni S., Roy D.M. New tobermorite cation exchangers // Journal of material science. 1985. № 20. Pp. 2930-2936.
9. Diamond S., White J.L., Dolch W.L. Effects of isomorphous substitution in hydrothermally-synthesized tobermorite // American mineralogist. 1966. № 51. Pp. 388-401.
10. Coleman N.J., Brassington D.S. Synthesis of Al-substituted 11A tobermorite from newsprint recycling residue: A feasibility study // Material research bulletin. 2003. № 38. Pp.485-497.
11. Coleman N.J. Synthesis, structure and ion exchange properties of 11 A tobermorities from newsprint recycling residue // Material research bulletin. 2005. № 40. Pp. 2000-2013.
12. Володченко А.Н., Воронцов В.М., Голиков Г.Г. Влияние парагенезиса «кварц-глинистые минералы» на свойства автоклавных силикатных материалов // Известия ВУЗов. Строительство. 2000. № 10. С. 57-60.
13. Логанина В.И., Пышкина И.С., Мартяшин Г.В. Влияние добавки на основе гидросиликатов кальция на стойкость известковых покрытий // Инженерно-строительный журнал. 2017. № 4(72). С. 20-27.
14. Сиротюк В.В., Лунёв А.А. Прочностные и деформационные характеристики золошлаковой смеси // Инженерно-строительный журнал. 2017. № 6(74). С. 3-16.
15. Володченко А.Н., Лесовик В.С. Силикатные автоклавные материалы с использованием нанодисперсного сырья // Строительные материалы. 2008. № 11. С. 42-43.
16. Ямб Э., Чему Ж., Лесовик В.С., Володченко А.Н. Строительные материалы на основе латеритных пород Камеруна и цемента // Вестник БГТУ им. В.Г. Шухова. 2010. № 1. С. 27-33.
17. Володченко А.Н. Особенности взаимодействия магнезиальной глины с гидроксидом кальция при синтезе новообразований иформирование микроструктуры // Вестник БГТУ им. В.Г. Шухова. 2011. № 2. С. 51-55.
18. Володченко А.Н., Лесовик В.С. Автоклавные ячеистые бетоны на основе магнезиальных глин // Известия ВУЗов. Строительство. 2012. № 5. Pp. 14-21.
19. Строкова В.В., Нелюбова В.В., Алтынник Н.И., Осадчий Е.Г. Фазообразование в системе цемент-известь-кремнезем в гидротер мальных условиях с использованием наноструктурированного модификатора // Строительные материа лы. 2013. № 9. С. 30-32.
20. Tunega D., Zaoui A. Understanding of bonding and mechanical characteristics of cementious mineral tobermorite from first principles // Journal of the European Ceramic Societ. 2012. Vol. 32. Pp. 306-314.
21. Richardson I.G. The calcium silicate hydrates // Cement Concrete Res. 2008. Vol. 38. Pp. 137-158.
22. Biagioni C., Merlino S., Bonaccorsi E., The tobermorite supergroup: a new nomenclature // Mineral. Mag. 2015. Vol. 79. Pp. 485-495.
23. Maeda H., Abe K., Ishida E.H. Hydrothermal synthesis of aluminium substituted tobermorite by using various crystal phases of alumina // J. Ceram. Soc. Jpn. 2011. Vol. 119 Pp. 375-377.
22. Biagioni, C., Merlino, S., Bonaccorsi, E. The tobermorite supergroup: a new No.menclature. Mineral. Mag. 2015. Vol. 79. Pp. 485-495.
23. Maeda, H., Abe, K., Ishida, E.H. Hydrothermal synthesis of aluminium substituted tobermorite by using various crystal phases of alumina. J. Ceram. Soc. Jpn. 2011. Vol. 119. Pp. 375-377.
24. Coleman, N.J., Trice, C.J., Nicholson, J.W. 11 A tobermorite from cement bypass dust and waste container glass: A feasibility study. Int. J. Miner. Process. 2009. Vol. 93. Pp. 73-78.
25. Tsutsumi, T., Nishimoto, S., Kameschima, Y. Hydrothermal preparation of tobermorite from blast furnace slag for Cs+ anr Sr2+ sorption. J. Hazard. Mater. 2014. Vol. 266. Pp. 174-181.
26. Mostafa, N.Y., Shaltout, A.A., Omar, H. Hydrothermal synthesis and characterization of aluminium and sulfate susbstituted 1.1 nm tobermorities. J. Alloys Compd. 2009. Vol. 467. Pp. 332-337.
27. Kikuma, J., Tsunashima, M., Ishikawa, T. Effect of quartz particle size and water-to-solid ratio on hydrothermal synthesis of tobermorite studied by in-situ time-resolved X-ray diffraction. J. Solid State Chem. 2011. Vol. 184. Pp. 2066-2074.
28. Jackson, M.D., Moon, J., Gotti, E. Material and Elastic Properties of Al-Tobermorite in Ancient Roman Seawater Concrete. Journal of the American Ceramic Society. 2013, Vol. 96. No. 8. Pp. 2598
29. Ilyukhin, V.V., Kuznetsov, V.A., Lobachev, A.N. Gidrosilikaty kalciya. Sintez monokristallov I kristallohimiya. [Calcium hydrosilicates. Synthesis of single crystals and crystal chemistry]. Moscow: Nauka, 1979. 184 p. (rus).
30. Churakov, S.V. Structural position of H2O molecules and hydrogen bonding in anomalous 11 A tobermorite. American Mineralogist. 2009. Vol. 94. Pp. 156-165.
31. Grangeon, S., Claret, F., Lerouge, C. On the nature of structural disorder in calcium silicate hydrates with a calcium/silicon ratio similar to tobermorite. Cement and Concrete Research. 2013. Vol. 52. Pp. 31-37.
32. Youssef, H., Ibrahim, D., Komarneni, S. Synthesis of 11 A Al-substituted tobermorite from trachyte rock by hydrothermal treatment. Ceramics International. 2010. No. 36. Pp. 203-209.
33. Miyake, M., Komarneni, S., Roy, R. Kinetics, Equilibria and Thermodynamics of Ion Exchange in Substituted Tobermorites. Material research bulletin. 1989. No. 24. Pp. 311-320.
34. Nocun-Wezelik, W. Effect of Na and Al on the phase composition and morphology of autoclaved calcium silicate hydrates. Cement Concrete Res. 1999. Vol. 29. Pp. 1759-1767.
35. Reinik, J., Heinmaa, I., Mikkola, J.-P. Hydrothermal alkaline treatment of oil shale ash for synthesis of Tobermorites. Fuel. 2007. No. 86. Pp. 669-676.
36. Huang, X., Jiang, Tan S. Tobermorites synthesiz from newsprint recycling residue. Journal of the European Ceramic Societ. 2003. No. 23. Pp. 123-126.
37. Komarneni, S., Komarneni, J.S., Newalkar, B. Microwave-hidrothermal synthesis of Al-substituted tobermorite from zeolites. Material research bulletin. 2002. Vol. 37. No. 6. Pp. 1025.
Gennady Ovcharenko*, +7(905)928-11-90; egogol980@mail. ru
Danil Gilmiyarov,
+7(905)928-11-90; egogol980@mail.ru
24. Coleman N.J., Trice C.J., Nicholson J.W. 11 A tobermorite from cement bypass dust and waste container glass: A feasibility study // Int. J. Miner. Process. 2009. Vol. 93. Pp. 73-78.
25. Tsutsumi T., Nishimoto S., Kameschima Y. Hydrothermal preparation of tobermorite from blast furnace slag for Cs+ anr Sr2+ sorption // J. Hazard. Mater. 2014. Vol. 266. Pp. 174-181.
26. Mostafa N.Y., Shaltout A.A., Omar H. Hydrothermal synthesis and characterization of aluminium and sulfate susbstituted 1.1 nm tobermorities // J. Alloys Compd. 2009. Vol. 467. Pp. 332-337.
27. Kikuma J., Tsunashima M., Ishikawa T. Effect of quartz particle size and water-to-solid ratio on hydrothermal synthesis of tobermorite studied by in-situ time-resolved X-ray diffraction // J. Solid State Chem. 2011. Vol. 184. Pp. 2066-2074.
28. Jackson M.D., Moon J., Gotti E. Material and Elastic Properties of Al-Tobermorite in Ancient Roman Seawater Concrete // Journal of the American Ceramic Society. 2013. Vol. 96. № 8. Pp. 2598
29. Илюхин В.В., Кузнецов В.А., Лобачёв А.Н., Бакшутов B.C. Гидросиликатыкальция. Синтез монокристаллов и кристаллохимия. М: Наука, 1979. 184 с.
30. Churakov S.V. Structural position of H2O molecules and hydrogen bonding in anomalous 11 A tobermorite // American Mineralogist. 2009. Vol. 94. Pp. 156-165.
31. Grangeon S., Claret F., Lerouge C. On the nature of structural disorder in calcium silicate hydrates with a calcium/silicon ratio similar to tobermorite // Cement and Concrete Research. 2013. Vol. 52. Pp. 31-37.
32. Youssef H., Ibrahim D., Komarneni S. Synthesis of 11 A Al-substituted tobermorite from trachyte rock by hydrothermal treatment // Ceramics International. 2010. № 36. Pp. 203-209.
33. Miyake M., Komarneni S., Roy R. Kinetics, Equilibria and Thermodynamics of Ion Exchange in Substituted Tobermorites // Material research bulletin. 1989. № 24. Pp. 311-320.
34. Nocun-Wezelik W. Effect of Na and Al on the phase composition and morphology of autoclaved calcium silicate hydrates // Cement Concrete Res. 1999. Vol. 29. Pp. 1759-1767.
35. Reinik J., Heinmaa I., Mikkola J.-P. Hydrothermal alkaline treatment of oil shale ash for synthesis of Tobermorites // Fuel. 2007. № 86. Pp. 669-676.
36. Huang X., Jiang, Tan S. Tobermorites synthesiz from newsprint recycling residue // Journal of the European Ceramic Societ. 2003. № 23. Pp. 123-126.
37. Komarneni S., Komarneni J.S., Newalkar B. Microwave-hidrothermal synthesis of Al-substituted tobermorite from zeolites // Material research bulletin. 2002. Vol. 37. № 6. Pp. 1025.
Гзннадии Иванович Овчаренко*,
+7(905)928-11-90;
эл. почта: egogo1980@mail.ru
Данил Игоревич Гильмияров,
+7(905)928-11-90;
эл. почта: egogo1980@mail.ru
© Ovcharenko, G.I., Gilmiyarov, D.I., 2018
