RU2211194C1 - Expansion additive, hydraulic binder with indicated additive, and a method for preparation thereof - Google Patents

Abstract

FIELD: manufacture of building materials. SUBSTANCE: expansion additive based on sulfoaluminate clinker for manufacturing nonshrinking or expanding products when added to hydraulic binder, which includes Portland cement and/or its modifications, comprise sulfoaluminate clinker composed, wt %: low- basicity calcium sulfoaluminate (4CaO•3Al₂O₃•SO₃) 20-65, high-basicity calcium sulfoaluminate ((7-9)CaO•(2-3)Al₂O₃•2SO₃,) 15-30, dicalcium silicate ((1,8-2,3)CaO•SiO₂,) 0.5-55, monocalcium aluminate (CaO•Al₂O₃) 1-5, anhydrite (CaSO₄) 3- 10, impurities - the balance, and, additionally, an aromatic acid (in particular benzoic acid) and a higher fatty acid at weight ratio of indicated mineral components to acids 1:(0.025-0.3):(0.02-0.2), said higher fatty acid being stearic or oleic acid, or their 1:5 to 5:1 w/w mixtures. Acids contained in expansion additive are present in the form of solutions and/or melts. Hydraulic binder is a product of joint or separate (with subsequent mixing) grinding of matrix ingredient and expansion additive, said matrix ingredient being Portland cement and/or its modifications: products of joint or separate (with subsequent mixing) grinding of Portland cement clinker and gypsum stone at weight ratio of Portland cement clinker, gypsum stone (calculated for SO₃), and expansion additive 100:(2-4):(1.5-4). Sulfoaluminate clinker is fired to caking in reductive medium at temperatures allowing content of tricalcium silicate 0.5-3% and that of content of mayenite and/or its halide or sulfide derivatives 0.3-2%. Grinding is effected until homogenously distributed waterproofed film of expanding phase appears on binder particles when being formed. The latter is determined with regard to criterion of formation after tempering of resulting product with water of globular mass homogenized by stirring and rubbing to give homogenous binding water suspension. EFFECT: reduced expenses and increased storage time of nonshrinking or expanding Portland cement. 7 cl, 3 tbl, 3 ex

Description

 The invention relates to the field of building materials and products, namely, expanding additives for the manufacture of non-shrinking or expanding products, hydraulic binders with these additives and methods for manufacturing such binders.

 It is known that cement-water systems at the end of setting, when marks can be fixed in them and the distance between them is measured, begin to shrink, that is, volumetric deformation of a reduction in geometric dimensions, lasting up to five years. More than half of it falls on the first day, and if the labels are inserted later, then the first part of shrinkage deformations is not noted at all. The characteristic values of linear shrinkage, that is, shrinkage, measured in one of the directions, usually along the long side of the sample hardening cement-water systems, for 24 h - 1 year for certain types of hardened cement-water systems are as follows: for cement stone (hardened cement test normal density) - up to 3 mm / m, for mortar, including cement, sand and water: with the ratio of ingredients (by weight) cement: sand: water 1: 1: 0.35 - up to 1.5 mm / m, s with a ratio of 1: 3: 0.4 - up to 0.8 mm / m, and for concrete with a ratio of ingredients (according to mass) cement: sand: crushed stone: water 1: 2: 4: 0.5 - up to 0.15 mm / m. Further, shrinkage usually fades in time according to the logarithmic law. V. Michaelis in 1905 explained the shrinkage and its attenuation by the fact that the main hydrates of Portland cement and / or its varieties - gels - undergo a decrease in volume during syneresis, i.e. water separation, including as a result of its suction as under the influence of capillary forces with subsequent evaporation (physical shrinkage), and under the influence of chemical reactions of water binding by residues of particles of the original cement (chemical shrinkage). These names of types of shrinkage were introduced by T. Powers in 1947. C. Pickett in 1957 estimated the proportions of each type of shrinkage in these cement-water systems at different water-cement ratios (W / C) and came to the conclusion that with W / C 0.3 - 0.6 they are of the same order of magnitude, moreover, at lower H / C values, the share of chemical shrinkage is more than 60% of the total volumetric strain, and for large values, the share of physical shrinkage is more than 60% of the indicated total value [1]. Shrink joints in concrete structures and constructions, proposed in France in 1871 to prevent crack formation from shrinkage deformations, complicate concrete work, therefore cement that is not subject to shrinkage, for example, expanding or at least non-shrink, it is advisable to produce and apply at least for simplification of concreting of structures and structures. It is also obvious that these cements prevent cracking from deformations associated with the physical and chemical shrinkage of cement stone both on the surface of products and structures, mortars, facade layers and plasters, and inside concrete and reinforced concrete masses, thereby ensuring the solidity of building products, parts and structures and making it difficult for water and other aggressive environmental agents to access the volumes of these materials, also called cement products. In addition, non-shrinking and expanding cements provide protection against contact of these agents with steel reinforcement in reinforced cement and reinforced concrete, blocking channels and pores at the boundaries of reinforcement and concrete. All this increases the durability of building and architectural elements made of cement stone and mortar, as well as reinforced cement, concrete and reinforced concrete products, structures, buildings and structures.

 Non-shrinking and expanding cements have been known for about 180 years, taking into account that the cement proposed by E. Cheliev in Russia in 1821, judging by its chemical composition, published according to the chemical analysis performed on the preserved sample of I. B. Znachko - Yavorsky in 1955, was sulfoaluminate and, therefore, expanding. The first in the XX century information on cement expanding during hardening after water hardening, obtained by introducing an expanding additive into Portland cement, with data on the results of measurements of strains of the initial expansion of the hardening product and its subsequent shrinkage, was published by A. Lossier (France [2]). As non-shrinking or expanding products, he obtained a hardening cement-water slurry, or cement stone, a hardening mortar obtained by mixing a mixture of expanding cement and sand with water, and concrete obtained by mixing a mixture of the specified cement, fine aggregate (sand) and coarse aggregate with water (crushed stone or gravel). Moreover, their initial expansion was either approximately equal to the subsequent shrinkage (for non-shrinking products) or exceeded the subsequent shrinkage (for expanding products).

; здесь и ниже используется сокращенная нотация химических соединений и минералов, общепринятая в химии цемента: Аl₂O₃ = А, СаО = С, Fе₂О₃ = F, H₂O = Н, К₂О = К, MgO = M, Na₂O = N, SiO₂ = S,

, сульфидная сера

). Кроме того, в составе этого клинкера она установила присутствие следующих составляющих: двухкальциевого силиката (белита, C₂S), майенита (C₁₂A₇) и ангидрита

. Однако Лоссье не сумел обнаружить указанного сульфоалюмината кальция, поэтому регулировать минералогический состав такой добавки для него было затруднительно. Исходя из этого, и содержание указанной добавки на основе САК в составе безусадочного цемента Лоссье принимал с запасом: в указанной публикации содержание добавки в цементе для расширяющихся продуктов составляло подчас 20% и более, а для безусадочных - не менее 16%. В этой связи полученный Лоссье расширяющийся цемент не мог быть назван расширяющимся портландцементом, поскольку по определению, содержащемуся во французском стандарте того времени, портландцемент мог включать не более 5 мас.% посторонних добавок.As an expanding additive in an expanding or non-shrink cement, Lossier took a sulfoaluminate clinker (NAO), obtained by firing before sintering at 1250-1300 ^o With a mixture of limestone, bauxite and gypsum. The mineralogical composition of such a clinker, as T.A. showed Ragosin, 20 years later [3], included a new component discovered by her - calcium sulfoaluminate with a gross formula of 4 CaO • 3Al ₂ O ₃ • SO ₃ (abbreviated as

; here and below, the abbreviated notation of chemical compounds and minerals is generally accepted in cement chemistry: Al ₂ O ₃ = A, CaO = C, Fe ₂ O ₃ = F, H ₂ O = H, K ₂ O = K, MgO = M, Na ₂ O = N, SiO ₂ = S,

sulfide sulfur

) In addition, as part of this clinker, she established the presence of the following components: dicalcium silicate (belite, C ₂ S), mayenite (C ₁₂ A ₇ ) and anhydrite

. However, Lossier failed to detect the specified calcium sulfoaluminate, therefore, it was difficult for him to regulate the mineralogical composition of such an additive. Proceeding from this, Lossier accepted the content of the indicated additive based on NAO in the composition of non-shrinkable cement: in this publication, the content of the additive in cement for expanding products was sometimes 20% or more, and for non-shrinkable materials - at least 16%. In this regard, Lossier obtained expanding cement could not be called expanding Portland cement, since, by definition, contained in the French standard of that time, Portland cement could include no more than 5 wt.% Foreign additives.

в воде затворения цементных продуктов требуются дополнительные количества сульфата кальция, а также оксид кальция. Источниками первого является ангидрит - один из компонентов САК - в дополнение к гипсовому ингредиенту цемента. Оксид кальция в гидратной форме получается в результате гидролиза алита (C₃S) - основного минерала портландцементного клинкера - водой затворения. Таким образом, для расширения требуется взаимодействие в жидкой фазе указанных цементных продуктов четырех реагентов: сульфоалюмината кальция и ангидрита из САК добавки, алита из клинкерного и сульфата кальция - из гипсового компонентов матричного ингредиента вяжущего. Встреча четырех реагентов в жидкой фазе цементо-водной системы, протекающая с диффузионным контролем и в этой связи зависящая от содержания воды в твердеющей цементо-водной системе, предопределяет медленное течение синтеза трисульфата и соответственно - процесса расширения цементных продуктов и его зависимость от В/Ц. Это вносит неопределенность, как в процесс расширения, так и в потребное содержание расширяющей добавки в составе расширяющего или безусадочного цемента. Однако главную долю неопределенности в процесс расширения цемента, включающего добавку САК, по Лоссье, вносит минерал майенит (C₁₂A₇), входящий в состав добавки Лоссье. Причина состоит в том, что этот минерал при гидратации проходит стадию разделения продуктов по основности, образуя, с одной стороны, низкоосновный, т.е. вовсе не содержащий кальция гидрогель глинозема состава Аl(ОН)₃ и/или АlO(ОН), в целом сокращенно обозначаемый А - Н (G) (здесь тире - знак неполноты определенности состава фазы, G - гель), а с другой стороны - наиболее высокоосновную из известных гидроалюминатных фаз - фазу Ассарсона - Флинта - Уэллса (АФУ) С₆АН₃₆ (состав этой фазы приводится по данным работ 90-х годов - Пюльмана с сотр. ). Вследствие активного поглощения указанными продуктами гидратации С₁₂А₇ соответственно воды - гидрогелем А-Н (G), а также воды и извести в гидратной форме - фазой С₆АН₃₆, в жидкой фазе цементо-водной системы возникает недостаток свободной воды и извести, препятствующий образованию упомянутого трисульфата и расширению цемента. Фаза АФУ существует примерно около 20 минут, после чего распадается на гидроалюминаты кальция С₄АН_13-19 и C₂AH_8-11 а также гидроксид кальция СН. Эти гидроалюминаты дополнительно осушают указанную систему при своем образовании. Кроме того, указанный гидрогель препятствует упомянутой выше реакции между тремя реагентами, существенно усиливая диффузионный барьер. Поэтому в присутствии C₁₂A₇, особенно при его максимальном количестве (по оценке А. Лафюма, анализировавшего в 1938 г. САК, изготовленный Лоссье, содержание этого минерала в нем колебалось в пределах от 5 до 15 мас. %), эффективность добавки Лоссье как расширяющего агента существенно снижалась, и именно в присутствии майенита требовалось вводить добавку Лоссье в расширяющийся цемент в повышенном количестве, а именно до 20% и более. Этим обусловлена неопределенность свойств расширяющейся добавки Лоссье: заранее, то есть до завершения обжига до спекания данной партии сульфоалюминатного клинкера по Лоссье, было невозможно предсказать расширяющиеся свойства его добавки, а после обжига требовалось непременно производить прикидочные эксперименты, чтобы определить, в каких количествах эту добавку следует вводить в цемент для достижения безусадочности, а в каких - для достижения расширения цемента. Тем не менее, в любых случаях уже отсутствие усадки и тем более - расширение цемента повышает степень водонепроницаемости цементных продуктов.According to Lossier, the mechanism of expansion of cement with an additive based on NAO is reduced to crystallization of a higher content of calcium hydrosulfoaluminate phase in hydrated neoplasms compared to conventional Portland cement, now briefly called "trisulfate"; this phase was discovered as part of hydrated neoplasms of ordinary Portland cement by Eugene Canddo (1892); it is described in more detail below. Its expanding effect is due to the fouling of rapidly growing high-water trisulfate crystals of the main calcium-silicate gel-crystalline aggregate of the hardening cement-water system, the strength of which provides all the basic technical properties of cement. This intergrowth is called the matrix of this system in modern scientific and technical literature, and the Portland cement clinker ingredient, which provides strength, is called matrix [4]. For the synthesis of the specified trisulfate from

in the mixing water of cement products, additional quantities of calcium sulfate are required, as well as calcium oxide. The sources of the first are anhydrite - one of the components of NAO - in addition to the gypsum cement ingredient. Calcium oxide in hydrated form is obtained by hydrolysis of alite (C ₃ S) - the main mineral of Portland cement clinker - mixing water. Thus, expansion requires the interaction in the liquid phase of these cement products of four reagents: calcium sulfoaluminate and anhydrite from NAO additives, alite from clinker and calcium sulfate from gypsum components of the matrix binder ingredient. The meeting of the four reagents in the liquid phase of the cement-water system, proceeding with diffusion control and in this regard, depending on the water content in the hardening cement-water system, determines the slow synthesis of trisulfate and, accordingly, the process of expansion of cement products and its dependence on W / C. This introduces uncertainty both in the expansion process and in the required content of the expanding additive as part of the expanding or non-shrinking cement. However, according to Lossier, the main share of uncertainty in the process of cement expansion, including the addition of NAO, is made by the mineral mayenite (C ₁₂ A ₇ ), which is part of the Lossier additive. The reason is that, when hydrated, this mineral goes through the stage of separation of products in basicity, forming, on the one hand, low basic, i.e. completely calcium-free alumina hydrogel of composition Al (OH) ₃ and / or AlO (OH), generally abbreviated as A - H (G) (here the dash is the sign of incompleteness of the phase composition, G is the gel), and on the other hand, the most basic of the known hydroaluminate phases is the Assarson – Flint – Wells phase (AFU) C ₆ AN ₃₆ (the composition of this phase is given according to the data of the 90s — Pulman et al.). Due to the active absorption by these hydration products of C ₁₂ A _7, respectively, of water — AH (hydrogel) hydrogel, as well as water and lime in hydrated form — by phase C ₆ AN ₃₆ , a lack of free water and lime occurs in the liquid phase of the cement-water system, preventing the formation of said trisulfate and expansion of cement. The AFU phase exists for about 20 minutes, after which it decomposes into calcium hydroaluminates C ₄ AN _13-19 and C ₂ AH _8-11 as well as calcium hydroxide CH. These hydroaluminates additionally drain the specified system during its formation. In addition, this hydrogel inhibits the aforementioned reaction between the three reagents, significantly enhancing the diffusion barrier. Therefore, in the presence of C ₁₂ A ₇ , especially at its maximum amount (according to A. Lafum, who analyzed Lossier in 1938, the content of this mineral in it ranged from 5 to 15 wt.%), The effectiveness of the Lossier additive as an expanding agent, it was significantly reduced, and it was in the presence of Mayenite that Lossier's additive was required to be added to expanding cement in an increased amount, namely, up to 20% or more. This determines the uncertainty of the properties of the expanding Lossier additive: in advance, that is, until the firing was completed before sintering the batch of sulfoaluminate clinker according to Lossier, it was impossible to predict the expanding properties of its additive, and after firing, it was imperative to carry out preliminary experiments to determine in what quantities this additive should be injected into cement to achieve non-shrinkage, and in which to achieve expansion of cement. Nevertheless, in any cases, the absence of shrinkage, and even more so, the expansion of cement increases the degree of waterproofing of cement products.

Also known is an expanding additive for the manufacture of non-shrinking or expanding products when it is introduced into cement, including the natural mineral alunite [KAL ₃ (SO ₄ ) ₂ (OH) ₆ ]. When it is added to the cement composition in a calcined state (after dehydration at 650 - 800 ^o С) in an amount of 10%, Portland cement acquires the property of only faster hardening in the early stages, but does not become non-shrink (F.L. Gleckel, 1947), and only with its introduction in the amount of 18-20% (KS Kutateladze, T. G. Gabadadze, 1955 - 1965), non-shrinking and expanding cements can be obtained [5]. In a recent review on alunite, it was shown that with an increased gypsum content and the introduction of high aluminate pozzolana in cement, it is possible to expand cement, including unburnt alunite [6]. The disadvantage of the calcined alunite additive is also associated with the uncertainty of the composition of the calcined product, since the rate of interaction in the mixing water of the calcined alunite additive with the products of hydration of calcium aluminates from the matrix ingredient of expanding or non-shrink cement and with hydrolytic lime from alite, also contained in the specified cement, and, finally, with gypsum stone from the composition of the specified cement, significantly depends on the residual content of hydroxyls and potassium in the product of firing alunite ore. The disadvantage of the additive from unfired alunite is the inconsistency in the composition, speed and completeness of the release of anions, including Al ₂ O ₃ , into the liquid phase of the cement-water suspension. Moreover, it is known, in particular, that only about half of Al ₂ O ₃ entering the indicated liquid phase enters the expanding phase, namely, trisulfate, and the rest of it - into aluminosilicate gels that do not affect the expansion. In both cases, stabilize the manufacturing process of expanding alunite cements so that changes in the alunite content in the initial ore, the amount of impurities in the alunite mineral and the particle size distribution of the crushed product of the crushing of the original ore or the grinding product of raw alunite in cement, as well as fluctuations in the firing regime and solubility of products roasting and grinding did not affect the constancy of the composition and properties of the finished additive, failed.

Also known is an expanding additive based on sulfoaluminate clinker for the manufacture of non-shrinking or expanding products when it is introduced into Portland cement and / or its varieties, including components: mineral: sulfoaluminate clinker (SAK); organic: aromatic acid and higher fatty acid introduced into Portland cement and / or its varieties in an amount of 5 to 10% by weight of the clinker ingredient [7]. The physicochemical meaning of this technical solution consists in the surface dissolution of calcium sulfoaluminate from NAO upon contact of the latter with aromatic acid to form a complex compound of an aluminum ion with aromatic hydrocarbon radicals, which can exist only under conditions of protection against atmospheric moisture and carbon dioxide due to the insulation created by the presence of higher fatty acid. However, this idea, by the way, which is absent in the work [7], which is purely empirical, is completely depreciated by the uncontrolled presence of mayenite (C ₁₂ A ₇ ) or its halide derivatives in the NAO composition. The latter, due to the superstoichiometric excess of oxygen atoms in them (more than 0.3%) and correspondingly extremely high concentration of cationic vacancies (A. Jivartnam, 1971) chemisorb these organic components of the expanding additive chemically during the course of quick side reactions almost before their interaction with sulfoaluminate calcium. Therefore, this additive, as shown by testing experiments of the authors of the present invention, is effective only when the content of 5-15% of the mass of the clinker ingredient is present, and only its maximum content in the specified range ensures shrinkage or expansion of the resulting product, regardless of the quality of the matrix binder ingredient.

, или моноалюминат кальция СА, или майенит С₁₂А₇ или смесь указанных минералов с мольным отношением С/А менее 3, а также сульфат кальция в форме ангидрита

или гипса С•SH₂ в массовом соотношении с сульфоалюминатом или алюминатом кальция примерно 1 : 2, и органический - любой жидкий гидрофобизатор, в том числе жирную кислоту [31], при следующем содержании указанных компонентов (% от веса цемента):
Минеральный компонент - 9 - 60
Органический компонент - 0,1- 1,5
Высокое содержание этой добавки в смеси с вяжущим, повышенная стоимость готового расширяющего или безусадочного цемента и пониженное количество последнего из единицы массы указанной добавки - главные недостатки технического решения согласно прототипу.Closest to the proposed invention in terms of expanding additives (prototype) is an expanding additive containing components: mineral: calcium sulfoaluminate

or calcium monoaluminate CA, or C ₁₂ A ₇ mayenite or a mixture of these minerals with a C / A molar ratio of less than 3, as well as calcium sulfate in the form of anhydrite

or gypsum С • SH ₂ in a mass ratio with calcium sulfoaluminate or calcium aluminate is about 1: 2, and organic - any liquid hydrophobizing agent, including fatty acid [31], with the following content of these components (% by weight of cement):
Mineral component - 9 - 60
Organic component - 0.1-1.5
The high content of this additive in a mixture with a binder, the increased cost of the finished expansion or non-shrink cement, and the reduced amount of the last of a unit mass of the specified additive are the main disadvantages of the technical solution according to the prototype.

 The objective of the invention is to remedy these disadvantages by achieving a significantly lower content of expanding additives in the finished product compared to the prototype by releasing the expanding phase in the hardening water-binder system from side reactions.

This problem is solved in that in an expanding additive based on sulfoaluminate clinker for the manufacture of non-shrinking or expanding products when introduced into a hydraulic binder, including a matrix ingredient, namely Portland cement and / or its varieties, mineral - sulfoaluminate clinker and organic - fatty acid, organic the component contains fatty acid - higher and additionally - aromatic acid, and sulfoaluminate clinker has a composition, wt.%:
Low basic calcium sulfoaluminate - 20 - 65
Highly basic calcium sulfoaluminate - 15 - 30
Dicalcium silicate - 0.5-55
Monocalcium Aluminate - 1-5
Anhydrite - 3 - 10
Impurities - Rest
at wt. the ratio in the composition of the specified additives specified mineral component and each of these acids in the organic component 1: 0.025 - 0.3: 0.02 - 0.2, respectively.

In an embodiment of the invention, the expanding additive as a low basic calcium sulfoaluminate includes a mineral with a gross formula of 4 CaO • 3Al ₂ O ₃ • SO ₃ , and as a highly basic calcium sulfoaluminate a mineral with a gross formula of (7-9) CaO • (2-3) Al ₂ O ₃ • 2SO ₃ , as a dicalcium silicate - a mineral with a gross formula (1.8 - 2.3) CaO • SiO ₂ , as monocalcium aluminate - a mineral with a gross formula CaO • Al ₂ O ₃ and as anhydrite - a mineral with gross formula of CaSO ₄ .

 In another embodiment of the invention, as aromatic acid, it contains benzoic acid, and as the highest fatty acid, stearic acid or oleic acid, or a mixture of the latter in wt. a ratio of 1: 5 to 5: 1, respectively.

 In a further embodiment of the invention, the expanding additive contains said acids in the form of their solutions and / or melts.

The essence of the invention in terms of expanding additives is that in the composition of the NAO according to the invention, obtained by firing before sintering in a reducing medium, there is no mayenite (C ₁₂ A ₇ ), provided that the chemical composition of the raw mix for NAO is taken with excess lime to form when roasting highly basic calcium sulfoaluminate and completing the calcination in the period from formation to complete decomposition of the latter. Such a new type of ASA with highly basic calcium sulfoaluminate and in the practical absence of mayenite and free calcium oxide was first experimentally obtained by the authors of the present invention. When using such an ASA as part of the specified additive, side reactions of the organic components of the specified additive with mayenite and / or its derivatives are eliminated, and the organic components of the additive are completely consumed for the above complex compounds of aluminum ion and their protection from the environment. This is what allows you to radically reduce the required amount of expanding additives to give the specified cement shrinkage or expansion compared with similar additives known in the prior art.

и называется эттрингитом - от местечка Эттринген в Германии, где данный минерал впервые обнаружен в природе). Этот гидросульфоалюминат кальция образуется также и в жидкой фазе водной суспензии обыкновенного портландцемента в результате реакции между трехкальциевым алюминатом (С₃А) из клинкерного ингредиента и гипсовым камнем (

). В этом случае он содержит различные примеси и называется кратко "трисульфат", поскольку его валовая формула включает три молекулы сульфата кальция. При гидратации обыкновенного портландцемента трисульфат формируется сначала в виде геля, как показано А. Эмануэльсон с сотр. [8] в 1997 г., а затем кристаллизуется в виде столбчатых волокон трубчатого строения, образующих сростки. Обычно такой трисульфат снижает усадочные деформации цементо-водных систем, но лишь образующийся при гидратации САК трисульфат сразу образует микрокристаллы, которые растут до крупных размеров - 10 - 50 мкм, что и приводит к расширению. Для трисульфата, полученного в результате взаимодействия в жидкой фазе продуктов гидратации глиноземистого цемента, гипса и извести, это установлено в работе [9]. Когда гетерогенная реакция образования трисульфата заканчивается в результате исчерпания ингредиентов, для которых доступен взаимный контакт в жидкой фазе, цементный камень, строительный раствор или бетон благодаря начальной матрице - первичному скелету на основе сростка кристаллов трисульфата - характеризуется меньшей усадкой или расширением по сравнению с аналогичными материалами без указанной добавки, и эти изменения деформативных свойств указанных материалов являются необратимыми.In this case, an expanding additive containing the indicated calcium sulfoaluminates in the presence of hydrolytic lime secreted by alit (C ₃ S) of Portland cement clinker from the binder during its hydrolysis into the liquid phase of the cement-water system, and in the presence of additional amounts of sulfur trioxide (in addition to the NAO) in the indicated liquid phase, from the soluble impurities in the Portland cement clinker and from the gypsum stone of the specified binder, an additional amount of the AFt phase is synthesized, namely the trisulfate form of hydrosulfoalumin ata calcium abbreviated - thiosulphate (pure, free of impurities of iron and other species of this mineral has gross formula 3SaO • Al ₂ O ₃ • 3CaSO ₄ • 32H ₂ O, or, in abbreviated notation adopted in cement chemistry -

and is called ettringite - from the town of Ettringen in Germany, where this mineral was first discovered in nature). This calcium hydrosulfoaluminate is also formed in the liquid phase of an aqueous suspension of ordinary Portland cement as a result of the reaction between tricalcium aluminate (C ₃ A) from the clinker ingredient and gypsum stone (

) In this case, it contains various impurities and is briefly called “trisulfate”, since its gross formula includes three molecules of calcium sulfate. During the hydration of ordinary Portland cement, trisulfate is first formed in the form of a gel, as shown by A. Emanuelson et al. [8] in 1997, and then crystallizes in the form of columnar fibers of a tubular structure, forming splices. Typically, such trisulfate reduces the shrinkage deformation of cement-water systems, but only trisulfate formed during hydration of NAO immediately forms microcrystals, which grow to large sizes - 10 - 50 microns, which leads to expansion. For trisulfate obtained as a result of interaction in the liquid phase of the hydration products of aluminous cement, gypsum and lime, this was established in [9]. When the heterogeneous trisulfate formation reaction ends as a result of the exhaustion of ingredients for which mutual contact in the liquid phase is available, cement stone, mortar or concrete, thanks to the initial matrix - the primary skeleton based on the aggregate of trisulfate crystals - is characterized by less shrinkage or expansion compared to similar materials without the specified additives, and these changes in the deformation properties of these materials are irreversible.

In an embodiment of the invention, it is taken into account that the components of the NAO are not, when fired, minerals with constant stoichiometry. Almost basic in composition, a low basic sulfoaluminate and calcium sulfate are always formed. The remaining components are characterized by inconstancy of stoichiometry, although with the accumulated experience of firing, this does not prevent the solution of the main task of the invention — obtaining a no-charge MAS. The advantage of the non-stoichiometric composition of the components of the NAO is that in this case the trisulfate formed in the liquid phase of the cement-water system contains more impurities, mainly silicate ions (SiO ₄ ^4- , etc.), which strengthens the aggregation of cement stone based on it and facilitates the accretion of the expanding phase with a binder matrix, consisting mainly of calcium hydrosilicates.

 In another embodiment of the invention, it is considered that said aromatic and fatty acids radically modify the texture and composition of the expanding phase — trisulfate in the volume of the cement stone. The function of aromatic acid consists in the formation of organomineral complex compounds of an intermediate nature, that is, existing for a short time, on the basis of an aluminum ion extracted by aromatic acid from the solid phase as a result of its acceleration of surface etching of the latter as compared to surface etching of sulfoaluminate components of NAO by water. From this point of view, aromatic acid can be called the etching component of the expanding additive. As a result, trisulfate forms highly dispersed polymolecular films around all particles of the specified hydraulic binder. This leads to the so-called cellular expansion mechanism, which is ensured by the growth of trisulfate crystals on a polymolecular film substrate around all solid cement particles in a cement-water suspension. From the topology it follows that for a given spatial arrangement (texture) of the expanding phase, the crystallization pressure of the trisulfate is used to the maximum in order to achieve shrinkage and / or expansion of the obtained products. The function of higher fatty acid is to protect these complex compounds of aluminum ions from the external environment (water vapor, hygroscopic moisture, carbon dioxide) with a hydrophobic film based on a double Stern layer until the moment when the mixing water penetrates the indicated polymolecular films. After this, the hydrophobic films from the surface of the particles are removed by a known mechanism [10] and go to the surface of cement products, namely cement stone, mortar and / or concrete, increasing their degree of water resistance.

In a further embodiment of the invention, these acids may not be present in their original market conditions, but in the form of solutions or melts. The physical meaning of this technical solution lies in the fact that, in fact, the indicated acids at the moment of performing the above functions are not actually in the initial, but in the specified modified states: when the binder is ground together or mixed with an expanding additive, homogenized substances are formed at the contact points of the particles aromatic acid dissolved in the hygroscopic moisture surrounding each particle binder and a spreading additive OH ^- -layer evaporating a point vysokotem eraturnyh zones of said contacts upon collision of particles and the grinding media during the grinding, where a temperature up to 550 ^o C (Bowden and Tabor, 1955), or when the contact friction at the points of entanglement particles during grinding and / or thorough mixing, where a temperature of up to 200 ^o C [11]. It is at these points that these aromatic complexes of aluminum ions arise, formed by chemisorption interaction with aluminum ions of the outer atomic layer of the surface of aluminum-containing components of NAO. At the same points, point zones of melts of higher fatty acids melt and correspondingly form, protecting the aromatic complexes of aluminum ions that arose at the indicated points from the external environment. Thus, in the finished cement product comprising the expanding additive according to the invention, these organic components of the expanding additive are presented in the indicated forms of solutions and / or melts, distributed in the form of films on the surface of the particles of the specified binder and expanding additive.

 The invention in terms of this additive becomes clearer from an example of its implementation, presented below.

Example 1. To obtain the additives according to the invention in the first series of experiments carried out in laboratory conditions, use:
raw materials:
additive components: accepted designations: sulfoaluminate clinker - SAK, calcined in a normal environment SAK1, in a reducing environment - SAK2; aromatic acid AK, including benzoic acid - AK1, sulfobenzoic acid, or benzenesulfonic acid - AK2; the highest fatty acid is high fatty acids, including stearic acid - high fatty acids, oleic - high fatty acids. Below is the mineralogical composition of Portland cement clinkers according to quantitative petrographic analysis; the mineralogical composition of the NAO - according to instrumental analysis methods: C ₁₂ A ₇ - according to infrared spectroscopy (the presence of an absorption band of IR spectra at a frequency of 0.640 m ^-1 , corresponding to Al ^VI - aluminum atom in the sixth coordination group), highly basic calcium sulfoaluminate - X-ray analysis according to the set of reflections according to Klein – Troxell [12], low-basic calcium sulfoaluminate, monocalcium aluminate, belite, anhydrite — according to the X-ray analysis according to the sets of ref lexes according to Taylor [13], impurities: alite (tricalcium silicate) according to the sets of reflexes according to Malinin [14]. The gross formulas of minerals of variable composition were determined by the method of selective chemical analysis in the modification of Panina et al. [fifteen].

,

C₂S 38, СА 10, С

13, примеси: С₁₂A₇ 5, C₃S 2, свободный оксид кальция 1, остальные, преимущественно соединения щелочных металлов в пересчете на Na₂O - 1;
САК2А:

,

, C₂S 33, СА 5, С

10, примеси: С₁₂A₇ 0,3, С₃S 0,5, свободный оксид кальция 0,5, остальные, преимущественно соединения щелочных металлов в пересчете на Na₂O - 0,7;
САК2Б:

,

, C₂S 12, СА 1, С

3, примеси: С₁₂A₇ 2, С₃S 0,5, свободный оксид кальция 0,2, остальные, преимущественно соединения щелочных металлов в пересчете на Na₂O - 1,3;
САК2В:

,

, C₂S 24, СА 2, С

6, примеси: С₁₂A₇ 1, С₃S 3, свободный оксид кальция 0,9, остальные, преимущественно соединения щелочных металлов в пересчете на Na₂O - 1,1;
АК1 - бензойная кислота техническая (валовая формула C₆H₅COOH), марки А, порошок белого цвета;
АК2 - сульфобензойная кислота техническая (валовая формула С₆Н₅SО₃Н), порошок белого цвета;
ВЖКС - кислота стеариновая техническая (валовая формула C₁₈H₃₆O₂), марки Т-3, хлопья белого цвета;
ВЖКО - кислота олеиновая техническая (валовая формула C₁₈H₃₄O₂), жидкость со слабым характерным запахом.The phase composition of sulfoaluminate clinkers (wt.%):
SAK1:

,

C ₂ S 38, CA 10, C

13, impurities: C ₁₂ A ₇ 5, C ₃ S 2, free calcium oxide 1, the rest, mainly alkali metal compounds in terms of Na ₂ O - 1;
SAK2A:

,

, C ₂ S 33, CA 5, C

10, impurities: C ₁₂ A ₇ 0.3, C ₃ S 0.5, free calcium oxide 0.5, the rest, mainly alkali metal compounds in terms of Na ₂ O - 0.7;
SAK2B:

,

, C ₂ S 12, CA 1, C

3, impurities: C ₁₂ A ₇ 2, C ₃ S 0.5, free calcium oxide 0.2, the rest, mainly alkali metal compounds in terms of Na ₂ O - 1.3;
SAK2V:

,

, C ₂ S 24, CA 2, C

6, impurities: C ₁₂ A ₇ 1, C ₃ S 3, free calcium oxide 0.9, the rest, mainly alkali metal compounds in terms of Na ₂ O - 1.1;
AK1 - technical benzoic acid (gross formula C ₆ H ₅ COOH), grade A, white powder;
AK2 - technical sulfobenzoic acid (gross formula C ₆ H ₅ SO ₃ N), white powder;
VZHKS - technical stearic acid (gross formula C ₁₈ H ₃₆ O ₂ ), grade T-3, white flakes;
VZhKO - technical oleic acid (gross formula C ₁₈ H ₃₄ O ₂ ), a liquid with a weak characteristic odor.

 The additive according to the invention is prepared by mixing the components in a laboratory stirrer LM1 of a cylindrical type with a length of 30 cm and a diameter of 5 cm, filled with steel balls with a diameter of 1.0-1.2 cm at 15 vol.% With the powder components of the additive and 30 vol.% With the mixture powdered and liquid components of the additive, for 20 minutes

The ingredients of these cement-water systems, namely: cement-water slurry and fine-grained concrete mixture, into which the additive according to the invention is introduced:
Portland cement PC1: from clinker of the following chemical and mineralogical composition (wt.%): chemical composition of the main oxides: SiO ₂ 21.80; Al ₂ O ₃ 5.29; Fe ₂ O ₃ 5.09; CaO 65.35; MgO 0.84; SO ₃ 0.38; R ₂ O 0.58; including K ₂ O 0.47 and Na ₂ O 0.27; the sum of 99.33, calculated characteristics: KN according to Kind 0.90; n 2.10; p 1.04; the content of the remaining small components: Li ₂ O≅0, BaO 0.07, SrO 0.002, NiO 0.031, CoO 0.02, Mn ₂ O ₃ 0.095, Cr ₂ O ₃ 0.188, MoO 0.054, TiO ₂ 0.02, P ₂ O ₅ 0.19, Cl ₂ 0, F ₂ 0; calculated mineralogical composition: C ₃ S 58, C ₂ S 19, C ₃ A 5.4, C ₄ AF 15.5, impurities - the rest. The content of two-water gypsum is 2.15 wt.%;
technical water for concrete and mortar according to GOST 23732-79.

In addition, the fine concrete for testing the additive according to the invention includes the following starting materials:
MZ - fine aggregate - sand quartz fraction 1-5 mm, containing, by weight. %: quartz 97, feldspars 2, dark-colored minerals - epidote and other impurities 1, with 38% voidness by volume;
KZ - coarse aggregate - crushed stone granite fractions of 5-10 mm, containing, by weight. %: granite 95, quartzite 3, mica and other impurities 2, with a voidness of 45% by volume.

 All raw materials meet the requirements of relevant standards and specifications.

 A cement-water suspension and a fine-grained concrete mixture with an additive according to the invention are prepared by combining the ingredients (the method of combination is described in example 3) in a laboratory forced-action mixer, cylindrical, with a vertical high-speed rotor equipped with a propeller mixer, a container for mixing and unloading the finished product according to GOST 30744-01. Mixing time - by stopwatch. Typically, the duration of mixing all the ingredients in the final stage, after the introduction of the additive according to the invention and the prototype and binder, was 5 minutes

 To test the additive according to the invention in the 1st series of experiments, it is introduced by preliminary mixing with cement into the tested cement material according to the options: α: cement paste (cement-water slurry) with W / C equal to wt. the ratio of water and cement in the cement paste of normal density, in this case 0.23; β: cement mortar mixture comprising Portland cement, water and fine aggregate in wt. ratio of 1: 0.5: 2; γ: cement fine-grained concrete mixture, including Portland cement, water, fine and coarse aggregates in wt. ratio of 1: 0.5: 0.6: 1.4.

 Thus, measurements of shrinkage and strength are carried out on samples from a hardening cement-water suspension or from a fine-grained concrete mixture with a W / C of 0.23 and 0.5, respectively.

In order to test the additive according to the invention in the 2nd series of experiments, it is introduced into cement by more thorough mixing, which is carried out in a laboratory two-chamber mill of periodic action lined with cast iron armored plates, with the dimensions of each chamber: length 0.28 m, diameter 0.5 m, rotation speed 48 min ^-1 , drive power 1.1 kW, engine speed 930 min ^-1 , grinding load on each chamber (with portland cement weighing approximately 10 kg in each chamber): tsilpebs ⌀ 20 mm • L 32 mm 5 kg mixing time is 15 minutes Next, the resulting mixture of Portland cement and additives in the given proportions is tested in the composition of three versions of cement-water suspension and fine-grained concrete, similar to those mentioned under the same names α, β and γ.

Cement-water suspension according to option α (cement paste) is prepared manually according to GOST 310.3-76; fine-grained concrete mixture according to options β and γ is prepared according to GOST 30744-01 using the propeller mixer described above. Standard materials-prisms (beams) with dimensions of 4 • 4 • 16 cm are made from prepared materials for physicomechanical testing of hardening cement-water slurry, fine-grained concrete without additives, with a known additive according to the prototype and with an additive according to the invention; Testing of samples is carried out according to the indicators: bending and compression strength according to the method of GOST 310.4-81. To measure linear strains of samples of these materials during hardening, namely, shrinkage / expansion strains, prepared samples are used to prepare prism samples with dimensions of 2 • 2 • 13 cm as follows. On a steel sheet, which is faced with the surface of the laboratory bench, collect molds for the manufacture of these samples, including each rectangular metal pallet, on which a steel frame is installed, including three slots for forming prisms. In the centers of the end walls (2 • 2 cm) of each nest there are hemispherical recesses that are filled with plasticine. In the latter, steel balls with a diameter of 5 or 6 mm are pressed into a depth of 2–3 mm, thereby fixing them on the walls of the nests in the frame. Then the frame is shaken several times, hitting the edge of the steel table lining to check the strength of the balls. After making sure that the balls hold tight, the prepared frames are mounted on steel pallets. The places of contact between the frames and pallets are carefully walled up with hot grease, consisting of a mixture of paraffin and rosin (3: 1), 4 g for each frame. Then the molds are filled with the indicated materials and compacted in the same way as they are done in the manufacture of samples for strength testing according to GOST 310.4-81, i.e. on a vibrating table with an oscillation frequency of 3000 min ^-1 , previously rigidly fixing the forms on the vibrating table using mechanical clamps.

48 ± 2 hours after mixing of the indicated materials, the prisms with balls installed in their ends are removed from the molds, marked and immediately placed in an air-moist environment with a relative humidity (W) of at least 95% and a temperature of 20 ± 3 ^o С (medium 1) . Next, the linear dimensions of the samples are measured after a specified time and compared with the first measurement made immediately after the formwork. For comparison, the linear deformation indices of samples hardened in air-dry conditions are measured in a similar way (W is maintained equal to 65 ± 5% at a temperature of 20 ± 3 ^o С - medium 2). The last measurement period of 2 months, as is known [16], is sufficient to obtain estimated linear strains of samples from hardening cement-water slurry (cement stone) and fine-grained concrete, provided that the previous measurement gave a result that differs from the final one by no more than 10%.

 To test the samples for compressive strength, a standard hydraulic press with a self-adjusting top plate is used, when bending (tensile when bending), a testing machine for loading the beams according to a three-point scheme, when testing shrinkage deformations, a device according to GOST 11052-74 for measuring linear shrinkage strains / extensions equipped with an hour indicator micrometer with a scale with divisions through 0.01 mm and two hands, of which the larger indicates fractions of a millimeter, and the smaller indicates millimeters, with each millimeter corresponding There is no full revolution of the big arrow. The indicator is equipped with a hemispherical recessed pin for tight contact with the balls fixed on the samples and fixed on the rails in such a way that the distance between the first indication of the indicator arrows and the lower end of the measuring cell into which the prism is mounted remains always constant and then changes as changes in the linear dimensions of prisms.

The compositions of the additives according to the invention, used in the experiments of example 1 and made by mixing the components, in mass ratios are as follows:
D1: SAK1 + AK1 + VZHKS = 1: 0,1: 0,1 (according to the prototype);
D2: SAK2A + AK1 + VZHKS = 1: 0,1: 0,1;
D3: SAK2B + AK 1 + VZHKS + VZHKO = 1: 0.1: (0.05 + 0.05);
D4: SAK2V + AK 1 + VZHKS + VZHKO = 1: 0,025: (0,1 + 0,1);
D5: SAK2V + AK 1 + VZHKS = 1: 0.3: 0.2;
D6: SAK2V + AK 1 + VZHKS + VZHKO = 1: 0.3: (0.01 + 0.01).

 The compositions of the additives according to the invention, made by means of pre-grinding SAC with other components, according to mass ratios are as follows: D7 - corresponds to D2, D8 - D3, D9 - D4, D10 - D5 and, finally, D11 corresponds to D6.

 The composition of the cement into which these additives are introduced is presented in table 1, lines 1-14.

The test results in both series of experiments are shown in table 1. Shrinkage data are given during storage of samples in medium 2, the compositions according to the invention are in lines 3 to 15, of which the compositions in lines 7, 8, 13 and 14 are optimums, in lines 3 -6 and 9-12 - the rest of the compositions. The data are compared with the test results of control cement without additives in row 1 of table 1 and with the composition of cement with an additive according to the prototype in row 2 of the same table. These data confirm the significant beneficial effect of the additive according to the invention, namely the presence of expansion or a significant reduction in shrinkage of products including the specified additive, while reducing its consumption to 1.5 - 4% of the mass of cement, that is, 1.7 to 4.7 times compared with the prototype, which leads to a decisive reduction in the cost of non-shrink Portland cement with the additive according to the invention and to the possibility of widespread use of such cement in various fields of construction and construction industry. In medium 1, the compositions of the cement-water systems with the additive according to the invention during the measurement period are expanding with expansion deformations of the cement stone to 0.3 mm / m after 28 days, which approximately corresponds to expanding Portland cement, comprising about 25% of the expanding additive [5] and at the current cost level, at least twice as expensive, and such a significant expansion is unattainable for cement with an additive according to the prototype. Note that there is a natural dependence of the properties of these materials with the additive according to the invention on its composition: the additive according to the prototype, comprising a significant amount (about 5% C ₁₂ A ₇ ), is much less effective; supplements containing increased amounts of both calcium sulfoaluminates — high and low basic — show best results. The presence of oleic acid in a mixture of higher fatty acids allows the use of lower temperatures of the mixture of mixing or domol of the additive according to the invention. The use of another aromatic acid instead of benzoic, in particular sulfobenzoic acid, allows one to obtain similar results, taking into account the properties of the latter, in particular, its rather sharp odor, therefore its content in the specified additive is reduced to the minimum within the specified limits. It should be noted that, like colmatizing additives according to GOST 24211-91 "Additives for concrete. General technical requirements", table 1, p. 19, according to the specified standard, increasing the waterproofing grade of cement products into 2 classes, expanding the additive according to the invention, as shown by experiments by its authors, it also increases the brand of these products for water resistance to the same extent, or more, depending on the composition of cement products.

 Thus, the first objective of the invention is the creation of additives for imparting non-shrink or expansion to hardening cement-water systems, at the same time significantly accelerating their hardening and acting at radically reduced concentrations in cement, namely within 1.5 - 4% of the mass of cement, achieved. From the prior art, such a result is considered even theoretically unattainable, which follows from the table of compositions of expanding cements given in the latest domestic review [17]. The above characteristics allow the use of the additive according to the invention as very effective, but to improve the quality and durability of the materials manufactured with this additive, in addition, it is necessary to select the optimal composition of non-shrink Portland cement and use the developed method for the manufacture of the specified cement according to the invention.

 Analyzing the state of the art in the field of non-shrinking and expanding waterproof cements, we note that of the currently known approximately 60 compositions of expanding and non-shrinking cements, all that have found wide practical application, except for one - gypsum-alumina expanding cement: a product of joint grinding of aluminous clinker or slag with gypsum stone in wt. a ratio of 7: 3 according to Budnikov and Kravchenko with an expansion after 28 days to 0.35% [5] are modifications of Portland cement, and for all, without exception, the expansion is based on the formation during hydration of higher amounts of trisulfate compared to Portland cement. When the heterogeneous trisulfate formation reaction ends as a result of the exhaustion of at least one of the ingredients that come into contact with each other in the liquid phase of the cement stone, the expansion of the latter ceases, and then it shrinks. At any moment of hardening, the fixed value of the volumetric or linear expansion of the cement-water system is the difference between the strains of the initial expansion and the continuous shrinkage. In expanding cements, the initial expansion exceeds the continuous shrinkage, in non-shrinkable cements, the initial expansion is approximately equal to shrinkage.

, или, при отклонениях от указанной формулы ввиду наличия примесей, - моносульфатом. Конверсия

происходит с выделением двух молекул сульфата кальция

и 12 молекул воды Н, обладающих повышенным потенциалом растворения и могущих активно воздействовать на имеющийся кристаллический сросток, то есть "скелет" цементного камня, растворяя основные контакты срастания и снижая прочность последнего. Указанной конверсии и сопровождающей ее быстрой усадки не происходит, когда в жидкой фазе цементного камня концентрация аниона

является равновесной трисульфату, причем показатель концентрации водородных ионов рН не ниже 11,5. Эти параметры вполне достижимы при твердении расширяющихся или безусадочных цементов с рационально подобранными составами и повышенным уровнем водонепроницаемости продуктов по сравнению с продуктами на основе портландцемента. Именно поэтому и существует промышленное производство указанных расширяющихся и безусадочных цементов.The shrinkage following expansion may be complicated by the phase transition of the trisulfate in the cement stone to a less flooded and less sulfur phase called calcium monosulfoaluminate

, or, in case of deviations from the specified formula due to the presence of impurities, monosulfate. Conversion

occurs with the release of two molecules of calcium sulfate

and 12 water molecules H, which have an increased dissolution potential and can actively affect the existing crystalline aggregate, that is, the "skeleton" of cement stone, dissolving the main contacts of the intergrowth and reducing the strength of the latter. The indicated conversion and the accompanying rapid shrinkage do not occur when the anion concentration in the liquid phase of the cement stone

is equilibrium with trisulfate, and the concentration of hydrogen ions, pH is not lower than 11.5. These parameters are quite achievable when hardening expanding or non-shrinking cements with rationally selected compositions and an increased level of water resistance of products compared to products based on Portland cement. That is why there is industrial production of these expanding and non-shrink cements.

и расширяющего ингредиента - сульфоалюминатного клинкера (САК), включающего (мас. %) сульфоалюминат кальция -

5 - 60, предпочтительнее 30 - 60, белит (C₂S) 20 - 50, ангидрит (

) 5 - 15, майенит (С₁₂A₇) 2 - 10 и свободную известь (С_cв) - остальное, взятых в мас. соотношении, соответствующем стехиометрии уравнения реакции образования трисульфата при гидратации расширяющегося цемента типа К:

При этом свободная известь в гидратной форме (СН) может присутствовать в составе САК и/или выделяться при гидролизе алита во время гидратации портландцементного (матричного) ингредиента расширяющегося цемента. Достоинство расширяющегося цемента типа К - повышенная сульфатостойкость при содержании С₃А в портландцементном клинкерном ингредиенте менее 6% и суммарном содержании SO₃ ≥ 6% массы цемента [9]. Другие расширяющиеся цементы на основе портландцемента по сульфатостойкости близки к портландцементу и незначительно превосходят его.The classification of industrially manufactured expanding or non-shrinkable cements used in the USA is known, based on the formation of an additional (compared to ordinary Portland cement) amount of trisulfate from additionally introduced into Portland cement in various mineral forms of alumina (Al ₂ O ₃ = A) or on an improved microstructure compared to conventional Portland cement trisulfate phases. In this case, there are three main types of similar cements [9]:
- Type K (by the name of the main author, Alexander Klein, USA, 1956, the first scientific publication in 1958 [12]), produced by joint or separate grinding, followed by mixing Portland cement clinker, gypsum

and an expanding ingredient - sulfoaluminate clinker (SAK), including (wt.%) calcium sulfoaluminate -

5-60, preferably 30-60, white (C ₂ S) 20-50, anhydrite (

) 5 - 15, mayenite (C ₁₂ A ₇ ) 2 - 10 and free lime (C _cv ) - the rest, taken in wt. the ratio corresponding to the stoichiometry of the reaction equation for the formation of trisulfate during hydration of expanding cement type K:

In this case, free lime in hydrated form (CH) can be present in the composition of NAO and / or released during the hydrolysis of alite during hydration of the Portland cement (matrix) ingredient of expanding cement. The advantage of type K expanding cement is increased sulfate resistance with a C ₃ A content in the Portland cement clinker ingredient of less than 6% and a total SO ₃ content _of ≥ 6% of the cement mass [9]. Other expanding Portland cement-based cements are close in terms of sulfate resistance to Portland cement and slightly exceed it.

, известь С_cв и γ-Al₂O₃, из их части возникает неустойчивый высокоосновный сульфоалюминат кальция (фаза Трокселла

), а при его разложении в ходе дальнейшего обжига -

с высвобождением извести, расходуемой на остальной глинозем с формированием С₁₂A₇. Кремнезем в САК связан в C₂S. Для ускорения минералообразования вводят минерализаторы, например, фториды, что превращает С₁₂A₇ во фтормайенит С₁₁А₇Сf или - при восстановительной среде - в сульфидное производное майенита

. Возможен обжиг белитового портландцементного клинкера из сырьевой смеси с добавками боксита и гипса, в котором одновременно с

формируется алит (С₃S) на основе взаимодействия с белитом извести, выделяющейся из разлагающегося высокоосновного сульфоалюмината кальция - упомянутой фазы Трокселла [12], причем такой сульфоалюминатный клинкер (неравновесного состава, так как C₃S и

термодинамически несовместимы) с добавкой 6% гипса позволяет получить высокопрочный расширяющийся портландцемент марки 550 - 600 с контролируемым расширением [18].NAO is produced by calcining, before sintering, the raw mix of limestone, bauxite and gypsum, usually by the dry method in order to avoid thickening of the sludge, and anhydrite C • is initially formed during heating of the mixture

, lime С _St. and γ-Al ₂ O ₃ , from their part arises an unstable highly basic calcium sulfoaluminate (Troxell phase

), and when decomposed during further firing -

with the release of lime spent on the rest of the alumina with the formation of C ₁₂ A ₇ . Silica in the NAO is bound in C ₂ S. To accelerate mineral formation, mineralizers, for example, fluorides, are introduced, which turns C ₁₂ A ₇ into C ₁₁ A ₇ Cf fluoromeenite or, in a reducing medium, into a sulfide derivative of mayenite

. It is possible to roast Belite Portland cement clinker from a raw mix with the addition of bauxite and gypsum, in which simultaneously

alite (С ₃ S) is formed on the basis of interaction with lime belite released from the decomposing highly basic calcium sulfoaluminate - the mentioned Troxell phase [12], and such a sulfoaluminate clinker (of non-equilibrium composition, since C ₃ S and

thermodynamically incompatible) with the addition of 6% gypsum makes it possible to obtain high-strength expanding Portland cement of 550–600 grade with controlled expansion [18].

- Type M (by the name of the main author - Viktor Vasilievich Mikhailov, USSR, the idea in unpublished reports - 1935, the first publication - 1941, the first copyright certificate of the USSR - 1947 [19]) - a product of joint grinding or separate grinding with the subsequent mixing of the Portland cement ingredient, namely Portland cement clinker, or Portland cement, alumina cement (in Russia at present - alumina slag, in the aforementioned work [17] - prepared from the latter in a digester calcium hydroaluminates) and gypsum ingred cient to exemplary wt. ratio 70: (10 - 15): (15 - 20). In the first version of the composition with calcium hydroaluminates, called waterproof expanding cement (WRC), it was produced in Moscow by Metrostroy (1947 - 1976) to caulk instead of lead waterproof seams between elements of cast-iron or reinforced concrete lining of subway tunnels (tubing). In another version of the composition with alumina cement and asbestos additives without additional gypsum (only with the gypsum that is contained in Portland cement) under the name quick-hardening sealing composition (BUS - Y.N. Novikov et al., USSR, 1975), it continues to be produced in Moscow Metrostroy (since 1976) for the same purpose. In a further embodiment with a high content of alumina cement and gypsum, it is a tensile cement, as discussed below. The ARC sets in a few minutes and develops the initial strength with an initial W / D of 0.25 - 0.3 due to monosulfate and without the formation of trisulfate, which was always emphasized by its main author - V.V. Mikhailov. The formation of monosulfate as the first hydrate phase is associated with large-scale crystallization in the digester of the initial SAN ₁₀ and C ₃ AN ₆ in an expanding agent and medium-high alkaline Portland cement used as a matrix ingredient, including alkali metal compounds Na and K in terms of Na impurities in terms of Na ₂ O in an amount of 0.8-1.1% by weight of the clinker component of the specified Portland cement ingredient. Only upon contact of the material of the coiled VRC seams between the tubing with cold water coming from the surrounding soil, trisulfate is formed in the hardening cement test from the VRC with an increase in the volume of the solid phase and, expanding, closes the capillary pores. BEAD simultaneously forms mono- and trisulfate, but the pore locking mechanism is similar to that described. The expanding portland cement belongs to the same type of expanding cements (ROC, IV Kravchenko, Yu.F. Salomatina-Kuznetsova et al., USSR, 1954 [5]) - a product of co-grinding of ingredients (wt.%): Alite Portland cement clinker, comprising more than 7% C ₃ A, 60 - 65, alumina slag 5-7, two-water gypsum 7 - 10 and active mineral additives 20-25. The Russian Orthodox Church was produced of grade 400 (class 32.5) with a total non-shrinkage or expansion of 0.03 - 0.1% at three cement plants in Russia for three years (since 1965) as cement that quickly hardened when steaming concrete (isothermal heating - total 3-4 hours versus 8-12 hours on ordinary Portland cement), but due to the presence of an expensive alumina ingredient, the difficulty of controlling the composition of the four-component batch mixture and the lack of constancy of properties (unacceptably high dispersion of strength indicators), its production was discontinued in 1968).

- Type S (by the name of Hans Schwiete [N. E. Schwiete], West Germany, who discovered together with U before Ludwig in 1954 the phenomenon that Portland cement with a high content of C ₃ A is more than 8% and two-water gypsum - more than 6% by weight with relatively coarse grinding is almost non-shrinking due to the formation of an increased amount and an improvement in the microstructure of trisulfate.20 More precise crystallization and an increase in the average length of trisulfate fibers increase the average size of drusen trisulfate crystals and, accordingly, the value of the generalization pressure exerted by the mentioned drusen on the moving elements of the matrix of hardening cement stone, which leads to an increase in the expansion of the latter. active mineral additives - ash or slag with a high content of soluble alumina (Schwite, Ludwig et al. , 1956 - see the review [21]), raw or calcined prior to dehydroxylation of alunite ore (mentioned above), etc. These cements (including those with the addition of calcined alunite) grade 400 (class 32.5) with a total expansion to 0 , 03–0.3% were produced periodically by 1–2 cement plants in Germany and the USSR, but in Russia during the years of perestroika their industrial production ceased and partially restored on a new raw material base - high-aluminate shales discovered in North Ossetia [22].

Crystallization components (“krents”) obtained from kaolin treated with sulfuric acid or “red gypsum” - ferrous sulfate mixed with sulfuric acid - a waste product from the production of pigment titanium dioxide from ilmenite (also used as an expanding agent for non-shrinkable cement of type S) are also used. CaTiO ₃ ) by the sulfuric acid method. They contain alumina and sulfate anions and are suitable for the production of expanding type S cement. This cement contains, by weight. h.: Portland cement clinker 80–90, krent 10–20 and, if necessary, the addition of gypsum 5–10 [23] and it is used for waterproofing subway tunnels instead of bus in Ukraine.

Of the other expanding agents, in addition to trisulfate, freshly calcined calcium and magnesium oxides are also known, but expanding cements based on them are used for non-building purposes. So, on the basis of freshly burnt lime, an non-explosive destructive substance (NRV) was created. It differs from building lime in that it is burned during rapid heating and at a particularly high temperature (1250 - 1550 ^o С) in order to ensure the small sizes of CaO crystals in the finished NRV - 10 - 15 microns. To use NRV, a destructible structure is drilled, laid in the drilled boreholes of the NRV in a dry state, water is added at a low final mass. the ratio of water to cement (W / C) is about 0.15 - 0.2, and after 1 day the surrounding concrete is destroyed when the distance between the holes is 0.7-1 m (Onoda-Semento company, Japan - since 1985, I .G. Luginina, USSR, since 1989, see review [17]).

 On the mechanisms of expansion of cements, including expanding agents, there is no single point of view. They can be classified as follows: expansion occurs under the influence of: 1) crystallization pressure of the expanding agent; the first to indicate this reason in cit. A. Lossier's work on trisulfate; this is also confirmed by the practice of the manufacture and use of non-explosive destructive substances; an experimental estimate of the local crystallization pressure of 3–7 MPa (V.I. Khaimov-Malkov, USSR, 1966) indicates the effect of a cumulative (cumulative) mechanism; without the accumulation of pressure, its magnitude is not enough for expansion; 2) the osmotic pressure developed on the membranes (shells) of hydration products around cement particles, under which there is a layer of the internal liquid phase with a high concentration of dissolution products, and around these membranes (shells) there is an external liquid phase with a reduced concentration of dissolution products; therefore, water from outside penetrates into the membranes (shells), which leads to the expansion of cement stone (this expansion mechanism was first discovered on the basis of the analysis of experimental data by S. Chatterjee and J.W. Jeffrey, England, 1966; it was predicted by A.E. Sheikin and T.Yu. Yakub in the USSR in 1961); experimental assessment of the magnitude of this pressure, performed by I.N. Akhverdov with sotr. in the USSR in 1961 - 4-5 MPa - also requires taking into account the cumulative effect during expansion; 3) the conversion of monosulfate -> trisulfate "in the solid phase" (VV Mikhailov, USSR, 1947 - cited copyright certificate [19]); according to all these mechanisms, an increase in W / C should lead to a decrease in the magnitude of expansion; this is what is happening. According to this indicator, it is still difficult to choose between these mechanisms. A comprehensive expansion mechanism based on the theory of swelling of double electric layers by means of osmotic absorption of water by the charged surface of a growing crystal, which replaces, in the authors' opinion, crystallization pressure, was considered in [17].

 Due to the large number of operating factors, the general theory of the mechanism of expansion of cements does not exist. T.V. Kuznetsova (USSR, 1986 [24]), as the necessary conditions for the expansion of the first one, switched to a geometric or, more precisely, a stereological approach to this theory: she notes the simultaneous appearance of: 1) a structural basis common to the entire volume of material, that is, a semi-rigid matrix hardening cement stone; 2) an expanding phase connected to this matrix in an experimentally selected amount. Until both of these conditions are satisfied, expansion is impossible, since the plastic deformations of the coagulation base, without partial crystallization of the matrix, are quenched. After partial crystallization of the matrix, expansion begins and continues until the expansion energy is greater than the energy of the mechanical reaction of the matrix under tension under the action of the expanding agent. The presence of the matrix provides the mentioned cumulative effect. Moreover, the expansion stress for expanding cements of the indicated types is, according to various estimates, ranging from 0.3 - 0.8 MPa for type S RCs, 1.5 to 2 MPa for type M RCs and 2.5 to 3.5 MPa - for type K RCs, and the tensile strength of a cement stone (matrix) at bending by 12-24 h of hardening is approximately at the same level. This explains the expansion at the level of 0.3 - 0.8%, followed by shrinkage after 3-6 months to the resulting expansion, respectively 0.1 - 0.4%.

 As for the so-called tensile cement, through its use V.V. Mikhailov supposed to avoid cracking in the stretched zone of reinforced concrete elements, for example, floor slabs in buildings, for which it is necessary to compensate tensile stresses by compressing (prestressing) the cement stone under the influence of tensile cement from external load. For full compensation, prestressing is necessary at the level of tensile strength of concrete equal to (for the main classes of concrete in strength) from 1/7 to 1/10 of compressive strength, that is, from 1.5 to 6 MPa. However, in fact, the level of cracking is about 0.65 - 0.7 of the breaking load, so compensation is only 0.3 - 0.35 of the ultimate tensile strength of concrete, which allows you to calculate the required level of prestressing equal to: 0.35 (1.5 - 6) = (0.53 - 2.1) MPa. Such and a higher level of prestressing was indeed obtained in concrete based on type M RCs developed by V.V. Mikhailov et al. [19] under the name: stress cements (SC). These cements are a joint grinding product (wt.%) Of the following ingredients: Portland cement clinker (or Portland cement) 65–67, monoaluminate alumina slag (or alumina cement) 18-22, gypsum (two-water) 13-15. The final expansion of this composition in cement stone reaches 2.5%. From a comparison with the composition of the WRC, it is seen that in order to increase the degree of expansion and the energy of self-stress by 1.5-2 times, it was necessary to increase the content of the expanding agent - the alumina-containing ingredient of the SC - by only 3 - 5 wt.% Due to the reduction in the volume of the Portland cement matrix. A further increase in the content of the alumina-containing ingredient, although it increases the energy of self-stress, is not so noticeable, and when it contains 30% of the cement mass or more, the strength of the cement as a whole begins to decrease. The extreme nature of this dependence can be explained on the basis of the stereological approach. Stereology is a relatively new (formally existing since 1957 - after the First International Congress on Stereology in Berlin) section of mathematics that studies the spatial distributions of figures and bodies and their properties. Used in the study of the structures of materials.

 We reformulate the above conditions for the expansion of cement by T.V. Kuznetsova in the stereological sense as follows. The first condition - the formation of the base of the structure - is the formation of a multiply connected matrix, the elements of which fill the volume of the cement stone in such a way that any arbitrarily drawn line (generally a volume curve) will have a non-zero probability of meeting any two and / or three matrix elements . By "connectivity" is meant the ability to draw at least one line through any randomly selected neighboring matrix elements, and this line is also included in the matrix by all points. Two and / or three matrix elements are selected because the one-dimensional matrix doubly connected in each element — the “snake” - is freely deformable, the three-dimensional matrix of rods in each element — the “diamond structure” and its derivatives — is completely non-deformable, whereas two -c-half-connected on average, that is, a mixture of a two-dimensional matrix (with flexible biconnected one-dimensional elements) and a three-dimensional matrix (with multiply connected three-dimensional regions) characterizes the sought intermediate, boundedly deformed state (and bending volume / surface). The second condition - the presence at the beginning of expansion of the required amount of expanding agent - is equivalent to the presence of such a volume of expanding agent, which simultaneously has an expanding effect on the entire volume of the matrix. Otherwise, uneven changes in the volume of the matrix will appear, which, as you know, causes cracking.

We first consider the first of these expansion conditions. According to the stereological theorem of A. Gerland (USA, 1958 [25], see in Russian its other conclusion according to V. S. Markin [26], or a statement of Gerland's conclusion according to KS Chernyavsky [27]), in a two-phase matrix of arbitrary thickness, a continuously extended simply connected phase of arbitrary configuration passes through the entire volume of the matrix in one dimension (through the thickness of the matrix, which is equivalent to the breakdown of the matrix by a filtered liquid in terms of penetration theory) with a probability different from zero, provided that it occupies a fraction equal to not less than 20% of the total ma Ritsa. From this theorem it follows, firstly, that for independent meetings of this simply connected phase with each of two, including adjacent point elements of the matrix, the Gerland theorem is fulfilled when this phase is filled with at least 0.2 + 0.2 = 0.4 of the matrix volume . Thus, Corollary 1 of Gerland's theorem is as follows: the condition for the cumulation of expansion stresses in the matrix is that at least 40% of the matrix volume is filled with the expansion phase. By analogy, to meet with three adjacent matrix elements, generally not lying on the same plane, Corollary 2 of Gerland's theorem can be formulated as follows: the condition for the formation of a rigid matrix structure that stops expansion is that the matrix is filled with at least 60% of the system volume. By system volume here is meant the sum of the initial volumes of cement and water in a cement-based material. When W / C = 0.5, the sum of the specific volumes of cement and water, referred to the initial volume of cement, is (0.5 • 3.15 + 1): 1 = 2.58 (here 3.15 is the ratio of the density of cement and water ; the decrease in the sum of the specific volumes of the initial solid phases of cement and water compared with the specific volume of hydrates, called contraction - on average about 10% by volume - is not taken into account). The volume of the initial cement here is 1: 2.58 = 0.39, i.e. approximately 40% of the volume of cement stone. The expanding phase should fill at least 40% of 60% of the remaining volume, i.e. 24% of the volume of cement stone. For this, the volume of hydrates should be 24: 40 = 0.6 of the volume of the initial cement, and the mass minimum degree of hydration G _{min of} cement, corresponding to this, taking into account the average density of hydrates of 2.67 g / cm ³ and their average porosity of 30%, is calculated from ratios:
(3.15: 2.67) • 1.3G _min = 0.6; G _min = 0.6: (3.15: 2.67): 1.3 = 0.39 ≅ 40%.

и

. Если учесть, что пористость многоводных гидратов в 1,5 раза больше средней пористости маловодных гидратов, равной примерно 30%, то есть составляет 45%, а средняя плотность трисульфата 1,775 г/см³, кажущиеся удельные объемы много- и маловодных гидратов относятся как [(1 : 1,775) • 1,45] : [(1 : 2,67) • 1,3] = 1,667; следовательно, 20 об.% расширяющейся фазы в составе новообразований соответствует 20 : 1,667 = 12% по массе. Считая массовое отношение

в портландцементе в среднем равным около [1+3•1]: 10, то есть 0,4, при степени реакции

около 0,7, значениях степеней гидратации через 3 суток С₃А 40% и С₃S 30% и, пренебрегая контракцией, получаем, что содержание расширяющей фазы (трисульфата и его аналогов, обозначаемых кратко AFt-фазы) в новообразованиях обычного портландцемента к концу первых трех дней твердения составляет примерно: {[1 • 0,4 + 3 • 1] • 0,7} : [10 • 0,3] = 0,79 по объему. Это дало основание О.П. Мчедлов - Петросяну (СССР [Украина], 1967 г.) справедливо утверждать, что начальная прочность портландцемента (в возрасте до 3 суток) определяется трисульфатной (эттрингитной) матрицей, для расширения которой имеется свободный объем пор, что и не позволяет расширению проявиться (А.Е. Шейкин, 1967 г.).So, the level of hydration of the Portland cement ingredient, equal to 40%, corresponds to the construction of a flexible matrix without the formation of high-water hydrates -

and

. If we consider that the porosity of high-water hydrates is 1.5 times higher than the average porosity of low-water hydrates, which is approximately 30%, that is, 45%, and the average density of trisulfate is 1.775 g / cm ³ , the apparent specific volumes of high- and low-water hydrates are related as [ (1: 1.775) • 1.45]: [(1: 2.67) • 1.3] = 1.667; therefore, 20 vol.% of the expanding phase in the composition of neoplasms corresponds to 20: 1.667 = 12% by mass. Considering the mass ratio

in Portland cement an average of about [1 + 3 • 1]: 10, that is, 0.4, with the degree of reaction

about 0.7, the values of the degrees of hydration after 3 days C ₃ A 40% and C ₃ S 30% and, neglecting contraction, we find that the content of the expanding phase (trisulfate and its analogues, denoted by AFt-phase) in neoplasms of ordinary Portland cement the end of the first three days of hardening is approximately: {[1 • 0.4 + 3 • 1] • 0.7}: [10 • 0.3] = 0.79 by volume. This gave rise to O.P. Mchedlov - Petrosyan (USSR [Ukraine], 1967) it is fair to say that the initial strength of Portland cement (up to 3 days old) is determined by the trisulfate (ettringite) matrix, for the expansion of which there is a free pore volume, which does not allow the expansion to appear (A .E. Sheikin, 1967).

 When taking into account hydrated hydrates, the minimum degree of cement hydration to create a flexible matrix is actually substantially less - namely 40%: 1 [(0.79 • 1.45): (0.21 • 1.3)] = 9.5% . Here, 1.45 and 1.3 are the values of the coefficients of the increase in porosity, expressed in fractions of a unit, for the phases of multi- and low-water hydrates, respectively. It is known that the degree of hydration of the Portland cement ingredient of a portion of RC close to 10% is achieved somewhat later than the setting time, usually by the end of the first 12 hours of hardening. This is the deadline for fulfilling these stereological conditions. That is why the expansion of cement begins about 12 hours after mixing with water. With finer grinding of cement, an increased amount of expanding agent is required to start expansion, since an increased degree of hydration of the Portland cement (clinker) cement ingredient when finely grinding the latter reduces the average water content in hydrated shells and compacts them, which leads to a decrease in the values of the mentioned coefficients and, accordingly, to delayed onset and reduced final magnitude of expansion.

 A similar calculation based on the aforementioned Corollary 2 of Gerland's theorem for the formation of a rigid matrix shows that a rigid structure should fill at least 60% of 60% of the remaining volume, i.e. 36% of the total volume. For this, the volume of hydrates should be 36: 40 = 0.9 of the volume of the original cement. The required degree of hydration (G) of the latter, without taking into account the increase in the number of high-water hydrates that have already formed, is: G = 0.9: (3.15: 2.67): 1.3 = 59%, i.e. approximately 60% as much as possible possible mass of hydrated neoplasms. The increase in G compared with the necessary for the formation of a flexible matrix should be at least 20% only due to external (i.e. located outside the original cement particles) low-hydrates, the amount of which should reach: 9.5 + 20 = 29.5, or approximately thirty%. However, in calculating the degree of hydration, one must also take into account the inevitable formation of internal (within the previous boundaries of cement particles) hydrates, which do not directly participate in the formation of the matrix. When W / C = 0.5, the ratio of external and internal hydrates by weight is approximately 1: 0.6. Therefore, the required degree of hydration should be higher than the calculated value by (1 + 0.6): 1 = 1.6 times, that is, 30 • 1.6 = 48%, or about 50% (calculation accuracy - not more than 10% ) In hardening Portland cement with a W / C of about 0.5, this degree of hydration of the clinker part is achieved on average in two weeks. Considering in addition that in the composition of RCs, Portland cement clinker hydrates faster than in Portland cement due to the binding of hydrolytic lime in high-water hydrates, and the content of the latter is approximately two times higher than in Portland cement (which reduces the required degree of hydration for the formation of a rigid matrix from 50 to 40%), it should be concluded that the rigid matrix of the SC is created after about 7-14 days of hardening. That is why its expansion is usually stabilized by this time.

 Consider the second expansion condition by T.V. Kuznetsova [24] is a condition of self-tension proper. Taking into account the volume of particles of the initial cement included in the matrix, the volume fraction of the solid part is: (1 + 0.9): 2.58 = 0.736 = about 74% of the total volume, which corresponds to 26% of capillary porosity. If the expanding agent is considered the Gerland phase “breaking through the entire structure”, then the self-tension corresponds to the condition for the formation of the expanding phase in the amount of (0.2 + 0.2 + 0.2) • 74 = 44.4 vol.% ≅ 45 vol.% Solid parts, or 45 • 0.74 = 33% of the total volume. Hence, Corollary 3 of Gerland’s theorem: in the same approximation, the minimum content of expanding agent necessary for self-stress in cement is 33: 1.667 = 19.7% ≅ 20% by weight. This theoretical result really corresponds to the compositions of SC used in practice.

 Thus, two criteria for self-stressing of cements have been theoretically established (two necessary and sufficient conditions): 1) the proportion of external main hydrates in the total volume of the cement-water system is at least 30 vol.% (If the matrix is created only by Portland cement ingredient, then the minimum required degree of hydration its clinker part - 50 wt.%, in the composition of the SC - about 40 wt.%); 2) the content of the expanding (straining) agent is not less than 20 wt. % At the same time, it was taken into account that part of the expanding agent is involved in the creation of a common structure matrix. The stereological approach allows us to similarly calculate the composition of RC and SC with other expanding agents, as well as other expanding and annoying binders.

Currently, the cement industry periodically produces tensile cements with an expansion energy (self-stress) of 10, 20, 40 kgf / cm ² , subdivided into types NTs-10, NTs-20 and NTs-40 (according to TU 21-20-43-80 " Expanding self-stressing cement "- the first type, according to TU 21-20-18-80" Stressing cement "- other types) in accordance with the content of the expanding agent, evaluated, in particular, by the ratio of Al ₂ O ₃ / SO ₃ in the finished SC equal to 2.3 - 2.4 for the SC - 10, 1.8 - 2.1 for the SC-20 and 1.4 - 1.8 for the SC-40. Experimental batches of NTs-60 were also produced. However, taking into account the real need for SCs of only the first two types, since this is sufficient for not opening cracks in the stretched zone of reinforced concrete structures (see above), as well as the difficulty in producing two other types of SCs and the relative instability of their characteristics during storage, they are usually limited by the use of SCs -10 and NC-20. Color Scientific Center in Kazakhstan Sas - Tyubinsky cement plant under the direction of G.I. Chistyakova was made in the following composition (wt.%): White or bleached Portland cement clinker 65-75, SAK 10-15 and gypsum stone 3.7-5 (in terms of SO ₃ ). Cement met the technical requirements according to TU 21-20-40-80 and in terms of color characteristics met the requirements of GOST 15825-80 "Portland cement colored. TU". The non-colored NTs is used for the manufacture of waterproof concrete and reinforced concrete layers and elements in the construction of subways in a number of cities of the CIS countries, in particular, in Moscow, Minsk, St. Petersburg, Novosibirsk, for concreting roll-free (concrete) roofs of residential buildings in Moscow, Almaty and other cities, for the construction and waterproofing of swimming pools in Russia, Belarus, Kazakhstan, Ukraine, as well as in the USA, including swimming pools and tanning salons on flat ceilings of tall buildings in Chicago and Detroit (USA), for hydro isolation and waterproofing of sports arenas of a number of stadiums in many CIS countries and in the USA The total output of SCs of all kinds around the world over the past two decades, however, is small - only about 200 thousand tons, of which 3/4 in our country. This, given the limited raw materials for the required number of expanding agents, is not yet enough to interest large architectural firms and world-class architecture masters in this material.

 The above indicates that the content of the expanding agent known in the prior art as a part of expanding and non-shrinking cements, prevailing at present in industrially expanding and non-shrinking cements and theoretically justified, averages 20 wt.% For stress and 14 to 16 wt. % for non-shrinking cements. Since the average cost of expanding agents is currently about 4-5 times higher than the average cost of Portland cement, expanding cements are more expensive than Portland cement on average in [(4 ... 5) • 0.2 + 1 • 0.8]: 1 = 1 , 6 ... 1.8 times, and non-shrinking cements - on average in [(4 ... 5) • (0.14 ... 0.16) +1 • (0.86 ... 0.84 )]: 1 = 1.42 ... 1.6 times. This significantly limits their use and, in any case, excludes their use as general-purpose cements. In addition, the production of these valuable cements per unit mass of the expanding agent is only 1: 0.2 = 5 mass units for stress cement and 1: (0.14 ... 0.16) = 7.1 ... 6, 25 units of mass for non-shrink cement. Given that in Russia, alumina slag, the main material for the expanding agent, is produced from bauxite in blast furnaces that were put into operation back in 1939 and are currently fully amortized, and in many European countries there are no bauxite deposits of their own, the source material for the development of expanding agents have to be imported from abroad, the consumption of an expanding agent as part of an expanding and non-shrinkable cement is of critical importance, especially since both practically and theoretically from the prior art and the existing theory does not see the possibility of reducing the consumption of the expanding agent. This is a major disadvantage of expanding and non-shrink cements known in the art.

, или моноалюминат кальция СА, или майенит С₁₂А₇ или смесь указанных минералов с мольным отношением С/А менее 3, а также сульфат кальция в форме ангидрита С

или гипса С•SH₂ в массовом соотношении с сульфоалюминатом или алюминатом кальция примерно 1 : 2, и органический - любой жидкий гидрофобизатор и, кроме того, дополнительно включающий доменный гранулированный шлак в качестве демпферного ингредиента, регулирующего расширение [31], при следующем соотношении указанных компонентов, мас.%:
Расширяющая добавка: минеральный компонент - 9 - 60
Расширяющая добавка: органический компонент - 0,1- 1,5
Доменный гранулированный шлак - 20 - 88
Матричный ингредиент - портландцементный клинкер или портландцемент - Остальное
Главным недостатком указанного вяжущего является высокий расход расширяющегося агента, хотя в минимуме (9,1 мас.%) он соответствует допустимому.Known non-shrink Portland cement, including ground Portland cement clinker, or Portland cement, as well as an expanding agent and an organic additive [28], characterized in that it contains alumina cement as an expanding agent, and as an organic additive, is a shrinkable Portland cement. cellulose ethers, specifically methyl cellulose or carboxymethyl cellulose, in the following ratio of components (wt.%):
Expanding Agent - 13 - 19
Organic Ingredient - 0.01 - 1
Matrix ingredient - Portland cement clinker or Portland cement - Else
Closest to the proposed invention in terms of the composition of the hydraulic binder (prototype) is a hydraulic binder, including Portland cement and / or its varieties and / or a product of joint or separate followed by mixing of grinding Portland cement clinker and gypsum stone, as well as an expanding additive containing components: mineral : calcium sulfoaluminate

or calcium monoaluminate CA, or C ₁₂ A ₇ mayenite or a mixture of these minerals with a C / A molar ratio of less than 3, as well as calcium sulfate in the form of anhydrite C

or gypsum С • SH ₂ in a mass ratio with calcium sulfoaluminate or calcium aluminate is about 1: 2, and organic - any liquid water-repellent agent and, in addition, additionally including blast furnace granulated slag as a damping ingredient that regulates expansion [31], in the following ratio of these components, wt.%:
Expanding additive: mineral component - 9 - 60
Expanding additive: organic component - 0.1-1.5
Granulated blast furnace slag - 20 - 88
Matrix ingredient - Portland cement clinker or Portland cement - Else
The main disadvantage of this binder is the high consumption of expanding agent, although at a minimum (9.1 wt.%) It corresponds to the permissible.

 The objective of the present invention in terms of the composition of the binder is a radical reduction in the content of the expanding additive in the specified binder, allowing for the expansion, or at least the shrinkage of the latter. Such a reduction allows a decisive increase in the volume of introduction of the specified binder in the construction complex.

This problem is solved in that in a hydraulic binder, which is a product of joint or separate, followed by mixing the grinding of the matrix ingredient and expanding additives, including Portland cement and / or its varieties - products of joint and / or separate followed by mixing as a matrix ingredient providing strength grinding Portland cement clinker and gypsum stone, and as an expanding additive - a mixture containing components: mineral - sulfoaluminate clinker and organic - fatty acid, the organic component contains a higher and additional aromatic acid, and the sulfoaluminate clinker has a composition, wt.%:
Low basic calcium sulfoaluminate - 20 - 65
Highly basic calcium sulfoaluminate - 15 - 3.0
Dicalcium silicate - 0.5 - 55
Monocalcium Aluminate - 1 - 5
Anhydrite - 3 - 10
Impurities - Rest
at wt. the ratio in the composition of the specified additives specified mineral component and each of these acids in the organic component 1: 0.025 - 0.3: 0.02 - 0.2, respectively, with the following wt. the ratio in the specified binder of Portland cement clinker, gypsum stone in terms of sulfur trioxide and the specified expanding additives 100: 2-4: 1,5-4.

 The essence of the invention in terms of the composition of the specified cement is that the expanding additive included in it includes organic components, which, in contrast to the prototype available in cement, carry out: aromatic acid - etching of aluminate components of the additive and Portland cement clinker, leading to their accelerated release parts in the adsorption layer; Higher fatty acid - protection of organoaluminate complexes released into the adsorption layer from atmospheric agents - moisture and carbon dioxide. Since the aluminate components of these additives and Portland cement clinker are characterized by non-stoichiometric compositions and, accordingly, nonequilibrium crystal lattices, this etching leads to a sharp acceleration of their interaction with water after mixing of the last finished cement, as well as to a corresponding decrease in the size of the nuclei and crystals of the expanding phase and their distribution throughout the surface of the binder along the absorption layer of organic matter almost from the very beginning of the hardening process. The stereological conditions of Gerland expansion mentioned above in this case are satisfied under the only condition that the entire surface of the binder is occupied by the thinnest net layer of the expanding phase. In this case, no line passing through the volume of the cement stone can pass this phase. The converse statement is also true: no point of the indicated volume can avoid participation in the deformations caused by the expanding phase distributed in this way. With this new cell-like stereological scheme of the arrangement of the expanding phase in the cement according to the invention, the consumption of the expanding additive required by experiment to achieve the stability of the latter is 1.5-4% by weight of the binder. This is several times lower than that provided for according to the prototype and determines the fundamental novelty of both the composition of the specified cement and its expansion mechanism. The specified composition provides coverage of the expanding phase in the form of a cellular system of all sections of the cement matrix formed in the hardening cement stone. All newly emerging hydrates, including expanding high-water ones, grow inside adjoining shells from the indicated hydrophobized wire mesh, “thrown” during joint grinding or separate grinding, followed by mixing all particles of the matrix cement ingredient and then expanding along with the increase in gel volume of high-water hydrates and its crystallization. Coalescence of hydrates and the formation of a coherent matrix of cement stone occurs in this case through the cells of the aforementioned mesh. The combination of these processes is the reason for the initial expansion and subsequent shrinkage of the cement according to the invention at the indicated extremely low consumption of expanding agent, unexpected in comparison with the prior art.

With a lower content of the sum of both calcium sulfoaluminates in the sulfoaluminate clinker than 35 parts per 100 parts of the expanding additive, the consumption of the expanding agent in the composition of the specified cement increases above the specified ratio, which reduces the economic part of the effect of the invention due to the increase in the cost of cement. When the total amount of calcium sulfoaluminates in the sulfoaluminate clinker is more than 95 wt. hours per 100 wt. including the expanding additive, difficulties arise in firing the specified clinker, which worsens its microstructure and reduces its activity, and at the same time leads to an increase in the required consumption of the specified additive and reduces the technical and economic effect of the invention. An additional amount of gypsum compared to that present in the matrix ingredient - Portland cement - is introduced into the expanding agent when the content of gypsum С • SH ₂ in the composition of Portland cement and С • S anhydrite in the sulfoaluminate clinker is insufficient to complete the formation of trisulfate by stoichiometry of the sulfoaluminate reaction calcium with gypsum and water after mixing the last cement according to the invention, while monosulfate appears in the cement stone instead of trisulfate.

 The essence of the invention in terms of the composition of cement becomes clearer from an example of its implementation.

 Example 2. Conditions and materials for carrying out the invention - as in example 1.

 The compositions of the specified binder under various conditions of combining it with the additive vary in accordance with the data given in table 2.

 The test results of the obtained binders (cements) indicate: 1) the hydraulic binder according to the invention can indeed be manufactured at such low expansions of the expanding agent (1.5-4%), not known either from the prior art or from the modern level of the theory of expansion of cements (for example , according to the review [17]). Moreover, the cost of non-shrink waterproof cement according to the invention for the first time only slightly exceeds the cost of control Portland cement, and from a unit mass of expanding additive in this case, it is possible to produce from 25 to 67 mass units of non-shrink waterproof cement according to the invention, which will increase the achievable production and use of cement according to the invention at least five times as much as achievable with the prior art; 2) the results presented in Example 1 are confirmed and testify to the increased efficiency of combining the expanding additive with other cement ingredients by means of domol (series of experiments 2) as compared to mixing (series of experiments 1), since the strength and deformation properties of cements are in lines 8-12 table 2 is higher than similar in composition of cements in rows 3-7 of this table; 3) with an increase in the content of the specified additive in the cement composition with a simultaneous decrease in the content of gypsum stone with both methods of introducing the specified additive into the cement according to the invention (lines 3-7 and 8-12 of this table), the strength and deformation properties of cement pass through extrema, with maximum strengths (lines 5 and 10) do not match the expansion maxima (lines 6 and 11); the latter account for large values of the gypsum stone content and smaller ones for the content of the specified additive in cement compared to the maximum strengths; An explanation of this result requires further research; 4) while increasing the content of the specified additive and gypsum stone in the cement composition (lines 10, 13 and 14 of the table), the strength and deformation properties of cement are also characterized by extreme dependence, namely, they pass through the maximum strength and expansion - but with the same composition cement - on line 13 of table 12. This can be explained by the fact that with an excess of gypsum stone in the cement stone for up to 7 days, free gypsum remains, fixed by the method of L.A. Gudovich, an admixture of which loosens the structure of the hydrosilicate matrix of cement, which somewhat reduces the strength characteristics and contributes to the shrinkage of cement stone, which reduces expansion, despite the increase in the number of expanding additives. Therefore, in this case, a further increase in the content of the latter in the cement composition is impractical, whereas when the additive content is less than 1.5% of the mass of the cement clinker ingredient, its properties, as shown by experiments, quickly approach the cement according to the prototype, significantly reducing some of the beneficial effects of the invention. In general, the advantages of the cement according to the invention in comparison with the control cement that does not contain additives (row 1 of table 2), and with cement according to the prototype (row 2 of this table) according to the above data are obvious.

It should be noted that the temperature of the mixture of ingredients, equal to 60 ^o C and above, in the specified process of grinding / mixing the components of the specified additives is usually easily achievable, since freshly burnt Portland cement clinker coming out of the furnace refrigerator and representing the most common matrix ingredient has a temperature of about 60 - 100 ^o С, and together with other cement ingredients, it is additionally heated during grinding of the latter by about 30 - 60 ^o С. Thus, the melting condition of these organic of the constituents of the expanding additive by co-grinding or mixing said ingredients is generally practicable in practice without additional energy costs.

 The foregoing allows us to conclude: the above results indicate that the second goal of the invention is the creation of a non-shrinking or expanding hydraulic binder, close in composition and cost to Portland cement - achieved.

 The indicated advantages of this technical solution are manifested most clearly only in the manufacture of cement according to the invention in the most efficient way.

A known method of manufacturing a non-shrink waterproof Portland cement, including as a matrix ingredient providing strength, Portland cement clinker, or Portland cement, as well as an expanding additive, by joint grinding or milling of these ingredients, characterized in that said cement contains a mixture of calcium sulfate as an expansion additive, calcium oxide and aluminate component, namely alumina cement or calcium hydroaluminate, taken in the following ratio (wt.%) [ 29]:
Portland cement clinker or Portland cement - 58-62
Expanding Additive - 38-42
and joint grinding of the components is carried out to a dispersion level corresponding to the absence of final shrinkage of the obtained cement after hardening for up to 1 year.

 The advantage of this technical solution is that the cement obtained by this method is quite homogeneous and its composition is easily controlled by the content of free calcium oxide in the mixture. The main disadvantage, in addition to the high cost of the product due to the enormous consumption of the expanding agent, is the hygroscopicity of the cement obtained. As a result of hydration with moisture from the air during storage, the latter loses its properties within about one week. Therefore, it is impossible to create a sufficient supply of this cement except in an airtight container, it is not possible to store it in silos and ship in bulk, and even in an airtight container it crumbles as a result of partial hydration of the matrix ingredient with gypsum moisture and hygroscopic moisture of the starting components. Therefore, this cement can be produced only directly at the place of use, which, as a rule, is inconvenient and significantly limits the possibilities of applying this technical solution.

 There is also known a method of manufacturing a similar cement by additional introduction into the specified composition with the joint grinding of the components of an organic additive, namely a water repellent (asidol - soap) [30]. However, according to the data cited by M.I. Khigerovich in the scientific and technical report of the Research Institute of Cement (Moscow, 1957), the hygroscopicity of this cement by the addition of asidol - soaponaf was not eliminated.

, или моноалюминат кальция СА, или майенит С₁₂А₇ или смесь указанных минералов с мольным отношением С/А менее 3, а также сульфат кальция в форме ангидрита С •

или гипса С•SH₂ в массовом соотношении с сульфоалюминатом или алюминатом кальция примерно 1 : 2, и органический - любой жидкий гидрофобизатор и, кроме того, дополнительно включающий доменный гранулированный шлак в качестве демпферного ингредиента, регулирующего расширение [31], при следующем соотношении указанных компонентов (мас.%):
Расширяющая добавка: минеральный компонент - 9 - 60
Расширяющая добавка: органический компонент - 0,1- 1,5
Доменный гранулированный шлак - 20 - 88
Матричный ингредиент - портландцементный клинкер или портландцемент - Остальное
а смесь указанных компонентов совместно измельчают до удельной поверхности, обеспечивающей сохранность полученного цемента в течение стандартного гарантийного срока.Closest to the proposed invention in terms of a method of manufacturing a hydraulic binder (prototype) is a method of manufacturing a hydraulic binder, comprising, as a matrix ingredient, providing strength, Portland cement and / or its varieties and / or a joint or separate product with subsequent mixing of the grinding of Portland cement clinker and gypsum stone, as well as an expanding additive containing components: mineral: calcium sulfoaluminate

or calcium monoaluminate CA, or C ₁₂ A ₇ mayenite or a mixture of these minerals with a C / A molar ratio of less than 3, as well as calcium sulfate in the form of anhydrite C •

or gypsum С • SH ₂ in a mass ratio with calcium sulfoaluminate or calcium aluminate is about 1: 2, and organic - any liquid water-repellent agent and, in addition, additionally including blast furnace granulated slag as a damping ingredient that regulates expansion [31], in the following ratio of these components (wt.%):
Expanding additive: mineral component - 9 - 60
Expanding additive: organic component - 0.1-1.5
Granulated blast furnace slag - 20 - 88
Matrix ingredient - Portland cement clinker or Portland cement - Else
and a mixture of these components is jointly crushed to a specific surface that ensures the safety of the resulting cement during the standard warranty period.

 The advantage of this method is reduced in comparison with the prior art for industrially manufactured expanding and non-shrinking cements, the minimum content of the expanding agent is 9 wt.% And the degree of surface protection of the latter with a water repellent increases due to the adsorption inertness of the slag component prevailing in quantity and, accordingly, in the total specific surface in relation to water repellent. Inertness of the slag helps to increase the concentration of water repellent on the surface of the expanding agent and, accordingly, to increase the safety of the cement obtained compared to those described above, but storage for two months, that is, the standard warranty period, as shown by the experiments of the authors of the present invention, for cement obtained by the method according to the prototype remains impossible due to lumpiness. The main disadvantage of this technical solution remains the hygroscopicity of the cement obtained, although less pronounced compared to that of products obtained by the methods according to [29, 30]. In addition, the presence of blast furnace granulated slag in this case causes an increase in energy consumption for grinding the specified cement in comparison with the previous technical solutions and the prior art.

 The objective of the present invention in terms of the method of manufacturing the specified cement is to ensure uniform distribution in the resulting cement of the expanding additive in the form of a solution in its own organic components on the surface of all the solid particles of the specified cement, which can significantly increase the preservation of the cement according to the invention, namely at least to level of safety of ordinary Portland cement.

This problem is solved by a method of manufacturing a hydraulic binder by joint or separate, followed by mixing the grinding matrix ingredient and expanding additives, including as a matrix ingredient providing strength, Portland cement and / or its varieties, obtained as a product of joint and / or separate with subsequent mixing of Portland cement grinding clinker and gypsum stone, and as an expanding additive - a mixture containing components: mineral - sulfoaluminate clinker and organic - fatty acid, characterized in that they take fatty acid - the highest and optionally aromatic acid, and sulfoaluminate clinker having a composition, wt.%:
Low basic calcium sulfoaluminate - 20 - 65
Highly basic calcium sulfoaluminate - 15 - 30
Dicalcium silicate - 0.5-55
Monocalcium Aluminate - 1 - 5
Anhydrite - 3 - 10
Impurities - Rest
at wt. the ratio in the composition of the specified additives specified mineral component and each of these acids in the organic component 1: 0.025 - 0.3: 0.02 - 0.2, respectively, and the following wt. the ratio in the specified binder of Portland cement clinker, gypsum stone in terms of sulfur trioxide and the specified expanding additive 100: 2 - 4: 1,5 - 4, and firing before sintering the specified sulfoaluminate clinker is carried out in a reducing medium under temperature conditions, ensuring the content of impurities in the composition , wt.%: tricalcium silicate (3CaO • SiO ₂ ) 0.5 - 3 and mayenite (12CaO • 7Al ₂ O _s ) and / or its halide and / or sulfide derivatives 0.3 - 2, and joint or separate followed by by mixing grinding the specified matrix ing units with an expanding additive are conducted until an expanding phase is formed on the particles of the resulting binder of a uniformly distributed hydrophobized film of the expanding phase, which is established by the criterion for the formation of a globular mass homogenized by mixing the latter with grinding after mixing the binder with water until a homogeneous water-binder suspension is obtained.

 In an embodiment of the method, the amount of said globular mass is 40-100% of the volume of the water-binder suspension.

 The essence of the invention in terms of expanding additives is that the composition of the NAO according to the invention, obtained by firing before sintering in a reducing medium, is absent. The essence of the invention in terms of a method of manufacturing a hydraulic binder at the stage of manufacturing a sulfoaluminate clinker as a component of an expanding additive is to regulate the phase composition of the specified clinker by selecting a sintering temperature during firing in a reducing atmosphere. With this design composition of the sulfoaluminate clinker with a saturation coefficient providing for the formation of a highly basic calcium sulfoaluminate, it is he who first forms; if free lime remains at the moment the calculated amounts of both calcium sulfoaluminates are complete, then an alite admixture begins to form from belite and, at the same time, a highly basic sulfoaluminate begins to decompose with the formation of a mayenite impurity. The task of the technologist is to stop the sintering process exactly at the moment when the content of both of these impurities remains in the specified minimum limits. This corresponds to the maximum efficiency of the specified sulfoaluminate clinker in the composition of the specified additives and, accordingly, the minimum consumption of the specified additives in the composition of the hydraulic binder. Otherwise, the content of mayenite rises to a level approaching the sulfoaluminate clinker in the additive according to the prototype mentioned above in the description of the invention, which ultimately requires an increase in the consumption of expanding additives in the composition of the finished cement. When the indicated impurities appear, the reducing atmosphere promotes the inclusion of additional anions in their composition, which reduce their harmful effect on the effectiveness of the expanding additive. So, sulfate ion is introduced into the composition of mayenite, under the given conditions in the form of sulfide. The sulfide derivative of mayenite is less active than the original mineral and does not have a significant adverse effect on the effectiveness of the expanding additive.

It should be noted that in practice there is no time to determine the content in the firing product of the alite impurity by the X-ray diffraction method or by infrared spectroscopy — the mayenite impurity that forms simultaneously. The latter means that a sufficient criterion for the content of both impurities within the indicated limits is the appearance of mayenite in the sulfoaluminate clinker in limited quantities by the characteristic feature of the formation in the aqueous suspension of powdered sulfoaluminate clinker in micropreparations studied under an optical microscope directly during firing, in particular, directly on the firing furnace head, characteristic gel-like spherical formations around some clinker particles, including an admixture of mayenite (1-2 spheres in the floor f vision of an optical microscope with an increase of about 200 and at a concentration of the specified clinker in an aqueous suspension of about 1% of the mass of water for the above upper acceptable concentration limit of C ₁₂ A ₇ in the specified clinker or the appearance of the first sector of such a sphere in similar preparations corresponding to the lower acceptable the concentration limit of C ₁₂ A ₇ in the specified clinker). These spheres consist of the hydrogel Al (OH) ₃ or AlO (OH) with an external birefringent shell of crystals of calcium hydroaluminates. For the first time, these spheres were identified by O.M. as a sign of mayenitis. Astraeva [32], the first using synthetic mayenite to show that these gel and crystals are characteristic hydrate formations during its interaction with water.

The essence of the present invention in terms of a method of manufacturing a hydraulic binder at the stage of cement production is that when melting a higher fatty acid during grinding or mixing a matrix ingredient with an expanding additive, their dissolving ability increases due to demicellization of molecules unattainable at room temperature, and the corresponding growth of opaque abilities of the unit mass of the organic components of the additive in the form of an adsorption layer covering all particles of the finished cement . In this case, the mineral component of the expanding additive is in an encapsulated state, that is, as part of organic hydrophobized capsules. This allows, firstly, to extend the shelf life of the cement obtained according to the invention to a level corresponding to the standard shelf life of ordinary Portland cement, that is, up to two months, and secondly, to exhibit a new hydrophobization effect, due not only to organic, but to mineral-organic the adsorption layer surrounding each particle of cement made according to the invention. This effect consists in the formation immediately after mixing with water of a globular mass, that is, not a dough, but a mass of water-binders (cement-water) globules that turn into a familiar cement dough only by grinding with a trowel. This criterion allows you to select both the consumption of expanding additives in the composition of cement, and the fineness of grinding of the latter. Experiments show that with a minimum allowable specific surface area of cement of approximately 250 m ² / kg, an increase in grinding fineness to a level of approximately 400 m ² / kg requires an increase in the consumption of this additive to fill the entire surface of said adsorption network. With an increase in the specific surface area of cement in excess of about 400 m ² / kg, the need for a further increase in the consumption of expanding additives disappears, since the increase in strength and elastic modulus of the matrix compensates for a further decrease in the consumption of expanding additives per unit surface area of the finished cement.

The expression of the adequacy of the consumption of expanding additives and the specific surface of the finished cement is the aforementioned effect of globular hydrophobization, previously unknown from the prior art. The most economical option is to achieve this effect with a minimum consumption of additives and a minimum specific surface area of cement obtained according to the invention. In practice, the consumption of the additive is set by means of a weight batcher at the minimum limit (1.5% of the mass of cement) and the specific surface area of the product is controlled within the range of 250 - 400 m ² / kg, achieving the described hydrophobization effect. If it is absent in the specified range of dispersion of the cement, the consumption of the expanding additive is increased to 2 or 2.5% of the mass of cement and the operation of searching for the indicated effect is repeated while controlling the specific surface. In the manufacture of the cement according to the invention by mixing the matrix ingredient of Portland cement and the expanding additive, the achievement of the indicated effect of globular hydrophobization is also achieved by controlling two factors: the consumption of expanding additive and the duration (in this mixer), or the mixing efficiency (in various mixers; the latter factor refers to the specific energy intensity of the worker volume of each mixer). The higher the duration or effectiveness of mixing, the lower the consumption of expanding additives with constant dispersion of cement. This is how the data obtained above and given in tables 1 and 2 are obtained.

 It should be noted that without firing sulfoaluminate clinker according to the criterion of a limited content of alite and mayenite impurities, it is impossible to achieve the indicated degree of globular hydrophobization of the finished cement, since mayenite is not hydrophobic.

 The hydraulic binder made by the method according to the invention does not crumple and can be stored in silos and shipped in bulk or in containers along with Portland cement. Considering the cost, only slightly exceeding that for Portland cement, and the possibility of long-term storage without loss of technical properties, the hydraulic binder according to the invention with this manufacturing method can be used as cement for general construction purposes, which fundamentally improves the implementation possibilities of the present invention compared to all previously known expanding and non-shrinking cements.

 The invention in terms of a method of manufacturing a hydraulic binder becomes clearer from an example of its implementation.

Example 3. Conditions and materials for the implementation of the invention, as in example 1. The manufacturing parameters and test results of manufactured cements are presented in table 3. The feature of these tests is that they determined the preservation of cements, that is, their strength and shrinkage deformation in concrete samples laid in storage immediately after the manufacture of cements, as well as in samples laid 60, 90 and 180 days after storage of cements in the laboratory at a temperature of 20 ± 3 ^o C and a relative humidity of 65 ± 5%. The magnitude of the decrease in strength and the growth of shrinkage deformations or the reduction of expansion deformations of these samples of equal age after different storage periods judge the ability of cements to be stored for a long time.

The results obtained allow us to conclude the following: 1) control cement, which does not contain an expanding additive, is characterized by well-known growth rates of strength, shrinkage, loss of strength and increase in shrinkage during storage (row 1 of table 3), typical of Portland cement and is representative from this point of view; 2) in this case, an increase or decrease in the specific surface area of the control cement compared to the indicated optimum (330 m ² / kg) leads to an increase in shrinkage or a decrease in strength compared with the indicated characteristics, as well as to a deterioration in the preservation of cement in terms of strength or shrinkage, respectively; 3) low-shrink cement according to the prototype (row 2 of table 3) is characterized by increased strength, especially at an early age, compared to the control cement, but an increased aging rate during storage according to the shrinkage rate, even compared to the control cement. This usually applies to aging in terms of strength of expanding cements known from the prior art, but low-shrink cement, made according to the prototype, in aging does not age faster than control Portland cement, which is its advantage. Nevertheless, an increased aging rate compared to Portland cement is generally characteristic of expanding and non-shrinking cements known from the prior art, which is ignored in the extensive patent and scientific literature on these cements. This justifies the skepticism of R. Bogga, who was considered the largest scientist in the field of chemistry and technology of cement in the 20th century, with respect to these cements, expressed in his most famous work [33] in the following wording: “It should be noted that the enthusiasm of lawyers for various slag and special cements It is not supported by many manufacturers and researchers of cement. It is felt that some of the advantages and achievements of these cements are not fully proven, and as for expanding cements, there are difficulties in defining and controlling ie the degree of expansion may jeopardize their application the idea "; in fact, to a large extent, due to this uncertainty, all expanding cements, which found industrial application in the second half of the 20th century, that is, after the publication of the cited work, contain an excess of expanding agent against the requirements of the stereological theory (in excess of 20 wt.%) so that aging less affected the magnitude of the expansion; 4) cements according to the invention (lines 3-5 of table 3), including expanding additives based on sulfoaluminate clinkers calcined in a reducing atmosphere at an optimum temperature in the sintering zone of the furnace (shown in column 4 of table 3), despite a record low content of expanding additives ( 2 - 3.5%), practically do not age in terms of strength and linear deformations, and only cement, including D2 additive based on sulfoaluminate clinker SAK2A (composition in example 1), ages, although slightly, in terms of shrinkage; this is the second major surprise of the invention, if the first is to consider the achievement of stability when the content of expanding additives in the composition of cement is only 1.5 - 4% by weight. At the same time, cement in row 4 of table 3, including additive D3, despite the high specific surface area (460 m ² / kg), practically does not age either in terms of strength or in terms of linear deformations up to six months of storage, which corresponds to the effect of globular hydrophobization corresponding to 100% by volume of globules in cement paste. Note that when using additives D7 - D9, obtained not by mixing, but by combining the components, the test results similar to those shown in table 3 are even better. This also applies to the determination of water tightness in concrete samples, in terms of which the aging of cements is approximately similar to aging in strength indicators, and is practically absent in cements made by the method according to the invention. It should be noted that data on aging of expanding cements in terms of water resistance are not available in well-known literature, which is explained by only an even higher rate of aging of known expanding cements in terms of water resistance compared to decreasing strength indicators.

 The data obtained indicate that non-shrink waterproof cement made by the method according to the invention can indeed be hydrophobized with the mineral component of the expanding additive calcined according to the method according to the invention and the grinding parameters of the ingredients also according to the method according to the invention. The specified cement is able to be stored for a long time without loss of technical properties, which was not previously known for non-shrinking and especially expanding cements and is unexpected in comparison with the prior art, especially taking into account the unusually low content of the expanding additive.

 The specified features of the expanding additive, a hydraulic binder with its use and the method of manufacturing the specified binder according to the invention, including the absence of difficulties in controlling the production of these additives, cement and cement products, contribute to the widespread industrial implementation of this invention.

 Thus, the present invention is fully prepared for industrial implementation.

Claims (7)

1. An expanding additive based on sulfoaluminate clinker for the manufacture of non-shrinking or expanding products when it is introduced into a hydraulic binder, including a matrix ingredient, namely Portland cement and / or its varieties, including components: mineral - sulfoaluminate clinker and organic - fatty acid, characterized in that the organic component contains fatty acid - higher and additionally - aromatic acid, and sulfoaluminate clinker has a composition, wt. %:
Low basic calcium sulfoaluminate - 20-65
Highly basic calcium sulfoaluminate - 15-30
Dicalcium silicate - 0.5-55
Monocalcium Aluminate - 1-5
Anhydrite - 3-10
Impurities - Rest
when the mass ratio in the composition of the specified additives specified mineral component and each of these acids in the organic component 1: 0,025-0,3: 0,02-0,2, respectively. 2. The expanding additive according to claim 1, characterized in that as a low basic calcium sulfoaluminate it includes a mineral with a gross formula 4CaO • 3Al ₂ O ₃ • SO ₃ , and as a high basic calcium sulfoaluminate a mineral with a gross formula (7-9) CaO • (2-3) Al ₂ O ₃ • 2SO ₃ , as a dicalcium silicate - a mineral with a gross formula (1.8 - 2.3) CaO • SiO ₂ , as a monocalcium aluminate - a mineral with a gross formula CaO • Al ₂ O ₃ and as anhydrite - a mineral with a gross formula CaSO ₄ .  3. The expanding additive according to claim 1 or 2, characterized in that it contains benzoic acid as aromatic acid and stearic acid or oleic acid or a mixture of the latter in a weight ratio of 1: 5 to 5 as the highest fatty acid : 1 respectively.  4. The expanding additive according to any one of paragraphs. 1-3, characterized in that it contains these acids in the form of their solutions and / or melts. 5. A hydraulic binder, which is a product of joint or separate grinding, followed by mixing the matrix ingredient and expanding additives, including Portland cement and / or its varieties as products of the matrix ingredient, which provide joint and / or separate grinding and subsequent mixing of Portland cement clinker and gypsum stone, and as an expanding additive - a mixture containing components: mineral - sulfoaluminate clinker and organic - fatty acid, characterized in that the organic component contains a higher and additional aromatic acid fatty acid, and the sulfoaluminate clinker has a composition, wt. %:
Low basic calcium sulfoaluminate - 20-65
Highly basic calcium sulfoaluminate - 15-30
Dicalcium silicate - 0.5-55
Monocalcium Aluminate - 1-5
Anhydrite - 3-10
Impurities - Rest
when the mass ratio in the composition of the specified additives of the indicated mineral component and each of the indicated acids in the organic component is 1: 0.025-0.3: 0.02-0.2, respectively, with the following mass ratio in the specified binder of Portland cement clinker, gypsum stone in terms of sulfur trioxide and said expanding additive 100: 2-4: 1.5-4. 6. A method of manufacturing a hydraulic binder by joint or separate, followed by mixing the grinding of the matrix ingredient and expanding additives, including as a matrix ingredient providing strength, Portland cement and / or its varieties - products of joint and / or separate, followed by mixing the grinding of Portland cement clinker and gypsum stone, and as an expanding additive - a mixture containing components: mineral - sulfoaluminate clinker and organic - fatty acid, distinguishing that they take fatty acid - higher and additionally - aromatic acid, and sulfoaluminate clinker - having the composition, wt. %:
Low basic calcium sulfoaluminate - 20-65
Highly basic calcium sulfoaluminate - 15-30
Dicalcium silicate - 0.5-55
Monocalcium Aluminate - 1-5
Anhydrite - 3-10
Impurities - Rest
when the mass ratio in the composition of the specified additives of the indicated mineral component and each of the indicated acids in the organic component is 1: 0.025-0.3: 0.02-0.2, respectively, and the following mass ratio in the specified binder of Portland cement clinker, gypsum stone in terms of sulfur trioxide and the specified expanding additive 100: 2-4: 1.5-4, moreover, firing before sintering the specified sulfoaluminate clinker is carried out in a reducing medium under temperature conditions, ensuring the content of impurities in the composition, wt. %: Tricalcium silicate (3CaO • SiO ₂₎ and 0.5-3 mayenita (12SaO • 7Al ₂ O _s) and / or a halogenide and / or sulfide derivatives of 0.3-2, and jointly or separately, followed by mixing of said milling a matrix ingredient with an expanding additive is carried out until the particles of the resulting binder get a uniformly distributed hydrophobized film of the expanding phase, which is established by the criterion for the formation of a globular mass homogenized by mixing the binder with water after mixing eat until a homogeneous water-binder suspension.  7. The method according to p. 6, characterized in that the amount of said globular mass is 40-100% of the volume of the water-binder suspension.

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