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    • 专利摘要:
    Procedure to prepare a cementitious composite, mortars and micro-nanostructured concretes with a long life in service, comprising said composite. The present invention relates to a process for the preparation of a cementitious composite comprising: 1) a first stage of conditioning of silica nanoparticles, in which they are heated to a temperature between 85-235º c, for a sufficient time interval to achieve a maximum moisture percentage of 0.3% with respect to the total weight of the material resulting from this first stage, 2) a dry dispersion stage in which the particles conditioned according to step 1) are dispersed on cement and in which inert grinding balls are used, 3) a stage of conditioning of the cementice composite obtained in stage 2), in which the used grinding balls are separated from the obtained cementice composite, To the composite obtained, to cement derivatives comprising this composite, preferably mortars and concretes, to its method of preparation and to the use of these materials in the industry. (Machine-translation by Google Translate, not legally binding)
    公开号:ES2610511A1
    申请号:ES201531373
    申请日:2015-09-25
    公开日:2017-04-27
    发明作者:José Francisco Fernández Lozano；María Pilar LERET MOLTO；Amparo MORAGUES TERRADES；Encarnación REYES POZO；Jaime Carlos GÁLVEZ RUIZ；Elvira SÁNCHEZ ESPINOSA；Daniel ALONSO DOMÍNGUEZ；Inmaculada ÁLVAREZ SERRANO
    申请人:Consejo Superior de Investigaciones Cientificas CSIC；Universidad Politecnica de Madrid；Universidad Complutense de Madrid；
    IPC主号:
    专利说明:

     PROCEDURE FOR PREPARING A MICRO-NANOESTRUCTURED COMPOSITE CEMENTICEO, MORTARS AND CONCRETE LONGER IN SERVICE, THAT UNDERSTAND THIS COMPOSITE The present invention is in the field of cement-decomposing technology and 5 cement-derived materials, such as mortars and concretes, and their preparation procedures Use in industry, especially in the construction sector. STATE OF THE TECHNIQUE Cements are the basis of the materials used in construction such as mortars and concrete. Cement is the most commonly used material in civil construction; said material is mainly composed of silicate phases, aluminate phases, gypsum and, to a lesser extent, ferrite. When hydrated, these components give rise to crystalline phases and other amorphous phases, known as hydrated calcium silicates (C-S-H gels). C-S-H gels account for more than half of the total hydrated products and are primarily responsible for the mechanical properties of cement-based materials. These gels consist of finite chains of tetrahedra [SiO4] that share vertices, which are repeated following the pattern (3n-1), where n is an integer that accounts for the possible absence of tetrahedra arranged in the bridge position in the structure. The incorporation of additional materials to improve the characteristics of these materials obtained from cement is a field of great interest since it is in this way to improve their critical characteristics and expand and improve their applications. nanoparticles in cement-based building materials such as mortars and concretes have been shown as an interesting procedure for their improvement of resistant capacities and / or for the contribution of functional properties. In this way, 25 different classes of existing nanoparticles are incorporated to increase mechanical properties or achieve new benefits such as: hydrophobicity, photocatalysis, electromagnetic shielding, bactericidal or fungicidal character, etc. In this sense it is described that the addition of graphene nanoparticles in The form of nanoplates produces a restriction on the penetration of CO2 (WO2015084438 A1). The main limitation in the preparation of materials is the high requirement of organic additives for processing since they present workability problems. (WO2015084438 A1 and KR20150036928 A). A strong limitation in the use of nanomaterials for cementitious materials is that it implies greater complexity in its execution by requiring specialized personnel and personal protective equipment that are not common in the construction sector.35 The incorporation of aluminum, alumina, dioxide nanoparticles of titanium, indium-tin oxide, tinned tin oxide with particular aluminum, or zinc oxide with a size below the visible, less than 150nm, in the coating mortar layer in a concrete provides reflective properties in the range infrared (DE102012105226 A1). The limitations of the method are related to the incorporation of polyurethane in the coating and the subsequent spraying of 40nanoparticles by projection or infiltration that make a complex and expensive process in commissioning. Other processes for incorporating nanoparticles consist of the use of aqueous suspensions with silane coupling agents to achieve hydrophobic effects once they are applied to mortars or concrete (CN103275616 A). The use of hardening processes by means of autoclave or semi-autoclave treatments that improve resistance to acids if nanoparticles of silica aerosols are used in water-oil emulsions with sodium carbonate in mortars that cover metal parts is described in UA56379 U. On the other hand, the durability of the coatings incorporating nanoparticles applied on mortars or concrete is not contemplated since it is limited by the surface location of the nanoparticles itself.50The addition of 1-3% by weight of nanosilica to a PORTLAND SAUDI TYPE-G cement allows its use in oil wells at high temperatures (290ºF equivalent to 143ºC) and high pressure (ca. 55-62 MPas) (US2014332217 A1 ). The preparation method requires the use of high shear up to 12000 rpm to disperse the nanosilica particles. In a process of incorporation of up to 20% of inorganic nanotubes based on silicoaluminates, aqueous dispersions are required prior to their incorporation into the cementitious compositions (AU2013323327 A1). Other processes involve the use of dispersants in aqueous solutions to pre-disperse the nanoparticles (CN103664028 A) (RU2474544 C1). The improvement in properties however is partly limited by the difficulty in the dispersion processes of the nanoparticles. The addition of bohemite nanoparticles between 2 nm and 80 nm 10 together with silicon oxide, calcium oxide and magnesium oxide by a percentage of up to 25% to increase the compressive strengths of mortars up to <73 MPas with only 0.75% by weight of alumina nanoparticles (US2014224156 A1). The application WO2010010220 refers to the dry dispersion of nanoparticles on microparticles, however, it does not suggest the need to carry out a previous stage of conditioning before dispersion, since in the examples described in WO2010010220 a prior conditioning is not carried out. Structural properties up to values of cement type 72.5-82.5 requires mechanical-chemical activation processes of Portland cement through grinding until reaching specific surface values of 300-900 m2 / kg and the incorporation of polymer additives 20 (WO2014148944 A1). These methods require a high energy consumption and cause an increase in the volume of the material that is also difficult to store and handle due to its high reactivity. The incorporation of glycerin favors the nucleation of crystals based on calcium silicate with a reduction of its size for an improvement of its mechanical resistance and allows the use of high pressures for compaction in oil well applications (EP2695850 A1). However, a limitation of the state of the art is that the presence of a larger volume of crystals makes the material weaker, in particular when hydration changes occur as occurs with the phases of etringite that evolve during the setting to calcium monosulfoaluminate and whose subsequent hydration causes accelerated degradation of the material.The mortar waterproofing is achieved with silica nanoparticles up to 10% by weight and 30-25% by weight of additives using mixing processes with speeds of 1440 rpm and times of 45 minutes ( CN102718446 A). The nanoparticles allow the reduction of permeability by assuming that they are located in the interstices of the cement and aggregate particles (CN102378743 A) and preferably favor the formation of the Etringite phase during setting (DE102012105226 A1). The appearance of etringite may be limiting for the durability of the mortars 35 if their transformation occurs at phases with volume change. The limitations of these processes however are claimed for particles between 0.1 to 1 mm. In the state of the art, the location of nanoparticles in cementitious mixtures and to a lesser extent in final composites due to the complexity of mortars and concrete is not unequivocally demonstrated. In the state of the art, the processes for incorporating nanoparticles into cementitious compositions are not standardized and are insufficient to achieve the mechanical resistance and waterproofing properties required for long-lasting products, in particular larger-sized para-aggregates, as in the case of concrete. For decades, numerous researchers have employed different types of additions in Portland cement, seeking to modify the porosity, morphology, composition and structure of CSH gels, in order to improve the durable and resistant properties of starting cement. In the last two decades, cement-based materials have been prepared and studied with additions of nano and microsilica, obtaining great improvements over ordinary Portland cement. These improvements have been related to aspects concerning the composition and structural aspects of the C-S-H gels, for whose study the techniques of Silicon nuclear magnetic resonance 29, 29 Si-MAS-NMR, and scanning electron microscopy, SEM, are of great interest. Piper et al. studied cement pastes with nanosilica additions and found, through 29Si-MAS-NMR, thatthese led to higher degrees of hydration and longer chain lengths of silica gel from the CSH gel than the ordinary Portland cement paste they used as a reference (Piper, JJ, Campillo, I., Guerrero, A., “Reduction of the calcium leaching rate of cement paste addition of silica nanoparticles ”Cem. Concr. Res, 2008: 38, pp. 1112-1118). Two years later, Mondal et al. They also verified this fact when comparing samples with additions of micro-and nanosylic. They also observed that the samples with nanosilica substantially improved the durable properties of ordinary Portland cement (Mondal, P., Shah, SP, Marks, LD, Piper, JJ, “Comparative study of the effects of microsilica and nanosilica in concrete” Journal of the Transportation Research Board, 2010: 2141, pp. 6-9). It was observed how the addition of nano-and microsilica causes an increase in the density and compactness of C-S-H gels, in addition to modifying their morphology. There were also decreases in the amount, size and crystallinity of the portlandite, and refinement of the porous structure. When the addition used is microsilica, percentages close to 10% are necessary for significant improvements in the mechanical behavior of the materials with respect to the references used, of the order of a 30% increase in compressive strength values (the values 15 obtained will depend on the dosages used) (Nazari, A., Riahi, S., “The effects of SiO 2 nanoparticles on physical and mechanical properties of high strength compacting concrete” Comp. B, 2011: 42, pp. 570-578). However, the incorporation of nanosilica allows to increase the values of said parameter up to 60%, with lower addition percentages being sufficient. The incorporation into concretes, with an aggregate / cement ratio of 0.3, of up to 10% by weight of 20 micro-silica modifies significantly the porous structure (28% decrease in total porosity), with respect to the reference sample at relatively low curing ages, the improvements for 90 days of curing being less important (Poon, CS, Kou, SC, Lam, L., “Compressive strength, chloride diffusivity and pore structure of high performance metakaolin and silica fume concrete” Cons. Build. Mater, 2006: 20, pp. 858-865). In order to increase the pozzolanic activity and to improve the porous structure and durability to a greater extent, nanosilica additions are currently being used, making it clear that their use leads to greater improvements than that of microsilica. For example, the incorporation of 5% nanosilica allows to increase the electrical resistivity by 30% and by 50% the resistance to the penetration of chlorides, after 7 days of curing (Madani, H., Bagheri, A., Parhizkar, T., Raisghasemi, A., "Chloride penetration and electrical resistivity 30of concretes containing nanosilica hydrosols with different specific surface areas" Cem. Concr. Comp, 2014: 53, pp. 18-24). On the other hand, it has been described that the provision of 5% nanosilica in mortars translates into a 70% increase in resistivity and a 80% decrease in the chloride migration coefficient (Zahedi, M., Ramezanianpour, AA , Ramezanianpour, AM, "Evaluation of the mechanical properties and durability cement mortars contanining nanosilica and rise husk ash under 35chloride ion penetration" Cons. Build. Mater, 2015: 78, pp. 354-361) .The effectiveness of using nanoparticles of silica in the improvement of the properties of concrete and mortars depends on many factors such as: the proportions used, if they are added additionally or substitute for any of the components, the stage of incorporation, the type of mixing, the prior preparation process, the state of agglomeration, size and structure, etc. As an example of the difficulties in standardizing the methods of preparation of cementitious materials that incorporate na noparticles, a lack of clarity is common when describing occasions when an “in dry state” dispersion is performed, but without reference to a prior thermal conditioning. In the state of the art it is usual to refer to the dry state, calculated as the weight of the material in the absence of moisture, to formulate the dosage of the materials, but for practical reasons the materials in large volumes do not undergo prior drying processes for economic cost since water is added as a necessary stage in obtaining mortars and / or concrete from cement. Inorganic solids “in a dry state” have a proportion of absorbed water that depends on the relative humidity of the air, the temperature, atmospheric pressure, nature of the surface of the solid and specific surface. It is expected that in a scientific work on this technology it will be explicitly explained if there is a complete absence of moisture since it implies an added complication in the handling of the powder material. Completely dry materials are more volatile by increasing their loadelectrostatic and also present explosion risks. In the case of nanoparticles, these effects are magnified. In addition to the properties of the materials obtained, cost is another critical factor in the field of construction. The more preparation steps these mortars and concretes have, the more expensive it will be to manufacture, thus increasing both the complexity in the production of materials and the cost of them. In general, all the improvements are focused on achieving a percentage improvement of the properties that in no case would allow more than double the useful life of the cementitious material. To achieve improvement effects, highly complex and expensive highly additive compositions are required. Therefore, materials that significantly increase the useful life of the materials are required in an effective and simple and economic methodologies.10 In addition, a particular case of the limitations of the state of the art for increasing durability is the formation of expansive products from the hydrated phases. Specifically, the evolution of the first formed etringite (primary etringite) towards calcium monosulfoaluminate leaves open the possibility of reaction with external sulfates and subsequent formation of the etringite phase (secondary etringite), generating very significant increases in volume in the hardened state, producing significant internal tensions and cracking. This effect causes a significant deterioration of the mechanical and durable properties of cementitious materials, significantly reducing their service life. In the state of the art, this process is attempted to control through the use of decentments with low aluminate content and / or the use of additions such as slags or fly ash. The limitation of aluminates in cements complicates the manufacturing process thereof and limits some of the characteristics of the material. In the case of the additions, its use is currently limited by the reduction of availability.Therefore it is necessary to obtain cementitious composites for the improvement that the characteristics of mortars and concrete where: 25e the effective incorporation of the nanoparticles and / or microparticles is carried out in the Mortar and concrete preparation processes. Specifically in nanoparticles their nanometric dimension causes diffuse emission of nanoparticles that on the one hand prevents their control and on the other generates environmental problems. Certain dimension implies a high volatility since it causes the presence of clouds of nanoparticles difficult to control. Additionally, the high specific surface area of the nanoparticles causes a state of agglomeration thereof that to date is only partially solved by dispersion in liquid suspensions, for example aqueous. The use of nanoparticles generally involves the use of chemical additives of polymeric type which improve rheology 35 to ensure the workability needed in this type of material  Simplify the number of unit operations and components to optimize costs. The high price of nanoparticles, their low effectiveness due to agglomeration and the complexity of handling imply a high number of unit operations required for their use. Complexity in use implies processes that increase the final cost and therefore restrict its use for very specific applications. • The risks of handling nanomaterials are reduced. The high reactivity of the nanoparticles poses a potential danger to their use, given the proven absence of nano-toxicology studies, which imply restrictions in their handling such as the use of personal protective equipment that are not common in the construction sectors to which Mortars and concrete are intended. The durability of the resulting materials is improved. It has not been demonstrated that simple methods of use of nanoparticles can be used for the generation of cementitious materials, in particular for use in applications requiring periods of useful life exceeding 100 years. For this case a long durability of the materials is necessary, which results in a greater sustainability of the construction processes. The main limitation of durability is the connectivity and size of the porous network, through which external aggressors that affect the cement matrix and the steel embedded in the structural concrete access. Historically, additions areThey have used to refine the porous structure. However, currently, the necessary increase in useful life of the structures demanded by technical requirements in search of greater sustainability makes cementitious materials necessary with significant improvements in this aspect. 5 Definitions For clarity some definitions are introduced: - "cement" refers to a mixture of calcium silicates and aluminates, obtained through the cooking of calcareous, clay and sand. The material obtained, ground very finely, once mixed with water, hydrates and solidifies progressively. Cements can be of clay origin and obtained from clay and limestone; or of pozzolanic origin. These are industrial products that have different nomenclatures according to national employment standards. - “cement particles” or “cement microparticles” refers to cement in powder form with sizes between 1 µm and 500 µm .- "cementitious composite or cementício" is defined as a mixture of materials that contain 15 cement particles and react hydraulically in the presence of water. - "silica nanoparticles" sedefinencuando at least 50% of the silica particles have a size less than 100nm .- "microsilica" and "silica microparticles" are used interchangeably, and refers to an agglomerated silica material that It comprises silica nanoparticles and is transported as a micrometric material due to its state of agglomeration. In the present invention, the term "silica nanoparticles" will be used to refer to silica particles with at least 50% particles with a size less than 100 nm that are forming strongly cohesive agglomerates defined as silica microparticles, or microsilica, or microsilica, or if they have formed little cohesive agglomerates defined as 25nanosílice, or silica smoke - silica fume -. In other words, whether we talk about: - silica particles of dimensions of the order of nanometer disperses - that would be nanoparticles themselves - , as if we were talking about - silica microparticles - which would be agglomerated nanoparticles and therefore in the form of particles that can be of micrometric dimensions - 30 we will refer to them as “silica nanoparticles”. - "superplasticizer" and "superfluidifier" are used interchangeably. - "dispersion" refers to the spreading of a substance within another that is much more abundant than the first.The term chemical dispersion refers to a colloidal dispersion is a physicochemical system formed by two or more phases: one continuous, normally fluid, and another dispersed in the form of generally solid particles, between 5 and 200 nm. In the state of the art the term dispersion does not establish a parameter to determine the degree of dispersion, as occurs in mathematics, where it refers to the degree of distancing of a set of values from its average value. In the state of the art the term dry dispersion refers to a dispersion of solid particles, between 5 and 200 nm, in other solid particles, greater than 100 nm. If the nanoparticles represent the dispersed phase, the state of the art also uses the term "nanodispersion" .- "dry" or "dry" material refers to a material that does not contain added water. The water content in a solid material is determined as the amount of water contained in the solid referred to the wet solid (dry solid plus water). Material "without absorbed water" refers to a dry material that is not in equilibrium with the partial vapor pressure of the water contained in the air and that maximizes the water vapor absorption capacity. When a substance is exposed to the air (unsaturated) it will begin to evaporate or condense water in it until the partial pressures of the water vapor contained in the air and the liquid contained in the solid equalize. ForAt a given temperature, the equilibrium moisture of the solid will therefore depend on the relative humidity of the air. - "Durability" of the concrete refers to the ability of the concrete to resist weathering, chemical attack, and abrasion while maintaining the At the same time its desired engineering properties. Different concretes require different degrees of durability depending on the exposure environment and desired properties. DESCRIPTION OF THE INVENTION The present invention still relates to a new cementitious composite and a new type of cementitious materials of the mortar and concrete type with long service life comprising submicronic crystals of etringite and portlandite after the material cure period. Said crystals have submicron dimensions in at least one of their dimensions, <300 nm, preferably <200 nm, and more preferably of <100 nm and more preferably still of <50 nm, and remain stable after 28 days of material cure, and more preferably after 90 days of material cure. In this invention, two additions have been used in the examples for the formation of cementitious composites: a) Microsilica: this compound is generated as a by-product during the reduction of high purity quartz with coal in electric arc furnaces to obtain silicon and ferrosilicon. It consists essentially of non-crystalline silica with a high specific surface area 20 compared to that of Portland cement. The average particle size is micrometric and corresponds to agglomerates of silica nanoparticles. At least 50% of the particles are smaller at 100 nm and contains silica particles up to 1000 nm. The state of agglomeration is such that the presence of silica particles or nanoparticles outside the agglomerates is insignificant. 25b). Nanosíliceo silica fume: it is a synthetic form of silicon dioxide characterized by the nanometric dimension of its particles.The material is agglomerated but the agglomerates are little cohesive and with different sizes of agglomerates ranging from nanometric to micrometric sizes.The physical phenomenon The present invention is based on the dispersion and anchoring of nanoparticles30 of oxides of different nature on cementitious microparticles forming cementitious composites. This dispersion process takes place by the establishment of interaction forces between the surface of the particles involved, such as Van derWaals forces, are the attractive or repulsive forces between molecules (or between parts of the same molecule) other than those due to an intramolecular bond (ionic bond, metallic bond and covalent bond of reticular type) 35o to the electrostatic interaction of ions with others or with neutral molecules. Van der Waals forces include: force between two permanent dipoles (dipole-dipole interaction or Keesom forces); force between a permanent dipole and an induced dipole (Debye forces); o Force between two instantaneously induced dipoles (London dispersion forces). In the dispersion process the proximity interactions between the surfaces of the nanoparticles and the microparticles 40 provide a modification of their surface characteristics that allow the anchoring of the nanoparticles on the surface of the microparticles and the resulting composite has an improvement in functional properties. The oxides have differences in the adsorption of OH-groups from the dissociation of waterborne molecules at the available surface sites of the particles. This characteristic of adsorption of OH-groups is defined as the basicity of the surface quantitatively indicates the ability to give electrons from oxygen ions, O2-, and the adsorption of OH-on the surface of the oxide. The absorption capacity of OH-groups on the surface of the oxides is increased with the reduction of the particle size and produces an increase in the electrostatic charge of these particles. When H2O saturation occurs in the atmosphere, 50-water molecules are formed on the surface of the particles that contribute to the neutralization of the charge.The invention contemplates a pre-drying process of silica nanoparticles (when referring to "silica nanoparticles", both nanosilica and microsilica - agglomerated nanoparticles are being mentioned, as explained in the "definitions" section) to maximize Electrostatic charge of the nanoparticles and favor van der Walls interactions with the surfaces of the cement particles. In this way the repulsion between the silica nanoparticles 5 and the anchoring of these in the cement particles occurs, thus forming the dispersion of the silica particles.The anchoring of the silica nanoparticles on the surface of the cement microparticles is favored by load compensation between micro and nanoparticles. In this way the moisture absorption capacity of the composite thus formed is modified. The invention contemplates a process for obtaining cementitious composites comprising the dry dispersion of silica nanoparticles, at a humidity less than 0.3% in weight relative to the total weight , preferably less than 0.2%, more preferably at a humidity less than 0.1% and more preferably even at a humidity less than 0.05% by weight with respect to the total weight, on the cement particles. This dispersion allows the arrangement hierarchical of the particles where the nanoparticles that present a smaller proportion are dispersed on the surface of the 15 cement microparticles that are in greater proportion. The micrometric size of the cement particles defines the surface available to house the nanoparticles. This mixture is used as a conventional cement with good workability in the preparation of mortars and concrete, which refers to the ease with which an operator can handle the mixture and is determined with the degree of fluidity. The degree of fluidity has been measured with the Abrams cone and is reflected in Table 8. It is proposed to use this mixture, cementitious composite, for mortars and concretes with long-lasting properties in service with durability and high resistance to environmental agents. The present invention is It refers firstly to a process for preparing a composite cement that comprises: 1) a first stage of conditioning nanoparticles of silica, selected from microsilica, nanosilica and mixture of both, in which they are heated to a temperature between 85-235 ° C, preferably between 130 and 230 ° C, more preferably between 90 and 140 ° C, and more preferably even between 95 and 110 ° C for a sufficient time interval To achieve a maximum moisture percentage of 0.3% with respect to the total weight of the material resulting from this first stage, 2) a dry dispersion stage in which the particles conditioned according to stage 1) are dispersed on cement and in the that inert grinding balls are used, 3) a conditioning stage of the cementitious composite obtained in stage 2), in which the grinding balls used in the preparation of the cementitious composite are separated, for example, a sieve. silica nanoparticles depend on the temperature chosen and the amount of nanoparticles, that is, the volume of available material. The time will therefore be necessary to obtain a maximum humidity percentage of less than 0.3% by weight with respect to the total weight of the material resulting from said first stage, preferably less than 0.2%, more preferably at a lower humidity of the 0.1% and more preferably even at a humidity of less than 0.05%, on the cement particles.According to specific embodiments of the process, this comprises: 1) a first stage of conditioning of silica nanoparticles, in which they are heated at a temperature between 85-235 ° C, preferably between 130 and 230 ° C, more preferably between 90 and 140 ° C, and more preferably even between 95 and 110 ° C for the time necessary to obtain a maximum moisture percentage of 0.05% with respect to the total weight of the resulting material, 2) a dry dispersion step, in which the silica nanoparticles conditioned according to step 1) are dispersed on cement and in which inert grinding balls are used e zircona 50 stabilized with ytria of 2 mm in diameter,3) a stage for conditioning the cementitious composite obtained in stage 2), in which the grinding balls used are separated from the cementitious composite obtained using, for example, a sieve with 500 µm mesh light. The silica nanoparticles - as defined above in the "definitions" section - according to the invention can have an average size of between 0.08 and 20 µm, preferably between 0.1 and 18 µm, more preferably between 0, 2 and 15.0 m. The nanosilica particles may have an average size between 0.08 and 0.4 µm, preferably between 0.2 and 0.3 µm. The microsilica particles may have an average size between 10 and 18 µm, preferably between 12 and 15 µm. Silica nanoparticles - as defined above in the "definitions" section - according to the invention can have a specific surface BET between 15 and 220 m2 / g, preferably between 1020 and 210 m2 / g, more preferably between 23 and 200m2 / g. The nanosilica particles may have a specific BET surface area between 15 and 25 m2 / g, preferably between 20 and 23m2 / g. The microsilica particles may have a specific BET surface area between 160 and 220m2 / g, preferably between 18 and 200m2 / g. According to specific embodiments of the process, step 1) of conditioning the raw materials comprises heating silica nanoparticles, at a temperature between 100-200 ° C for a period of, for example, between 22 and 26 hours.According to additional concrete embodiments of the process in the first stage the particles are heated between 100 and 140 ° C, for a time interval, for example, between 23 and 25 hours. The purpose of this first stage of the process is to achieve optimum heating of the powder sample so that adsorbed moisture is removed. Therefore, any heating system that meets this condition could be used. The equipment for performing this stage may be, for example, a drying oven, such as a horizontal forced air drying oven from Labopolis Instruments. Any device or equipment that allows continuous microwave drying or infrared oven drying can also be used.25 In the first stage the nanoparticles can be heated following ramps between 1 ° C and 100 ° C / min, preferably between 3 ° C and 50 ° C / min. According to specific embodiments of the process, in the first stage nanoparticles are obtained with a humidity percentage less than 0.3% in weight relative to the total weight, preferably less than 0.2%, more preferably at a humidity less than 0.1% and more preferably even at a humidity of less than 0.05% by weight with respect to the total weight, on the cement particles, later, once obtained, the moisture absorption capacity of the nanoparticles that are anchored is modified because they have compensated the surface loads, thus affecting same to the surface of the cement particles. Therefore, the moisture does not have the same effect on the composite once obtained as on the individual components thereof.35 In step 2) of the process the silica nanoparticles and the cement can be in a variable weight proportion, for example of between 85 and 99.5% of cement and between 15 and 0.5% of particles. This process of dispersion of the particles on the cement is assisted by inert demolition balls that can be of variable diameter, and whose function is to favor the transfer of energy between the particles.40 According to particular embodiments of the invention, in stage 2) of dispersion in dry, the appropriate amount of raw materials - silica cement and nanoparticles (selected from microsilica, nanosilica and mixtures thereof) - necessary to form the composite, previously conditioned particles according to stage 1), are introduced into a biconic stirring mixer where some particles impact with others. The impacts that occur between the particles in the absence of absorbed water are those that provide the energy necessary to establish the short-range interactions between the cement particles that constitute the support particles, which are the cement particles, and the nanoparticles so that they are dispersed and anchored in the larger ones. The equipment for carrying out the dispersion stage 2) can be, for example, a mixer such as a concrete mixer or mixer, V powder mixer, drum, free fall mixer, 50when a part of the addition is nanosilica, even in small proportions, the upholstery of pores with stable etringite of stable nanometric size increases after the curing of the mortar which is advantageous for the durable properties of said materials. Example of this are the excellent properties found for the case of 8% microsilica + 2% nanosilica, especially in regard to durable aspects, for which 5 very high resistivity values (81.8 kΩ.cm) and an extremely high chloride migration coefficient are obtained low (0.761 x 10-12m2 / s). The method of the present invention, by dry dispersion, is a very effective method of preparing cement-based materials, especially as regards the durable properties. In addition, it is a method that guarantees hygiene and health at work, avoiding the harmful effects that inhalation of such small particles can cause when the silica nanoparticles are anchored in the cement microparticles. In this way, the cementitious composite of the present invention can be handled and used as a standard cement without special nanomaterial handling requirements.The presence of primary etringite in the cement-derived materials of the present invention after curing, allows to achieve characteristics in the material they represent. significant advantages such as the following values in standardized mixtures: • Reduction of the connected porosity with total porosity values below 10% • Acceleration of the pozzolanic reactions at low curing ages with higher percentages of CSH gel.20 • Better adhesion between aggregate and cementitious paste • Fast hardening with values of up to 60 MPa at 7 days for mortars from cementitious composites using the invention with 52.5R cements and up to 80 MPa at 7 days for mortars from using the invention with CEM I 52.5 R cements in standardized mortars (relative water / cement ratio equal to 0.5) 25 • Values of up to 80 MPa at 28 days for mortars from resistant class 52.5R cements and up to 100 MPa at 28 days for CEM I 52.5 R cement in standard mortars (ratio water / cement equal to 0.5) • Applicable to mortars and / or concretes • Long durability of concretes with very high resistivity values (81.8 kΩ.cm) and an extremely low chloride migration coefficient (0,761 x 10 -12 m2 / s). • Long service life of concrete with values calculated over 800 years • It adapts to different types of cements • It combines the incorporation of micro and nanoparticles of different nature in a simple single-dose cement process that minimizes the handling variables by operators .35 • Reduces costs by allowing the use of nanoparticles in standardized processes with the production of cement particles • High workability in forming mortars with absence of organic additives such as superplasticizers and in concrete with reduction of organic additives such as superplasticizers.40 • Method that guarantees Hygiene and health at work, avoiding the harmful effects that inhalation of nanometric particles can cause. Brief description of the figures: Figure 1 shows micrographs of scanning electron microscopy MEB of cement 52.5 R.45Figure 2 shows SMB micrographs of the cementitious composite of the invention with 10% nanosilica Figure 3 shows SMB micrographs of cement with 10% FE, this is 10% micro silica from Ferroatlántica S.L. Figure 4 shows the MEB micrograph of the sample of mortar M-3.2 at 7 days of age of cure, where the inside of a pore covered with nanometric etringite can be seen. Figure 5a), 5b) and 5c) show they present the M-3.2 micrographs of M-3.2 mortars at 28 days of age of curing with different scales, where you can see the inside of a pore clearly upholstered by nanometric etringite particles that remain stable. Figures 6a) and 6b) show micrographsMEB for the dosing of the concrete in sample H-3.1 10a after 28 days of curing, in which it is observed that the reduction does not occur when the addition is micrometric in size. Figure 7 shows the MEB micrograph of the H-3.3 concrete after 28 days of curing, where nanometric etringite aculas can be seen. In Figure 8 a) and 8b) the etringite crystals are observed next to the C3A formations, on a MEB 15 micrograph of H-3.2 concrete after 28 days of curing. Figure 9 shows a 90-day H-1 DRX diagram with a percentage of Etringite of <0.5% with respect to the total mass. Figure 10 shows a 90-day H-3.1 DRX diagram with a percentage of Etringite of 1.6% with respect to the total mass.20 Figure 11 shows a DRX diagram of H-3.2 at 90 days with an Etringite percentage of 2.4% with respect to the total mass. Figure 12 shows a DRX diagram of H-3.3 at 90 days with an Etringite percentage of 1.5% with respect to The total mass. 25 EXAMPLE EXAMPLE 1. PREPARATION OF CEMENTICE COMPOSITE Table 1 shows the physical and chemical characteristics of the cement used, provided by the manufacturer. Table 2 shows the granulometry of said cement. Table 1. Physical and chemical characteristics of the cement used30 Chemical characteristics (%) Results Standard EN / UNEP lost by calcination / Lost to fire1,60 <5 Insoluble Residue 0.3 <5 Sulfates (SO3) 3.10 <4 Chlorides 0.01 <0.10 Physical and mechanical characteristics Water of normal consistency% 35.3 Principle of setting 90> 45 End of setting 127 <720 Le Chateliermm extension 0.8 <10 Specific surface (Blaine) cm2 / g7470Table 2. Granulometry of the cement used5 The following table 3 shows the specific surface area and the average particle size.Table 3. Specific surface area and average particle size of the additions usedNanosilicaMicrosilicateSpecific surface area BET (m2 / g) 20023Average size (m) 0.2-0.315.01-drying of the silica nanoparticles10 In a specific example, 200 grams of nanosilica or microsilica, or a mixture of both are heated at a temperature between 100-200 ° in the raw material conditioning stage C, preferably 120 ° C, for 24 hours, in order to remove the adsorbed moisture in the silica nanoparticles. This stage is critical for the adequate dispersion and anchoring of smaller particles.15 In another conditioning stage test it has been found that 1 gram of nanosilica, or 1 gram of microsilica, or a mixture of both, effectively dried in heating at 120 ° C for 5 minutes with ramps of 20 ° C / min on an infrared scale. Similar treatments at 140, 160 and 180 ° C for a similar time have given the same result but require energy consumption and energy to heat the material. 20 The preferred conditions for some embodiments were 100 ° C -24 hours. In other examples the cement microparticles were also dried. However, this process is not necessary and it was possible to verify that the same results were obtained without the drying process of the cement particles since the water absorbed in the cement is not removed by drying since it reacts forming hydrated compounds. Granulometry (% passing) Screen 1 Micron 14.0 Screen 8 Micron 61.0 Screen 16 Micron 88.0 Screen 32 Micron 99.8 Screen 64 Micron 100 Screen 96 Micron 100 Average diameter (micron) 5.72. Dry dispersion process: In a specific example, 90% proportions of CEM I 52.5 R cement particles and 10% nanosilica or microsilica cement, or 10% of a mixture of both are used; for example, 8% of microsilica and 2% of nanosilica. The adequate amount of raw materials necessary to form the composite, previously conditioned the silica nanoparticles, is introduced into a biconic agitator mixer where some particles impact with others. This stirring process is assisted by inert grinding balls of stabilized zirconia with a 2 mm diameter ytria that helped to generate a greater transfer of energy between the particles. The weight ratio between grinding balls and the cement particles used was 1 to 2. 10 A 10 L biconic mixer with a useful capacity, built in AISI-316-L stainless steel, was used for all parts in contact with the product . The mixer was mounted on a carbon steel bench, sized to allow a useful distance from the discharge valve to the ground of 800 mm. 153. Conditioning of the cementitious composite: At this stage, the grinding balls were separated from the product by means of a 500 µm vibrating plate made of stainless steel light mesh, which ensures that the finished product does not contain grinding balls and also allowed to reduce the possible agglomerates formed due to the stirring of the materials in the mill to release said agglomerates.20 The stage of conditioning the final product or product obtained in stage 2) of dispersion has been carried out, using a circular sieve for classification of solid products of Labopolis Instruments, suitable for sieving from 36 µm up to 25 mm. The sieve has a product inlet through the central part and outlet through the side mouth and is made entirely of stainless steel. It has a vibrating motor with eccentric masses. 25 The product has been screened until the grinding balls used are clean and all the agglomerates have been discarded. Optionally, the balls can remain inside the mixing system if a suitable separating element is available that allows the exit of the composite microparticles and retaining the microballs. 30 Example 2. PREPARATION OF MORTAR USING CEMENTICE COMPOSITE For the preparation of mortar specimens CEM I 52.5 R cement was used, supplied by the Portland Cement Valderrivas Cement Group and manufactured in accordance with the standard (UNE -EN-197-1: 2011). The characteristics of the cement used are shown in Table 1 and 2 above. Two different additions have been used for mortars. Microsilica supplied by Ferroatlántica SL and nanosilicate powder CAB-O-SIL M-5 supplied by CABOT. The aggregate used to manufacture the mortar specimens was a CEN standardized sand complying with the specifications of the standard (UNE-EN 196-1 2005 ) .40 For standard mortar tests, standard 40 x 40 x 160 mm prismatic specimens were manufactured. The manufacture of these mortar specimens was done according to the procedure described in the standard (UNE-EN 196-1, 2005) with the exception of compacting the samples for which 90 strokes were used. The amount of cement and the water / cementitious material ratio (a / c) is 0.5, the one specified in the same standard. In the cases in which nanoparticle additions were introduced to obtain the composite, the amount of cement was considered cementitious composite, that is, the nanoparticles replace the cement. Thus the water / cementitious composite ratio was maintained with a value of 0.5. After 24 hours in the mold in a laboratory environment covered by a damp cloth to avoid drying, the specimens were unmold and cured submerged in water keeping it at (20 ± 1) ºC. 50Two methods of incorporating the nanoparticles into the mixture were compared. The first was to add the nanoparticles during the kneading process; that is, the conventional method called as a manual method of incorporating nanoparticles. In the second method the nanoparticles were added using the method object of the present invention described above in the "description of the invention" section and the examples of preparation of cementitious composite, which achieves a dry dispersion of the nanoparticles on the cement particles. This mixture is used as a conventional cement with good workability in the preparation of mortars and concrete. Dosages with different nanoparticle content were tested. In conventionally prepared dosages for comparative purposes it was necessary to add a superplasticizer additive to improve the handling of mortars. The best results in mechanical and durable properties were obtained for dosages with 10% nanoparticles, the optimum being found in the durability properties in the combined addition of microsilica and nanosilica, in proportions of 8% micro and 2% nanosilica. This mixed addition dosage was only possible with the material obtained using the method of the present invention, since manual mixing was impossible given the enormous demand for water that it required. In the manual mixing it was not possible to avoid the use of the superplasticizer additive in proportions of less than 5% with respect to the weight of cement that allows, at most, the norm. The mixture made by the manual method of incorporating nanoparticles, even with the maximum content of superfluidifying additive, proved impossible to knead. Following the conventional method of adding 20nano silica particles it was only possible to mix with a 10% addition of microsilica. In the following, the results of the different tests of mechanical and durable properties that have been carried out will be presented, for the following dosages: -M1, reference dosage made with CEM I 52.5 R cement without any addition.-M2 , conventional dosing with the same cement and manual addition of 10% 25 microsilica.-M-3.1, dosing with the same cement and adding 10% dispersed micro silica with the method of invention.-M-3.2, dosing with the same cement and addition of 8% micro silica and 2% nano silica dispersed with the method of invention30-As the main mechanical characteristic of cementitious materials, compression strength is used. The compressive strength test was performed according to the standard (UNE-EN 196-1, 2005). At the ages of 7 and 28 days, six semiprisms previously obtained from the flexural fracture of 3 4x4x16 cm specimens of each of the prepared dosages were broken. The test machine used was a 150 T hydraulic press Ibertest brand with Servosis automation. The results found for this mortar test are shown in Table 4: Table 4. Compressive strength at 7 and 28 days of the dosages used Sample Compressive strength at 7 days (MPa) Compressive strength at 28 days (MPa) M- 159 ± 267 ± 1M-262 ± 380 ± 1M-3,181 ± 397 ± 4M-3,277 ± 389 ± 2 As can be seen in Table 4, the additions of microsilicate and nanosyellate improve the mechanical properties with respect to the mortar without addition used as reference. The improvement is superior in the case of the use of the materials object of the invention. In this property, the mortar made with 10% microsilica presents better results, reaching 100 MPa in some samples made with the cement prepared with the particle dispersion method of the presentinvention. This method represents an improvement over 20% on samples made with the same amount of addition incorporated manually. In the case of the dosing carried out with mixed addition of microsilica and nanosilica with the method of the invention, lower values were obtained than for the 10% of microsilica added also with the method of invention, but higher than the mixture in which it was added manually . On the other hand, in the measurements of 5 durable properties, better results were obtained in the M-3.2 mortar. The fundamental parameters measured to assess the durability of the samples were electrical resistivity and chloride migration. Table 5 shows the average values of the cell constant (K), electrical resistance (Re) and electrical resistivity (e) for the mortar specimens selected at the cure age of 7 and 28 10 days of cure. In addition, the risk of chloride penetration is included for the calculated average value of electrical resistivity because both parameters can be related. This correlation can be obtained from the chloride penetration risk data dictated by ASTM C12012.Table 6 shows the chloride migration coefficient (Dnssm) at the age of 28 days for selected mortars.15 5. Average values of the cell constant (K), electrical resistance (Re), electrical resistivity (e) and risk of chloride penetration for the selected mortar specimens at 7 and 28 days of curing. Sample K = S / L ( cm) Cured age (days) Electrical resistance (kΩ) Electrical resistivity (kΩ.cm) Penetration risk Cl-M-15.1070.7283.71 High280.8174.17 High H-25.6171.1356.40 Moderated 282.07511.6 Low M-3.15.9970, 8234.93 High 283.30022.02 Low M-3.25.9073.91523.1 Very low 285.46032.2 Very low Table 6 shows the migration coefficient of chlorides (Dnssm) at the age of 28 days 20 for selected mortars Table 6. Coefficient Chloride Migration (Dnssm) after 28 days of cure for mortar Selected samples Dnssm (10-12.m2 / s) M-113,687M-24,862M-3.12,879M-3.22,476 Through the scanning electron microscopy technique, MEB, the 25 different mortars prepared at the age of 7 were analyzed and characterized 28 days of cure. In these samples the different hydration products of the mortars were also identified. The morphology of the originated C-S-H gels, the phases of the interior of the pores, as well as the morphology and phase sizes such as portlandite and etringite were studied. In addition, the changes caused by incorporation have been studiedof the additions to the matrix of the mortar samples and the ozone transition interface (ITZ) between the aggregate and the paste of the samples.In the cementitious materials of the mortar type proposed by the present invention, in the case of the addition of nanosilica , there are nanocrystals of etringite and portlandite originated during the hydration of the material. The permanence of nanometric crystals of Etringite covering the pores of the hardened material represents a significant advantage, both in the face of stability against sulfate attacks and in the presence of aggressive substances through the porous network. In this way, a mortar with exceptional durable characteristics and therefore with a very long expected life is obtained. Figure 4 shows the MEB micrograph of the M-3.2 sample at 7 days after curing, where the interior of an interior can be observed. pore upholstered by nanometric etringite.10 In Figure 5a) b) and c) the MEB micrographs (of sample M-3.2) are presented at 28 days of age with different scales, where the inside of a pore can be clearly seen upholstered by nanometric etringite particles that remain stable.For mortars made from cementitious composites of the present invention, prepared with additions of nanoparticles on anhydrous cement CEM I 52.5 R, it is observed that: 15 • All increase their resistance values Compressive with respect to the sample without additions used as a reference, as well as on samples in which the addition of nanosilica and microsylic has been carried out in a c Onventional, the best being 10% micro-nanosilica, and 8% micro-silica + 2% nanosilica at the age of 28 days of cure • All lead to higher percentages of degree of hydration and CSH gel, with the general trend being the descent of the Dehydroxylation percentages • A refinement of the porous structure is obtained in all cases with lower values of the migration coefficient of chlorides and higher electrical resistivities • In the scanning electron microscopy (SEM) images, more compact and dense gels are observed than in the cement reference mortar CEM I 52.5 R without additions, as well as a better adhesion between the paste and the aggregate. In the nanosilica samples, a nanometric etringite upholstery is observed in the internal pore walls that does not appear for the microsilica or in the reference mortar.It emphasizes that for 28 days of curing the nanometric etringite phase remains unchanged. This effect is particularly notable, as it demonstrates that this phase does not degrade, so it is an improvement in durability against sulfate attack. Usually the primary Etringite phase formed during the hydration of the cements is not stable and goes into a state of monosulfate, with less sulfate content, thus being susceptible to being attacked by the entry of sulfates from the outside, reacting with it to give again calcium trisulfoaluminate hydrated in a hardened state, what is called secondary etringite. The formation of secondary etringite produces a large increase in volume inside the hardened material, an effect that causes large internal stresses, and as a result causes significant cracking and degradation of the material. Example 3. 40 PREPARATION OF CONCRETE USING COMPOSITE CEMENTICE To manufacture the specimens Three concrete dosages were selected among those that gave better results than those studied in paste and mortar. These were prepared with the same cement (CEM I 52.5R). In addition, a concrete with cement alone was prepared for use as a reference (H-I) against the mixtures under study. The following compositions were the following, in all those that had addition, this was incorporated by the method of the present invention: -H1, reference dosage made with CEM I 52.5 R cement without any addition.-H3.1, dosage with the same cement and addition of 10% microsilica.-H3.2, dosing with the same cement and adding 8% microsilica and 2% nanosilica-H3.3, dosing with the same cement and adding 10% nanosilica.Table 7 shows the dosages used for the manufacture of concrete specimens.Table 7. Dosing for a cubic meter of concrete of the concrete under study5Materials (kg / m3) H-1H-3.1H-3.2H-3.3CEM I 52.5R CEM U 400360360360Microsílice (g ) -4032-Nanosilica (g) - 840 Water (L) 180 180 180 180 Sand (kg) 825825825825 Gravel (kg) 419419419419 Gravel (kg) 524524524524 Superplasticizer (% with respect to the weight of cement) 0.901.001.805.00a / c 0.450.4 / c5.550a / c 0.450a / c 0.450a / c 0.450a / c5.550a / c5.550.450 / c water / cement The processing of these was carried out under laboratory conditions with temperatures of 20-25ºC and an average relative humidity of 35%. The procedure used is that described in the standard (UNE-EN 12390-2, 2009). Prior to weighing the amounts of material indicated for the different dosages obtained, it was necessary to make the appropriate corrections in the aggregates, calculating the humidity at the time of use. Once these values were obtained, the final weights of both aggregates and kneading water were corrected. For the mixing of the materials, a vertical shaft mixer with a capacity of 100 liters provided with a mobile container was used to receive the discharge of the concrete. Once the mixture was homogenized, the anhydrous cement was incorporated with the previously deposited additions. Once the anhydrous cement was incorporated, it was kneaded for 60 seconds with the aggregates to homogenize the material. Then, the additive previously dissolved in a small amount of kneading water was added to the mixture. The remaining water was incorporated slowly. Once the kneading was completed, two types of cylindrical molds were filled in 3 tons with the concrete prepared to obtain cylindrical specimens with a diameter of 150 mm and 300 mm in height and specimens measuring 20100 mm in diameter and 200 mm high. For the compaction of the concrete a vibrating table was used. After 24 hours in a laboratory environment, covered by a damp cloth to prevent drying, the specimens were unmold and cured under water until the ages of 7 and 28 days. Prior to filling the molds, the Abrams cone test was performed, which is a measure of the docility (workability) of the concrete. The results obtained are presented in Table 8.25 Table 8. Abrams Cone Seat for the dosages used Concrete Samples Designation H-1H-3.1H-3.2H-3.3 Seat (cm) 101160 These results show the impossibility of the commissioning of the H-3.3 concrete, due to its null value seat. Table 9 shows the results of the compression test at 7 and 28 days of curing of the manufactured dosages.Table 9. Average compressive strength and its corresponding standard deviation for the concrete under study Sample Compressive strength (MPa) Cured time (days) 728H-1 44.8 ± 3,150.4 ± 1.5H-3.1 46.5 ± 0.256, 3 ± 0.4H-3.2 51.5 ± 5,366.9 ± 0.1H-3.3 49.5 ± 6,152.9 ± 1.1 The compression strength test at the ages of 7 and 28 days of curing on the test specimens Concrete was carried out following the standard (UNE-EN 12390-3, 2009). For the realization of this test, concrete specimens 150 mm in diameter and 300 mm high were used. Table 10 shows the average values of the cell constant (K), electrical resistance (Re) and electrical resistivity (ρe) for the concrete under study at the curing age of 7 and 28 days. In addition, the risk of chloride penetration is included for the calculated average value of electrical resistivity in each case.10 Table 10. Average values of the cell constant (K), electrical resistance (Re), electrical resistivity (e) and risk of Chloride penetration for selected mortar specimens at 7 and 28 days of curing Sample K = S / L (cm) Age of curing (days) Electrical resistance (kΩ) Electrical resistivity (kΩ.cm) Penetration risk Cl-H-13.9571. 2725.02 High / Moderate 282.0908.25 Moderate H-3.13.9372.2028.65 Moderate 2810.58141.58 Very low H-3.23.9374.37017.17 Low 2820.82081.82 Very low H-3.33.9775.93023.54 Very low 287.07528.09 concrete facing low concreteness Chlorides is the determination of the migration coefficient. The concretes under study were subjected to the corresponding test according to the standard NT-BUILT 3040. The results are shown in table 11. They are observed to show the same trends found in the resistivity test, according to these results and applying the life-span models. proposed the EHE (Spanish Instruction of Structural Concrete) and the equivalences between the migration and diffusion coefficients of chlorides, a useful life value is obtained, which is also included in the same table.Table 11. Average value of the migration coefficient of chlorides studied concrete Dosage Migration coefficient 10-12 (m2 / sec) Diffusion coefficient 10-12 (m2 / sec) Useful life (years) (from the start to the beginning of corrosion) H-110,0892,77572H-3.11,910 , 554336H-3.20,7610,271801H-3.32,0170,583319The results by SMB micrographs show that the addition of nanoparticles significantly reduces the size of the crystals. The SMB micrographs presented in Figure 6a) and 6b) for H-3.1 dosing after 28 days of curing, and show that the reduction in crystalline size does not occur when the addition is micrometric in size.5 In Figure 6a) and 6b) SEM micrographs of the H-3.1 concrete are shown. Figure 7 shows the micrograph of the H-3.3 concrete after 28 days of curing, where nanometric etringite needles can be seen. Figure 8a) and 8b) the crystals are observed of Etringite together with the C3A formations of the H-3.2 concrete after 28 days of curing. 10 The micrographs show that the properties of the crystals obtained with the use of nano additions are maintained, improving the microstructure of the material and doubling its life in service. concretes obtained with similar additions of microsilica and nanosilica but following a conventional process for comparative purposes have necessarily had to limit the possibility of mate work rial. It has been impossible to work with nanosilica additions greater than 7.5% with respect to the weight of the cement. Even so, in this dosage, the amounts of superplasticizer additive necessary to obtain adequate workability, exceed the limit allowed by the EHE. Studies conducted on concretes with additions of micro, nano, and mixture of micro and nanosilage that gave better results, indicating that all cases give rise to samples with better mechanical and durable properties than the corresponding conventional concrete used as reference. The improvement of mechanical properties can be related to higher C-S-H gel contents and a higher degree of hydration than the concrete used as a reference. On the other hand, the improvement of durable properties can be related to the formation of a more refined and consolidated porous structure, significantly higher electrical resistivities, migration coefficients of much lower chlorides. It also appears as significant improvements lower percentages of portlandite, 25 which is the hydrated compound most likely to be leached, together with a better adhesion between the aggregate and the paste. In summary, in all of them there has been a notable quantitative leap in the relevant parameters of its potential mechanical properties and especially in the durable ones. With the method of the present invention, concretes having percentages of etringite of at least 1.5% at 90 days have been obtained. 
    权利要求:
    Claims (1)
    [1]
    CLAIMS 1. Procedure for the preparation of a cementitious composite comprising: 1) a first stage of conditioning of silica nanoparticles, in which they are heated to a temperature between 85-235 ° C, for a sufficient time interval to achieve a percentage of maximum humidity of 0.3% with respect to the total weight of the material resulting from this 5 first stage 2) a dry dispersion stage in which the particles conditioned according to stage 1) are dispersed on cement and in which inert grinding balls are used, 3) a conditioning step of the cementitious composite obtained in step 2), in which the grinding balls used are separated from the cementitious composite obtained. 102. Process according to claim 1, wherein in the first stage the particles are heated between 100 and 140 ° C. 3. Process according to claim 1, wherein in the first stage the particles are heated following ramps of between 1 ° C and 100 ° C / min. Process according to one of claims 1 to 3, in which the first stage uses a drying equipment selected from: -drying oven-equipment for continuous microwave drying-equipment for drying in an infrared oven. 5. Process according to one of claims 1 to 4, in which 20 particles are obtained in the first stage with a residual percentage of water of less than 0.2% by weight. 6. Process according to claim 1, wherein in the second dispersion stage the silica nanoparticles and the cement are present in a proportion by weight of between 85 and 99.5% of cement and between 15 and 0.5% of silica nanoparticles .7. Process according to claim 1 or 6, in which a mixer selected from a mixer, a concrete mixer and a biconical mixer is used in the second dispersion stage. Process according to one of claims 1, or 6 to 7, wherein in the second dispersion stage the grinding balls used have a size between 1 mm and 100 mm. 9. Process according to one of claims 1, or 6 to 8, wherein in the second dispersion stage the grinding balls used are selected from YTZ microballs with a diameter of 2 30, ZrSiO4 microballs, and steel microballs, and mixtures of the same 10. Process according to one of Claims 1 or 6 to 9, in which a stirring time between 0.2 and 4 hours is used in the second dispersion stage. 11. A cementitious composite that is obtained according to the process defined in any one of the preceding claims and that comprises 35-cement and -silica nanoparticles in a total proportion of nanoparticles of 0.5% to 15% by weight with respect to cement. 12. cementific according to claim 11, selected from: -a composite that has 8% microsilica and 2% nanosilica, and 40-a composite that has 10% microsilica. 13. The cementitious composite according to claim 11 or 12, wherein the cement is Portland cement.14. A material derived from cement that in its preparation uses the cementitious composite defined in any one of Claims 10 to 13 as the cement phase and that at 28 days of curing also comprises ettringite and portlandite in the form of crystals of submicron dimensions. The material according to claim 14, wherein the submicron dimensions of the ettringite phase comprise sizes less than 300 nm, preferably between 50 nm and 300 nm, in at least one of its dimensions. 16. The cement-derived material according to any one of claims 15-16, which is mortar or concrete. 17. The material according to claim 16, which is mortar and has a compressive strength at 7 days of at least 77 MPa and a compressive strength at 28 days of at 10 minus 90 MPa, an electrical resistivity at 7 days of curing of at least 6.1 kΩ.cm and at least 32.2 kΩ.cm at 28 days, and a chloride migration coefficient at 28 days of 2.47 10-12m2 / s. 18. The material according to claim 16, which is a concrete having a compressive strength at 7 days of at least 52 MPa and a compressive strength at 28 days of at least 67MPa, an electrical resistivity at 7 days curing time of at least 17.17 kΩ.cm and at 15 days at least 81.82kΩ.cm, and a chloride migration coefficient at 28 days of 0.7x10-12.m2 / s.19. Method for the preparation of the cement-derived material defined in any one of claims 12 to 18, comprising a) obtaining a cementitious composite comprising: 20-cement and -silica nanoparticles in a total proportion of 0.5% to 15% by weight relative to cement, preferably from 1% to 12% by weight relative to cement, and a residual moisture percentage of less than 1% by weight relative to total weight, preferably less than 0.5% by weight relative to weight total, and 25b) mixing the cementitious composite obtained with -at least one aggregate, -water -and additional components necessary to obtain a cement derivative. 20. Method according to claim 19, in which the cement derivative is concrete and comprises: 30a) obtaining a cementitious composite comprising: -cement and -silica nanoparticles in a total proportion of 0.5% to 15% in weight relative to cement, preferably 1% to 12% by weight relative to cement, and a residual moisture percentage of less than 1% by weight relative to total weight, preferably less than 0.5% by weight relative to total weight, and b ) mix the cementitious composite obtained with -at least one aggregate, -water -and additional components necessary to obtain concrete, 40c) carry out the operations according to the standard procedure to obtain concrete. 21. Method according to claim 19, in which the cement derivative is a mortar and comprises:b) mix the cementitious composite obtained with -at least one aggregate, -water -and additional components necessary to obtain a mortar c) carry out the operations according to the standard procedure to obtain a mortar, with the condition of using 90 strokes in the compaction of the samples. 22. Method according to claim 19, in which the cementitious composite is selected from: -a composite that has 8% microsilica and 2% nanosilica, and -a composite that has 10% microsilica. 1023. Method according to claim 19-22, wherein the cement is Portland cement. 24. Method according to any one of claims 19 to 23 in which a mortar or concrete is obtained 1525. Use of the cementitious composite defined in any one of claims 11 to 13, or of the material derived from cement defined in any one of claims 14 to 18 in the construction industry.
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    同族专利:
    公开号 | 公开日
    ES2610511B2|2017-10-09|
    CO2018004230A2|2018-07-10|
    US20180244575A1|2018-08-30|
    MX2018003579A|2019-04-25|
    WO2017051052A1|2017-03-30|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    CN101993207B|2009-08-12|2013-01-09|山东宏艺科技股份有限公司|Preparation technology of nanometer SiO2 composite cement|
    US8834624B2|2011-01-26|2014-09-16|Ripi|Modified cement composition, preparation and application thereof|EP3844122A2|2018-09-01|2021-07-07|Dustin A. Hartman|Wear resistant concrete formulations and methods for their preparation|
    CN111925167A|2020-07-29|2020-11-13|昆明理工大学|Mixed crystal nano TiO2Reinforced cement mortar and preparation method thereof|
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    ES201531373A|ES2610511B2|2015-09-25|2015-09-25|PROCEDURE TO PREPARE A MICRO-NANOESTRUCTURED COMPOSITE CEMENTICEO, MORTARS AND CONCRETE LONG-TERM CONCRETE, UNDERSTANDING THAT COMPOSITE|ES201531373A| ES2610511B2|2015-09-25|2015-09-25|PROCEDURE TO PREPARE A MICRO-NANOESTRUCTURED COMPOSITE CEMENTICEO, MORTARS AND CONCRETE LONG-TERM CONCRETE, UNDERSTANDING THAT COMPOSITE|
    MX2018003579A| MX2018003579A|2015-09-25|2016-09-22|Method for producing a cementitious composite, and long-life micro/nanostructured concrete and mortars comprising said composite.|
    PCT/ES2016/070666| WO2017051052A1|2015-09-25|2016-09-22|Method for producing a cementitious composite, and long-life micro/nanostructured concrete and mortars comprising said composite|
    US15/934,084| US20180244575A1|2015-09-25|2018-03-23|Method For Producing A Cementitious Composite, And Long-Life Micro/Nanostructured Concrete And Mortars Comprising Said Composite|
    CONC2018/0004230A| CO2018004230A2|2015-09-25|2018-04-20|Procedure for preparing a cementitious composite, mortars and micro-nanostructured concrete with long service life, comprising said composite|
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