CS254245B1 - Portlaud cement with increased initial strengths - Google Patents

Abstract

The solution relates to Portland cement with increased initial strengths. The essence of the solution is Portland cement made from clinker with a tricalcium silicate content above 56% by weight. and a specific surface area of 250 to 1000 m 2. kg-1 according to Blaina, characterized in that it contains from 0.001 to 1.5% by weight of barium; the dry weight of the reaction product of triethanolamine with hydrochloric acid and 0.1. % to 5 wt. of porous concrete with a content of 11 Atoneborite with a particle size below 00 μιη. Cement with increased initial strength solutions can be used in pre-fabrication, grouting, chimney construction and sliding formwork, in unfavorable paving conditions, in concrete concretes, and in refurbishment work.

Description

254243

The invention relates to Portland cementus increased initial strengths.

Construction practice requires cements with increased initial strengths to produce bees from. increased initial strengths, for the production of concrete at normal temperatures, in accelerating the hardening of concrete by pre-heating and in winter] concreting.

For all these purposes, the cement complies with calcium chloride. However, the calcium chloride additive cannot be used in ferro-concrete because it causes corrosion of the whole reinforcement, (SEBOK, T .: Additives and Preparations for Mortars and Concretes, Prague SNTL 1985, p. 9). blends containing aluminum sulphate additive, (BE-CHYNE, L .: Concrete Technology, SNTL Pra-ha 1954, p. 581) However, fresh cement mixtures with the addition of sulphate of aluminum have a false solidification, (JOISEL, A. : Admix-tures for cement, published by Soiss, France 1973, p. 127), which makes it practically impossible to use them to accelerate the hardness and rupture of strengths. in the altered mineralogical clinker composition compared to ordinary Portland clinker, they are based on the acquisition of active belite clinkers, sulfoaluminium-lithium, halogen-containing saliva, etc. (HOROŠČÁK, T. and KOL .: Researchers) of various types of silicate cements with programmable properties, VÚSH Brno1982). CMS requires new expensive raw materials, their transport and also the modification of technological equipment, respectively. the way of production, often the environmental degradation, which is their disadvantage. The results of suitable additives with a similar effect to calcium chloride have yielded many interesting results, e.g. thiosodium increases the rate of hydration of tricalcium silicate, although not as effective as calcium chloride, (ZLILINSKA, E .: Chem.abstr., 92, 115 370, (1980), the addition of glycerol, triethanolamine and butyl alcohol increases the strength of crystalline neoplasms and their growths, (TAVLINOVA, TI, DOVYBOROVA, LN: Chem. Abstr. 92, 463 339, (1980)).

One of the most promising ways to increase the initial strength of cements is to add seed germs to the cell, which then creates conditions for faster nucleation, formation of more rigid interstices between them, incrementing the basic mass of the microstructure as well as its subsequent gel filling and active reagent in ettringin formation. US-A-771 042 proposes the preparation of crystallization seeds as an additive to increase the strength of Portland cement. Crystallization germs are obtained by quenching Portland clinker in water from 1300 to 1500 ° C at 50 to 100 ° C, holding for 5 to 20 minutes in the wet state and then drying. Under these quasies of hydrothermal conditions, xono-silicate and hydrated form of tricalcium silicate are formed in clinker grains. These are then suitable crystallization centers for the Portland cement hydrate as suggested by the USSR No. 765,227 which proposes the addition of 0.5 to 14 wt. % such. additives to Portland cement.

The drawback of all of the above mentioned ingredients, respectively. Cement designs with increased initial strengths are low efficiency, difficult handling, difficult preparation, dosing problems, high cost.

The above mentioned drawbacks are eliminated by Portland cement. the increased initial strengths of the invention produced from clinker with a tricalcium silicate content of above 56 wt. and a specific surface area of 250 to 1000 m2. kg-1 according to Blaina, characterized in that it contains from 0.001 to 1.5 wt. of the reaction. % triethanolamine product with hydrochloric acid and 0.1 to 5 wt. of porous concrete with a content of 11 Å of thermoset with a particle size below 60 µm. The hydrochloric acid triethanolamine reaction product is prepared by mixing them together, followed by a chemical reaction in aqueous solution at a ratio such that the pH of the reaction product is between 7.5 and 9.0. The advantage of the cement with increased strengths according to the invention is its high initial compressive and flexural strengths compared to Portland cement with the same mineralogical composition and the same grinding fineness. All portland sinters can be used to produce cement according to the invention - it does not require any special and expensive raw materials. The cement according to the invention is produced without modification of the current technological one. equipment and the current technological process.

Both additives are preferably added to the cement grout, which guarantees good homogeneity of all components, and the reaction product of triethanolamine with hydrochloric acid also acts as a grinding intensifier and cementitizer. For the preparation of additives, waste hydrochloric acid and aloes and waste from the production of aerated concrete or aerated concrete from demolition washing machines are used. These additives are not corrosive to the steel reinforcement, are easy to handle, can be dispensed with and are affordable.

Properties of cement so. Example 1 In a MCK 3 laboratory mixer, PC 400 from SC Banská Bystrica, k.

Claims (1)

5 254245 tricalcium silicate was 60 wt. %, specific cement surface 310 m 2. kg "1 Blaina Stage", water and sand in accordance with CSN. The cement side is milled with ground aerated concrete, milled to a particle size below 60 µm. Barbecue additions of an aqueous solution of the reaction product of triethanolamine with hydrochloric acid according to the invention were added to the cutting water. relative to the strength of the table: Table Concentration Concentration Relative strength after 1 day of aerated concrete reaction product bending pressure%%% 0 0 100 100 0.15 0.048 179 167 0.25 0.08 202 183 0.37 0.118 217 188 0.5 0.16 235 171 0.2 0.032 177 156 0.33 0.054 211 144 0.5 0.16 235 171 0.2 0.032 177 156 0.33 0.054 211 144 0.5 0.08 193 142 0.65 0.111 199 136 '0.1 0.064 199 147 0.17 0.105 205 137 0.25 0.16 228 147 0.35 0.21 217 136 Cement with increased initial weather conditions In accordance with the invention, it is possible to use the invention in concrete casting technology, for assembly, These dressings, concrete, construction, or renovation work on chimneys and containers slipformed for operation. OBJECT OF THE PLANT Portland cement with increased amounts of 0.001 to 1.5% by weight. % of dry matter of reaction torque strength made from clinker with triethanolamine product with tricalcium silicate over 56 wt. % by weight and 0.1 to 5 wt. porous concrete and a specific surface area of 250 to 1000 m 2 / kg < 1 > with a 1 A blend of tobermorite according to Blaina, characterized in that the particle size is below 60 .mu.m.