RU2132928C1 - Grouting injection material - Google Patents

Abstract

FIELD: underground construction and mining industry. SUBSTANCE: material contains, wt %: Portland cement 40-43, quartz sand 40-32, and special-destination additive 1.5-3.5. The latter is aqueous solution of Ca(II), Al(III) and chloride ions and also dinaphthalenesulfonate at ratios Ca/Al 5-6, Ca/Cl 0.35-0.45 and (Ca+Al)/dinaphthalenesulfonate 1.3-2.4. EFFECT: accelerated hardening of materials at low positive temperatures and ensured high early strength of hardening material. 1 tbl

Description

 The invention relates to the field of building materials, in particular, to sealing grouting and injection materials, and can be used to fill voids in mine workings, temporary fastening of structures, as well as to reduce deformations of mating structures, buildings, structures and mountain ranges.

 Known sealing grouting and injection materials based on Portland cement, blast furnace slag, gypsum (V.S. Danyushevsky, R.M. Aliev, I.F. Tolstykh. Reference guide for grouting materials, 2nd ed., M., Nedra, 1987, p. 176) based on an astringent and low-basic hydrosilicates, and two-water gypsum and carboaluminate sludge are used as an astringent (A. S. USSR N 1201490, V.I., N 48, 1985). These grouting and injection materials have a slow set of strength and low early strength, especially after 6 to 8 hours of hardening in conditions of low positive temperatures.

 The closest technical solution is Portland cement grouting with additives of setting and hardening accelerator, and calcium chloride 3 - 5%, potassium hydroxide 1.5 - 2.5% and sulfosilicylic acid (SSC) - 0.06 - 0, are used as an accelerator. 01% (V.S. Danyushevsky, R.M. Aliev, I.V. Tolstykh. Reference guide for cementing materials, 2nd ed., M., Nedra, 1987, p. 119 - 121, 178). This material is capable of hardening at low temperatures, but its strength is low, especially after 6 to 8 hours of hardening. This circumstance limits its use in certain mining conditions at low positive temperatures, when it is necessary to obtain significant strength characteristics for 6-8 hours of hardening. Using well-known cement-injection materials, this is impossible to achieve.

This development allows to increase the curing rate of cement-injection material at low positive temperatures (8 ± 2) ^o C, as well as to provide high early strength of the hardened material - after 8 hours of curing not less than 8 MPa.

This is achieved by the fact that the grouting and injection material, including Portland cement, quartz sand and the target additive, as the latter contains an aqueous solution of Ca ²⁺ , Al ³⁺ and Cl ^1- ions, as well as dinaphthalene sulfonate with Ca ²⁺ / Al ³⁺ ratios = 5 - 6, Ca ²⁺ / Cl ^1- = 0.35 - 0.45 and (Ca ²⁺ + Al ³⁺ ) / dinaphthalene sulfonate = 1.3 - 2.4 with the following component ratios, wt.%:
Portland cement - 40 - 43,
Quartz sand - 40 - 43
Target supplement - 1.5 - 3.5
Water - Else
The essence of the technical solution lies in the fact that in the presence of Ca ²⁺ , Al ³⁺ , Cl ^{1 -} and dinaphthalene sulfonate ^ions , complex compounds with the aluminate and ferrite phases of cement are formed, which accelerates the setting of cement hardening at low positive temperatures. In addition, the resulting complexes form crystallization centers during hydration of silicate phases; the introduction of the target additive also increases the dissolution rate of the cement components and increases the rate of hydration of the silicate phases due to a change in pH. The increase in hardening strength is associated with an increase in the reaction surface area, morphological changes, and modification of the crystalline forms of calcium silicate hydrates due to the formation of complex compounds.

 The invention is illustrated by the following examples of specific performance.

 Example 1

Portland cement in an amount of 418 g and quartz sand in an amount of 418 g are mixed until homogeneous, after which 139 g of water are mixed, into which 2.5 g of the target additive is introduced, which ensures a Ca ²⁺ / Al ³⁺ ratio of 5.4 in the solution, Ca ²⁺ / Cl ^1- = 0.4 and (Ca ²⁺ + Al ³⁺ ) / dinaphthalene sulfonate (CSN) = 1.9. The resulting mass is placed in molds in which hardening is carried out under the conditions: t = (8 ± 2) ^o C, relative humidity 95%. After 8 hours of hardening, part of the samples are redistributed and tested for compressive strength by a known method (GOST 310.4-85). The remaining samples harden within 24 hours, after which they undergo the procedure described above.

 Examples 2 to 9.

 They differ in the content of components and the composition of the target additive.

 The table presents examples of the compositions and properties of the proposed cement-injection material in comparison with the prototype.

Claims (1)

Grouting and injection material, including Portland cement and the target additive, characterized in that the latter contains an aqueous solution of Ca ²⁺ , Al ³⁺ and Cl ^1- ions, as well as dinaphthalene sulfonate (CSN) with Ca ²⁺ / Al ³⁺ = 5 - 6, Ca ²⁺ / Cl ^1- = 0.35 - 0.45 and Ca ²⁺ + Al ³⁺ / DNS = 1.3 - 2.4, the material additionally containing quartz sand in the following ratio of components, wt .%:
Portland cement - 40 - 43
Quartz sand - 40 - 43
Target supplement - 1.5 - 3.5
Water - Rest

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