CN1257126C

CN1257126C - Concrete sweller

Info

Publication number: CN1257126C
Application number: CN 200410024350
Authority: CN
Inventors: 季元升
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-06-15
Filing date: 2004-06-15
Publication date: 2006-05-24
Anticipated expiration: 2024-06-15
Also published as: CN1583645A

Abstract

The present invention discloses a concrete expansion agent which comprises the following components of the proportion by weight: 20 to 55% of aluminium ore, 20 to 60% of gypsum, 5 to 20% of lime, 0 to 35% of fly ashes and 0 to 1% of saccharic calcium. The components are put into a ball mill and then milled so as to obtain the expansion agent. By using the technical scheme, general alunite used commonly is replaced by the aluminium ore in a formula. The concrete expansion agent produced by the technical scheme of the present invention is a subalkaline concrete expansion agent which hardly contains K2O and Na2O because the aluminium ore does not contain the K2O and the Na2O. Accordingly, the alkali-aggregate reaction can not occur after the concrete expansion agent is used for preparing concrete, and concrete structures can not be damaged. The present invention has the advantages of high property, less addition amount and good practical application value.

Description

A kind of cement expansive material

Technical field

The present invention relates to a kind of cement expansive material, be characterized in a kind of little alkali cement expansive material.

Background technology

Cement expansive material is widely used in vault, people's air defense, tunnel, retention basin and concrete for hydraulic structure engineering, and cement expansive material is the focus that people pay close attention to the influence of concrete durability.Alkali content is too high in the concrete, easily causes alkali-aggregate reaction, causes structure deteriorate, is one of major reason that influences concrete durability, and the alkali content in the concrete derives from gelling material and admixture.Abroad the alkali content to cement all has regulation, less than 0.6% be low alkali cement, being higher than more than 0.8～1.0% is high-alkali cement.Beijing takes the lead in proposing being brought into by admixture that alkali content is controlled at 1kg/m in the concrete in nineteen ninety-five ³Below.Alunite is one of common used material of concrete batching swelling agent, and the swelling agent product of China uses this material mostly at present, contains K in the alunite ₂O and Na ₂O (is converted to Na ₂The O meter) being 2～4%, be raw-material swelling agent alkalinity height with alunite therefore, and the volume in concrete is bigger, and more than 11% of water in soil mud amount is coagulated in general blending.

Summary of the invention

The object of the present invention is to provide a kind of difficult initiation alkali-aggregate reaction, better performances, cement expansive material that volume is little.

For achieving the above object, the technical solution of the utility model is: a kind of cement expansive material comprises following component: aluminum ore, gypsum, lime, flyash, sugared calcium.The weight percent of described component is: aluminum ore 20～55%, and gypsum 20～60%, lime 5～20%, flyash 14.2～35%, sugared calcium 0.5～1% is put into ball mill with described component, makes behind grinding.

Owing to adopted technique scheme, with not containing K ₂O and Na ₂The aluminum ore of O replaces containing K ₂O and Na ₂The alunite of O is so contain K hardly in the cement expansive material that adopts technical solution of the present invention to make ₂O and Na ₂The O composition, so alkali-aggregate reaction can not take place, the destruction that also can not cause concrete structure, and the cement expansive material that adopts technical solution of the present invention to make mixes in the concrete, the oxyhydroxide that has volume to increase in early days generates, and the basicity of raising liquid phase, make the ettringite crystal of generation more tiny, having gelatinous hydrated product to generate does not simultaneously fill, can produce bigger expansion character, make and expand and the intensity coordinated development, and the product that behind grinding, makes with present technique, intensity is better with other performance.If levigate to specific surface area greater than 500m ²/ kg can be used as microdilatancy ultrafine powder preparation high-strength high-performance concrete, can significantly improve the performance of concrete mix and maturing, especially can improve concrete weather resistance (comprising the performance that reduces concrete shrinkage).

Embodiment

Embodiment one, and a kind of cement expansive material comprises following component: aluminum ore, gypsum, lime, flyash, sugared calcium.The weight percent of described component is: aluminum ore 30%, and gypsum 40%, lime 10%, flyash 19.5%, sugared calcium 0.5% is put into ball mill with described component, makes behind grinding.

Embodiment two, and a kind of cement expansive material comprises following component: aluminum ore, gypsum, lime, flyash, sugared calcium.The weight percent of described component is: aluminum ore 40%, and gypsum 30%, lime 15%, flyash 14.2%, sugared calcium 0.8% is put into ball mill with described component, makes behind grinding.

Compare as follows according to above-mentioned test-results:

Mix 6～8% cement expansive materials that adopt technical solution of the present invention to make in the concrete cement, the rate of expansion that increases glue sand along with volume increases, and during volume 6%, seven days rate of expansion is 0.032%, and during volume 8%, seven days rate of expansion are just greater than 0.04%; Mixed 6～8% o'clock, 28 days rate of expansion is less than 0.1% of regulation; Water is supported maintenance 21 days in air in seven days, and rate of expansion also is not less than-0.02% of regulation; As shown in the table, swelling agent replaces with DBC in the table.

Numbering	Agglutination material (%)		Standard sand (g)	W/C	Maintenance limited expansion rate (%) in the water				Water was supported after 7 days in the air maintenance 21 days
	Agglutination material (%)				Maintenance limited expansion rate (%) in the water					Cement	DBC	3 days	7 days	14 days	28 days
	1	100				1350	0.40	0.0045		Cement	DBC	3 days	7 days	14 days	28 days	0.0057	0.0071	0.0078	-0.0272
2	1	100	90	10		1350	0.40	0.0045	1350	0.40	0.040	0.055	0.064	0.071	0.014	0.0057	0.0071	0.0078	-0.0272
2	3	92	90	10	8	1350	0.40	0.038	1350	0.40	0.040	0.055	0.064	0.071	0.014	0.045	0.048	0.054	0.002
4	3	92	94	6	8	1350	0.40	0.038	1350	0.40	0.028	0.032	0.036	0.040	-0.010	0.045	0.048	0.054	0.002

This shows that the glue sand expansion character of mixing 6～8% swelling agent reaches the requirement of JC476-1998.

According to the test of the test method in the Technical code for application of admixture in concrete (GBJ119-88), proportioning is 1: 1.73: 2.82, the results are shown in following table,

Numbering	Agglutination material (%)		W/C	The slump (mm)	Ultimate compression strength (MPa)				Maintenance limited expansion rate (* 10 in the water ^-4)
	Agglutination material (%)				Ultimate compression strength (MPa)				Maintenance limited expansion rate (* 10 in the water ^-4)				Cement	DBC	3 days	7 days	28 days	60 days	3 days	7 days	14 days	28 days
	1	100				0.462	40	26.8	45.8	51.8	59.1	0.14	Cement	DBC	3 days	7 days	28 days	60 days	3 days	7 days	14 days	28 days	0.16	0.20	0.20
2	1	100	88	12		0.462	40	26.8	45.8	51.8	59.1	0.14	0.446	50	21.8	35.8	50.0	56.7	2.11	3.21	4.09	4.46	0.16	0.20	0.20
2	3	90	88	12	10	0.446	60	22.9	40.2	52.6	63.2	1.96	0.446	50	21.8	35.8	50.0	56.7	2.11	3.21	4.09	4.46	3.12	3.58	3.61
4	3	90	92	8	10	0.446	60	22.9	40.2	52.6	63.2	1.96	0.446	45	24.4	45.2	52.4	62.6	1.8	2.02	2.31	2.41	3.12	3.58	3.61
4	5	94	92	8	6	0.446	45	25.9	47.5	54.2	61.0	1.49	0.446	45	24.4	45.2	52.4	62.6	1.8	2.02	2.31	2.41	1.62	1.87	1.97

As seen from the above table, when mixing 6～8% swelling agent, 14 days limited expansion rate of concrete is 1.87～2.31 * 10 ^-4Meet the requirement of Technical code for application of admixture in concrete fully, regulation is greater than 1.5 * 10 ^-4

According to the strength property of test method test glue sand among the JC476-1998, glue sand 1: 2.5 the results are shown in following table

Numbering	Agglutination material (%)		Standard sand (g)	W/C	Folding strength (MPa)		Ultimate compression strength (MPa)
	Agglutination material (%)				Folding strength (MPa)		Ultimate compression strength (MPa)		Cement	DBC	7 days	28 days	7 days	28 days
	1	100				1350	0.44	7.10	Cement	DBC	7 days	28 days	7 days	28 days	8.55	43.4	52.9
2	1	100	90	10		1350	0.44	7.10	1350	0.44	6.51	8.35	40.3	53.1	8.55	43.4	52.9
2	3	92	90	10	8	1350	0.44	6.79	1350	0.44	6.51	8.35	40.3	53.1	8.42	43.0	55.7
4	3	92	94	6	8	1350	0.44	6.79	1350	0.44	7.17	8.50	45.2	56.5	8.42	43.0	55.7

As seen from the above table, cement mortar strength has all reached the requirement among the JC476-1998, the 28 day length of time folding strength and benchmark glue sand close, but ultimate compression strength all slightly improves.

Claims

1, a kind of cement expansive material is characterized in that: comprise following component, aluminum ore, gypsum, lime, flyash, sugared calcium; The weight percent of described component is: aluminum ore 20～55%, gypsum 20～60%, lime 5～20%, flyash 14.2～35%, sugared calcium 0.5～1%; Described component is put into ball mill, behind grinding, make.