CN1237549A

CN1237549A - Composite cement

Info

Publication number: CN1237549A
Application number: CN99109932A
Authority: CN
Inventors: 孟云芳
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-06-25
Filing date: 1999-06-25
Publication date: 1999-12-08
Anticipated expiration: 2019-06-25
Also published as: CN1110460C

Abstract

The present invention relates to a composite cement made up by using (wt%) 23%-45% of cement clinker, 4-5% of gypsum, 42-66.5% of mixture material formed from slag and pulverized fuel ash and 6-10% of calcium hydroxide and sodium carbonate mixture throug a certain mixing process. Said invention can effectively raise the early-strength and after-strength of the composite cement, improve the toughness and brittleness of cement, raise the crack resistance of concrete and greatly reduce the production cost of the cement.

Description

Complex cement

The present invention relates to a kind of complex cement, particularly a kind of admixture has a large amount of flyash and scoriaceous cement.

Flyash is a large amount of refuses of discharging of modern industry boiler, and its harm to environment is well-known, and people make a large amount of effort in the hope of it is turned waste into wealth as the gelling material in the cement for this reason, and one can reduce environmental pollution; Two can reduce cement cost, as Chinese patent CN1063856A, a kind of rehydration mud and adulterating agent thereof were just once disclosed, in this complex cement admixture a large amount of flyash, made good try, but it is poor that this invention does not solve toughness that cement had and fragility that the prior art that comprises Portland cement produces, thereby make poor, the easy fissured difficult problem of crack-resistant performance of concrete, and can this invention do not add the later strength that improve cement yet and indicate.

The objective of the invention is to overcome above-mentioned shortcoming, provide a kind of new admixture coal ash in a large number and in early days, later stage strength of cement and bending and compressive strength be improved, cement toughness and fragility are significantly improved, thereby also can effectively improve the NEW TYPE OF COMPOSITE cement of crack-resistant performance of concrete.

The solution of the present invention is such:

A kind of complex cement, formulated by cement clinker, gypsum mixture and exciting agent, wherein compound is made by slag and flyash, and exciting agent is by calcium hydroxide [Ca (OH) ₂] and yellow soda ash (NaCO ₃) make.

The proportion relation of complex cement is as follows:

1. No. 525 Portland clinker 23-45%

2. compound is 42-66.5%

Wherein: slag is the 40-60% of compound gross weight

Flyash is the 60-40% of compound gross weight

The cement that the present invention produced, not only flyash mixed dosage is big, and early stage, the later strength of cement all be higher than the complex cement with label, and can improve the toughness of cement, reduces its fragility, thereby improves concrete resistance to cleavage, reduces the crack.

Test case is as follows:

1. hydration heat is low, and 7 days thermal value is respectively 219.9 and 205KJ/KG, and 230KJ/KG is low than the low-heat slag cement.

2. intensity index (F represents slag in the table, and S represents flyash) as shown in the table:

28 days intensity indexs

Numbering	Grog (%)	Mixing material volume (F+s)		Exciting agent (%)	Folding strength (MPa)			Ultimate compression strength (MPa)
					Folding strength (MPa)			Ultimate compression strength (MPa)			3 days	7 days	28 days	3 days	7 days	28 days
					????1	?25	?????????66.5％		????8	????6.5	3 days	7 days	28 days	3 days	7 days	28 days	????7.6	??9.3	??26.3	??33.2	??50.1
???F60％	S40％						?????????66.5％
???F60％	S40％	????2	?35	?????????60％			????8	????6.9			????8.8	??10.0	??32.4	??38.1	??55.2
???F40％	S60％			?????????60％
???F40％	S60％			????3	?45	?????????50％			????8	????5.1						????6.8	??9.5	??28.8	??38.8	??52.2
???F60％	S40％					?????????50％

Embodiment 1: with accounting for No. 525 Portland clinkers of gross weight 25%, by be mixed 66.5% compound of general cement production process, 5% gypsum and 8% exciting agent can be produced complex cement No. 325.

Embodiment 2: with No. 525 Portland clinkers that account for gross weight 35%, the compound of admixture 60%, 5% gypsum and 8% exciting agent can be used for producing complex cement No. 425.

Embodiment 3: with No. 525 Portland clinkers that account for gross weight 45%, 50% compound, 5% gypsum and 8% exciting agent can be produced complex cement No. 525.

Claims

1. complex cement by cement clinker, gypsum, compound and exciting agent preparation, is characterized in that compound made by slag and flyash, and the exciting agent major ingredient is calcium hydroxide [Ca (OH) ₂] and yellow soda ash (NaCO ₃).

2. complex cement according to claim 1 is characterized in that the prescription of complex cement is:

1. No. 525 Portland clinker 23-45%

2. compound is 42-66.5

Wherein: slag is the 40-60% of compound gross weight

Flyash is the 60-40% of compound gross weight

3. gypsum 4-5%

4. exciting agent 6-10%

Wherein: calcium hydroxide [Ca (OH) ₂] be 60%, yellow soda ash (NaCO ₃) be 40%

3. complex cement according to claim 2 is characterized in that: account for No. 525 Portland clinkers of gross weight 25%, admixture compound 66.5%; Gypsum 5%, exciting agent 8% is used to produce complex cement No. 325.

4. complex cement according to claim 2 is characterized in that accounting for No. 525 Portland clinkers of gross weight 35%, and the compound of admixture 60%, 5% gypsum and 8% exciting agent are used to produce complex cement No. 425.

5. complex cement according to claim 2 is characterized in that compound, 5% gypsum and 8% the exciting agent of No. 525 Portland clinker admixtures 50% of gross weight 45% being used to produce complex cement No. 525.