Claims
- 1. A method for producing a sand-lime building brick of low bulk density comprising the steps of:
- (a) preparing a mixture of sand, lime, water and cement, said mixture consisting essentially of sand, lime and water and also including a relatively small amount of cement as a binder, said cement being present in relatively small amount in relation to the total amount of said sand, lime and water, said cement being present in an amount in excess of 1% by weight to provide said mixture with a green strength of at least 1 kg/cm.sup.2 subsequent to compaction of said mixture;
- (b) compacting said mixture in a mold at a pressure of less than 150 kg/cm.sup.2 to form green brick;
- (c) removing said green brick from said mold;
- (d) transporting said green brick to an autoclave; and
- (e) curing said green brick in the autoclave to form said building brick.
- 2. The method of claim 1, in which the compacting step is carried out by means of vibrating said mixture within said mold.
- 3. The method of claim 1, in which the mixture is left to stand for up to one hour following addition of the cement to initiate strength-forming reactions before the mixture is compacted.
- 4. The method of claim 1, in which the cement is a quick-setting cement.
- 5. The method of claim 4, in which the quick-setting cement is added to the mixture in an amount ranging from at least about 1% to about 6% by weight of cement based on the weight of the mixture.
- 6. The method of claim 1, in which the sand is at least partially replaced by light-weight aggregates.
- 7. The method of claim 1, in which foam-forming agents are added to the mixture prior to compaction.
- 8. The method of claim 1, in which the sand has a particle size of less than 0.25 mm.
- 9. The method of claim 1, in which the bricks have a porosity of at least 25%.
- 10. The method of claim 1, in which the mixture comprises 10% by weight CaO, 5% by weight of water in addition to the necessary water for slaking, 81% by weight of sand with a particle size of up to 2 mm and 4% by weight of quick-setting cement and in which the mixture is left to stand for about 1/2 hour and then compacted at a pressure of 10 kp/cm.sup.2.
- 11. The method of claim 1, in which stabilizers are added to the mixture to prevent decomposition.
- 12. In a method for producing a sand-lime building brick by molding a mixture consisting essentially of sand, lime, and water in a mold under pressure to form green brick, removing the green brick from the mold and curing the green brick in an autoclave to produce said building brick, the improvements of: lowering the bulk density of the building brick by incorporating in said mixture a relatively small amount of cement as a binder, said amount being small in relation to the total amount of said sand, lime and water, and compacting said mixture at a pressure less than 150 kg/cm.sup.2 to form the green brick, said cement being present in said mixture in an amount sufficient to produce a green brick having a strength of at least 1 kg/cm.sup.2.
- 13. The method of claim 12, in which said compacting step is carried out by vibrating said mixture within said mold.
- 14. The method of claim 12, in which the cement is a quick-setting cement.
- 15. The method of claim 12, in which the bricks have a porosity of at least 25%.
Parent Case Info
This is a continuation of application Ser. No. 692,747, filed June 4, 1976, now abandoned.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
3226242 |
Huettemann |
Dec 1965 |
|
3438853 |
Haines et al. |
Apr 1969 |
|
3764357 |
Bowles et al. |
Oct 1973 |
|
Continuations (1)
|
Number |
Date |
Country |
Parent |
692747 |
Jun 1976 |
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