Grout composition

• US 5,454,866 A
• Filed: 02/07/1995
• Issued: 10/03/1995
• Est. Priority Date: 06/23/1992
• Status: Expired due to Fees

• Current Assignee: H L & H Timber Products
• Original Assignee: H L & H Timber Products
• Inventors: Howell, Mark, Gilbert, Gregory M., Kirsten, Paul S., McConnachie, Terrence M.
• Primary Examiner(s): GREEN, ANTHONY J
• Application Number:
  US08/385,196
• Time in Patent Office: 238 Days
• Field of Search: 106/695, 106/735, 106/775, 405/288, 405/289
• US Class Current: 106/695
• CPC Class Codes: C04B 11/05 obtaining anhydrite, e.g. Keene's cementC04B11/028 takes precedence
• CPC Class Codes: C04B 2103/00 Function or property of ingredients for mortars, concrete or artificial stone
• CPC Class Codes: C04B 2103/0008 Li
• CPC Class Codes: C04B 2103/0067 the ingredients being formed in situ by chemical reactions or conversion of one or more of the compounds of the composition
• CPC Class Codes: C04B 2111/00724 in mining operations, e.g. for backfilling; in making tunnels or galleries
• CPC Class Codes: C04B 2111/70 Grouts, e.g. injection mixtures for cables for prestressed concrete
• CPC Class Codes: C04B 22/0093 Aluminates
• CPC Class Codes: C04B 22/06 Oxides, Hydroxides C04B22/0013 takes precedence
• CPC Class Codes: C04B 22/062 of the alkali or alkaline-earth metals
• CPC Class Codes: C04B 22/08 Acids or salts thereof C04B22/0013 takes precedence
• CPC Class Codes: C04B 22/10 containing carbon in the anion
• CPC Class Codes: C04B 22/143 Calcium-sulfate
• CPC Class Codes: C04B 24/18 Lignin sulfonic acid or derivatives thereof, e.g. sulfite lye
• CPC Class Codes: C04B 28/06 Aluminous cements monolithic refractories or refractory mortars C04B35/66
• CPC Class Codes: C04B 7/02 Portland cement
• CPC Class Codes: E21D 15/483 made of flexible containers, e.g. inflatable, with or without reinforcement, e.g. filled with water, backfilling material or the like laggings making use of fluid cushions E21D11/157

Abstract

This invention relates to a grout composition comprising a Portland cement, a high alumina cement, anhydrous calcium sulphate, an effective amount of a lithium salt and an effective amount of a strong base. According to another aspect of the invention, instead of using a strong base directly in the grout composition, a first compound and a second compound is added to the grout composition which in use react to form an effective amount of a strong base when the grout composition is mixed with water.

Claims

1. A grout composition which sets after being mixed with water comprising:

a Portland cement wherein the Portland cement comprises between 20 and 80% by weight of the total grout composition;

a high alumina cement wherein the high alumina cement comprises between 17 and 35% by weight of the total grout composition;

anhydrous calcium sulphate wherein the anhydrous calcium sulphate comprises between 20 and 40% by weight of the total grout composition;

an effective amount of a lithium salt to provide accelerated setting of the high alumina cement; and

an effective amount of a strong base to provide accelerated setting of the Portland cement, the strong base selected from the group consisting of sodium hydroxide, potassium hydroxide and sodium aluminate.

3. A grout composition according to claim 1 or claim 2 which further comprises an effective amount of a retarding agent to provide a retarding effect on the setting of the grout composition.

4. A grout composition according to claim 1 or claim 2 wherein the Portland cement is ordinary Portland cement.

5. A grout composition according to claim 1 or claim 2 wherein the Portland cement is rapid hardening Portland cement.

6. A grout composition according to claim 1 or claim 2 wherein the anhydrous calcium sulphate is α

-anhydrite or β

-anhydrite or a mixture thereof.

7. A grout composition according to claim 1 or claim 2 wherein the lithium salt is selected from the group consisting of lithium carbonate and lithium hydroxide.

8. A grout composition according to claim 1 or claim 2 wherein the strong base is sodium hydroxide.

9. A grout composition according to claim 1 or claim 2 wherein the Portland cement comprises between 30 and 55% by weight of the total grout composition.

10. A grout composition according to claim 1 or claim 2 wherein the high alumina cement comprises between 20 and 28% by weight of the total grout composition.

11. A grout composition according to claim 1 or claim 2 wherein the anhydrous calcium sulphate comprises between 25 and 32% by weight of the total grout composition.

12. A grout composition according to claim 1 or claim 2 wherein the lithium salt comprises between 0.05 and 1% by weight of the high alumina cement.

13. A grout composition according to claim 1 or claim 2 wherein the lithium salt comprises between 0.07 and 0.7% by weight of the high alumina cement.

14. A grout composition according to claim 1 or claim 2 wherein the strong base comprises between 0.3 and 3% by weight of the Portland cement.

15. A grout composition according to claim 1 or claim 2 wherein the strong base comprises between 0.5 and 1.5% by weight of the Portland cement.

16. A grout composition according to claim 1 or claim 2 and which further comprises a retarding agent, wherein the retarding agent is selected from the group consisting of a lignosulphonate and a salt of a lignosulphonate.

17. A grout composition according to claim 1 or claim 2 and which further comprises a retarding agent, wherein the retarding agent is selected from the group consisting of sodium lignosulphonate, calcium lignosulphonate, magnesium lignosulphonate and ferrochrome lignosulphonate.

18. A grout composition according to claim 1 or claim 2 and which further comprises a retarding agent to provide a retarding effect on the setting of the grout composition, wherein the retarding agent comprises between 0.006 and 1.7% by weight of the total grout composition.

19. A grout composition according to claim 1 or claim 2 and which further comprises a retarding agent to provide a retarding effect on the setting of the grout composition, wherein the retarding agent comprises between 0.5 and 0.8% by weight of the total grout composition.

23. A wet grout composition comprising:

a grout composition according to claim 1 or claim 2; and

water.

24. A wet grout composition comprising:

a grout composition according to claim 1 or claim 2; and

water, wherein the weight ratio of water to grout composition is between 0.5;

1 and 4.0;

1.

25. A pack setting bag having a grout composition according to claim 1 or claim 2 located therein.

26. A method of supporting a hanging wall above a footwall in a mine including the steps of:

(a) providing a support on the footwall;

(b) providing a pack setting bag between the support and the hanging wall;

(c) locating a wet grout composition comprising a mixture of a grout composition according to claim 1 or claim 2 and water, inside the pack setting bag; and

(d) allowing the wet grout composition to set.

2. A group composition which sets after being mixed with water comprising:

a Portland cement wherein the Portland cement comprises between 20 and 80% by weight of the total group composition;

a high alumina cement wherein the high alumina cement comprises between 17 and 35% by weight of the total grout composition;

anhydrous calcium sulphate wherein the anhydrous calcium sulphate comprises between 20 and 40% by weight of the total grout composition;

an effective amount of a lithium salt to provide accelerated setting of the high alumina cement; and

a first compound and a second compound which in use react to form an effective amount of a strong base when the grout composition is mixed with water so as to provide accelerated setting of the Portland cement, the formed strong base selected from the group consisting of sodium hydroxide, potassium hydroxide and sodium aluminate.

20. A grout composition according to claim 2 wherein the first compound is selected from the group comprising a carbonate salt of an alkali metal compound, a carbonate salt of an alkali earth metal compound, a nitrate salt of an alkali metal compound and a nitrate salt of an alkali earth metal compound or a combination thereof, and the second compound is selected from the group comprising calcium oxide and calcium hydroxide or a combination thereof.

21. A grout composition according to claim 2 wherein the first compound is selected from the group consisting of Li₂ CO₃, Na₂ CO₃, K₂ CO₃, LiHCO₃, NaHCO₃, KHCO₃, NaNO₃, KNO₃, LiNO₃, Ca(NO₃)₂ or a combination thereof, and the second compound is selected from the group comprising calcium oxide and calcium hydroxide or a combination thereof.

22. A grout composition according to claim 2 wherein the first compound is sodium carbonate and the second compound is calcium hydroxide which in use react to form sodium hydroxide when the grout composition is mixed with water.