Method of reinforcing irregular structures

Patent metadata

Field	Value
Publication number	US-9278889-B2
Application number	US-201113696705-A
Country	US
Kind code	B2
Filing date	May 10, 2011
Priority date	May 12, 2010
Publication date	Mar 8, 2016
Grant date	Mar 8, 2016

Abstract

The present disclosure provides a method for reinforcing irregular rock or irregular concrete surfaces such as rock structures in mines as well as other rock and concrete structures. The method includes applying a curable foam composition to at least a portion of a surface, at least partially curing the curable foam composition to form a foam layer adhered to the surface, applying a curable reinforcing composition onto at least a portion of the foam layer, and at least partially curing the curable reinforcing composition to form a reinforcing layer, wherein at least a portion of the reinforcing layer is adhered to the foam layer.

First claim

What is claimed is:

1. A method for providing a reinforcing coating on an irregular rock or concrete surface, the method comprising:
a) applying a curable foam composition onto at least a portion of a surface, wherein the surface is selected from a group consisting of an irregular rock surface and an irregular concrete surface and combinations thereof, and wherein the curable foam composition comprises a mixture of a foam composition polyisocyanate component and a foam composition polyol component;
b) at least partially curing the curable foam composition to form a polyurethane foam layer, wherein at least a portion of the foam layer is adhered to the surface;
c) applying a curable reinforcing composition onto at least a portion of the foam layer, wherein the curable reinforcing composition comprises a reinforcing composition polyisocyanate component and a reinforcing composition polyamine component, wherein the reinforcing composition polyisocyanate component has an isocyanate number in a range from 27% to 32%, the curable reinforcing composition further comprising at least one of a flow agent or a de-aeration agent;
d) at least partially curing the curable reinforcing composition to form a polyurea reinforcing layer, wherein at least a portion of the reinforcing layer is adhered to the foam layer, thereby forming the reinforcing coating on the surface.

2. The method of claim 1 , wherein the surface is a portion of a mine.

3. The method of claim 2 wherein the portion of the mine is selected from the group consisting of a wall, a back, a face, and combinations thereof.

4. The method of claim 1 wherein the applying in steps (a) and (c) comprises spraying.

5. The method of claim 1 wherein the curable foam composition further comprises water in an amount of 0.5% by wt. to 5% by wt.

6. The method of claim 1 wherein step (a) comprises heating at least a portion of the curable foam composition to a temperature in the range of from about 50° C. to about 70° C.

7. The method of claim 1 wherein the curing in step b comprises an exothermic reaction of the curable foam composition.

8. The method of claim 7 wherein the foam layer has an integral skin.

9. The method of claim 1 wherein the reinforcing layer has a tensile strength value as measured according to ASTM D412-06ae2 of at least 20 MPa.

10. The method of claim 1 wherein the reinforcing layer has a percent elongation value as measured according to ASTM D412-06ae2 of at least 200 percent.

11. The method of claim 1 wherein the reinforcing layer has a tear resistance value as measured according to ASTM D624-00(2007) of at least 122 kilonewtons per meter.

12. A surface of a mine coated using the method of claim 1 .

13. A composite comprising:
a surface of a mine; and
a reinforcing coating disposed on at least a portion of the surface of the mine, the reinforcing coating comprising:
a foam layer adhered to at least a portion of the surface of the mine, wherein the foam layer comprises a polyurethane; and
a reinforcing layer adhered to at least a portion of the foam layer, wherein the reinforcing layer comprises a polyurea, wherein the polyurea is formed from a curable reinforcing composition comprising a reinforcing composition polyisocyanate component and a reinforcing composition polyamine component, wherein the reinforcing composition polyisocyanate component has an isocyanate number in a range from 27% to 32%, the curable reinforcing composition further comprising at least one of a flow agent or a de-aeration agent;
wherein the surface of the mine is a portion of the mine selected from a group consisting of a wall, a floor, a back, and combinations thereof.

14. The composite of claim 13 , wherein the foam layer has a density in the range of from about 40 kg/m 3 to about 144 kg/m 3 .

15. The composite of claim 13 wherein the reinforcing layer has a tensile strength value as measured according to ASTM D412-06ae2 of at least 20 MPa.

16. The composite of claim 13 wherein the reinforcing layer has a percent elongation value as measured according to ASTM D412-06ae2 of at least 200 percent.

17. The composite of claim 13 wherein the reinforcing layer has a tear resistance value as measured according to ASTM D624-00(2007) of at least 122 kilonewtons per meter.

Assignees

• Rayner Terrence John
• Hastings David John
• Livingstone David Edward
• 3M Innovative Properties Co

Inventors

• Rayner Terrence John
• Hastings David John
• Livingstone David Edward

Classifications

• C04B28/02

  containing hydraulic cements other than calcium sulfates · CPC title

• C04B2111/00724

  in mining operations, e.g. for backfilling; in making tunnels or galleries · CPC title

• C04B14/00

  Use of inorganic materials as fillers, e.g. pigments, for mortars, concrete or artificial stone; Treatment of inorganic materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone (expanding or defibrillating materials C04B20/00) · CPC title

• C04B41/52

  Multiple coating or impregnating {multiple coating or impregnating with the same composition or with compositions only differing in the concentration of the constituents, is classified as single coating or impregnation} · CPC title

• C04B41/488

  Other macromolecular compounds obtained otherwise than by reactions only involving unsaturated carbon-to-carbon bonds · CPC title