Structural concrete mix for construction for electromagnetic wave/pulse shielding

Patent metadata

Field	Value
Publication number	US-2016234977-A1
Application number	US-201414392258-A
Country	US
Kind code	A1
Filing date	Jun 24, 2014
Priority date	May 16, 2011
Publication date	Aug 11, 2016
Grant date	—

Abstract

Conductive concrete mixtures are described that are configured to provide EMP shielding and reflect and/or absorb, for instance, EM waves propagating through the conductive concrete mixture. The conductive concrete mixtures include cement, water, conductive carbon material, magnetic material, and metallic conductive material. The conductive carbon material may include conductive carbon particles, conductive carbon powder, and/or coke breeze. The metallic conductive material may include steel fibers, and the magnetic material may include taconite. The conductive concrete mixture may also include supplementary cementitious materials (SCM). A method of making a concrete structure includes pouring a concrete mixture to form conductive concrete, and positioning a first conductive screen within the conductive concrete proximate to an exterior surface of the conductive concrete. The method also includes positioning a second conductive screen within the conductive concrete in electrical contact with the first conductive screen.

First claim

What is claimed is:

1 . A concrete structure, comprising:
conductive concrete formed from a concrete mixture comprising
cement,
water,
conductive carbon material comprising from at least approximately one percent (1%) to at least approximately twenty percent (20%) of the concrete mixture by weight,
magnetic material comprising from at least approximately twenty percent (20%) to at least approximately fifty percent (50%) of the concrete mixture by weight, and
metallic conductive material;
a first conductive screen disposed within the conductive concrete and positioned proximate to an exterior surface of the conductive concrete; and a second conductive screen disposed within the conductive concrete and in electrical contact with the first conductive screen.

2 . The concrete structure as recited in claim 1 , wherein the first conductive screen is positioned less than at least approximately three inches (3 in.) from the exterior surface of the conductive concrete.

3 . The concrete structure as recited in claim 1 , wherein the second conductive screen is positioned proximate to a second exterior surface of the conductive concrete, the second exterior surface of the conductive concrete generally opposite the exterior surface of the conductive concrete.

4 . The concrete structure as recited in claim 1 , wherein at least one of the first conductive screen or the second conductive screen comprises a woven wire mesh defining a plurality of apertures each having a characteristic opening size of less than at least approximately two-tenths of an inch (0.2 in.).

5 . The concrete structure as recited in claim 1 , wherein at least one of the first conductive screen or the second conductive screen comprises a mesh having a first plurality of elongated wires arranged proximate to one another across a second plurality of elongated wires, the first plurality of elongated wires and the second plurality of elongated wires directly fastened together to define a plurality of apertures each having a characteristic opening size of less than at least approximately three inches (3 in.).

6 . The concrete structure as recited in claim 1 , further comprising a third conductive screen disposed within the conductive concrete between the first conductive screen and the second conductive screen, the third conductive screen in electrical contact with the first conductive screen and the second conductive screen.

7 . The concrete structure as recited in claim 1 , wherein the metallic conductive material comprises at least one of steel fibers, steel wool, or steel powder.

8 . The concrete structure as recited in claim 1 , wherein the magnetic material comprises at least one of taconite, magnetite, kamacite, taenite, titanohematite, pyrrhotite, ilmenite, or titanomagnetite.

9 . The concrete structure as recited in claim 1 , wherein the conductive carbon material comprises at least one of carbon particles, conductive carbon powder, or coke breeze.

10 . The concrete structure as recited in claim 1 , wherein the metallic conductive material comprises from at least approximately one percent (1%) to at least approximately fifteen percent (15%) of the concrete mixture by weight.

11 . A method of making a concrete structure, comprising:
blending conductive carbon material and magnetic material to a form a dry mix; adding cement and water to the dry mix to form a wet mix; adding metallic conductive material to the wet mix; mixing the metallic conductive material and the wet mix to form a concrete mixture; pouring the concrete mixture to form conductive concrete; positioning a first conductive screen within the conductive concrete proximate to an exterior surface of the conductive concrete; and positioning a second conductive screen within the conductive concrete in electrical contact with the first conductive screen.

12 . The method as recited in claim 11 , wherein the first conductive screen is positioned less than at least approximately three inches (3 in.) from the exterior surface of the conductive concrete.

13 . The method as recited in claim 11 , wherein the second conductive screen is positioned proximate to a second exterior surface of the conductive concrete, the second exterior surface of the conductive concrete generally opposite the exterior surface of the conductive concrete.

14 . The method as recited in claim 11 , wherein at least one of the first conductive screen or the second conductive screen comprises a woven wire mesh defining a plurality of apertures each having a characteristic opening size of less than at least approximately two-tenths of an inch (0.2 in.).

15 . The method as recited in claim 11 , wherein at least one of the first conductive screen or the second conductive screen comprises a mesh having a first plurality of elongated wires arranged proximate to one another across a second plurality of elongated wires, the first plurality of elongated wires and the second plurality of elongated wires directly fastened together to define a plurality of apertures each having a characteristic opening size of less than at least approximately three inches (3 in.).

16 . The method as recited in claim 11 , further comprising positioning a third conductive screen within the conductive concrete between the first conductive screen and the second conductive screen, the third conductive screen in electrical contact with the first conductive screen and the second conductive screen.

17 . The method as recited in claim 11 , wherein the metallic conductive material comprises at least one of steel fibers, steel wool, or steel powder.

18 . The method as recited in claim 11 , wherein the magnetic material comprises at least one of taconite, magnetite, kamacite, taenite, titanohematite, pyrrhotite, ilmenite, or titanomagnetite.

19 . The method as recited in claim 11 , wherein blending conductive carbon material and magnetic material to form a dry mix further comprises blending conductive carbon particles, conductive carbon powder, crushed taconite aggregate, and supplementary cementitious material (SCM) to form a dry mix.

20 . The method as recited in claim 11 , wherein the conductive carbon material comprises from at least approximately one percent (1%) to at least approximately twenty percent (20%) of the concrete mixture by weight, and the magnetic material comprises from at least approximately twenty percent (20%) to at least approximately fifty percent (50%) of the concrete mixture by weight.

21 . A method of making a concrete structure, comprising:
pouring a concrete mixture to form conductive concrete; positioning a first conductive screen within the conductive concrete proximate to an exterior surface of the conductive concrete; and positioning a second conductive screen within the conductive concrete in electrical contact with the first conductive screen.

22 . The method as recited in claim 21 , wherein the first conductive screen is positioned less than at least approximately three inches (3 in.) from the exterior surface of the conductive concrete.

23 . The concrete structure as recited in claim 21 , wherein the second conductive screen is positioned proximate to a second exterior surface of the conductive concrete, the second exterior surface of the conductive concrete generally opposite the exterior surface of the conductive concrete.

24 . The concrete structure as recited in claim 21 , wherein at least one

Assignees

• Univ Nebraska

Inventors

• Tuan Christopher
• Nguyen Lim

Classifications

• C04B2111/00258

  Electromagnetic wave absorbing or shielding materials · CPC title

• C04B28/04

  Portland cements · CPC title

• E04B1/92

  Protection against other undesired influences or dangers (buildings providing protection against external dangers E04H9/00; shielding against dangerous radiation G21F) · CPC title

• H05K9/0003 Primary

  Shielded walls, floors, ceilings, e.g. wallpaper, wall panel, electro-conductive plaster, concrete, cement, mortar · CPC title

• B28B23/02

  wherein the elements are reinforcing members {(B28B23/0006 takes precedence)} · CPC title