FORMULATION, UTILISATION AND PROCESS TO OBTAIN A LIGHTWEIGHT STRUCTURAL CONCRETE

• US 20100212551A1
• Filed: 10/10/2008
• Published: 08/26/2010
• Est. Priority Date: 10/12/2007
• Status: Active Grant

• Current Assignee: Holcim Technology, Ltd. (Holcim Limited)
• Original Assignee: Lafarge SA (Holcim Limited)
• Inventors: Bonnet, Emmanuel, Schwartzentruber, Arnaud, Meille, Sylvain, Chanvillard, Gilles
• Granted Patent: US 8,394,192 B2
• Time in Patent Office: Days
• US Class Current: 106/708
• CPC Class Codes: C04B 14/12 Expanded clay
• CPC Class Codes: C04B 14/28 of calcium
• CPC Class Codes: C04B 18/08 Flue dust , i.e. fly ash
• CPC Class Codes: C04B 18/141 Slags
• CPC Class Codes: C04B 18/146 Silica fume
• CPC Class Codes: C04B 2103/304 Air-entrainers
• CPC Class Codes: C04B 2103/32 Superplasticisers
• CPC Class Codes: C04B 2111/00198 Characterisation or quantities of the compositions or their ingredients expressed as mathematical formulae or equations
• CPC Class Codes: C04B 2111/40 Porous or lightweight materials
• CPC Class Codes: C04B 24/2647 containing polyether side chains
• CPC Class Codes: C04B 28/02 containing hydraulic cements other than calcium sulfates
• CPC Class Codes: Y02W 30/91 Use of waste materials as fillers for mortars or concrete

Abstract

A lightweight structural concrete includes a hydraulic binder; effective water; a superplasticizer; and aggregates; the concrete having a density in the fresh state varying from 1.40 to a D_max value calculated according to formula (I) D_max=1.58+(a×AM) in which “a” represents a coefficient for which the value is equal to 1; “AM” represents the mass percentage of the amorphous materials contained in 1 m³ of fresh concrete; the concrete having a maximum fresh state density D_max less than or equal to 1.85; the concrete having a W_effective/L ratio varying from 0.19 to 0.46, where W_effective represents the quantity of effective water in kilogram per cubic metre of fresh concrete; “L” represents the quantity of cement and additions in kilograms per cubic metre of fresh concrete; the concrete including a quantity of effective water varying from 100 to 230 litres per cubic metre of fresh concrete; the concrete including a quantity of Portland clinker greater than or equal to 150 kilograms per cubic metre of fresh concrete; the concrete including a quantity of (Portland clinker+optionally fly ash+optionally slags+optionally silica fume+optionally calcined shale+optionally calcined clays) greater than or equal to 300 kilograms per cubic metre of fresh concrete; the concrete having a volume of paste greater than or equal to 300 l/m³ of fresh concrete; the concrete including from 1 to 16% by volume of air.

Claims

1. A lightweight structural concrete comprising:

a hydraulic binder;

effective water;

a superplasticizer; and

aggregates;

said concrete having a density in the fresh state varying from 1.40 to a D_max value calculated according to formula (I)

D_max=1.58+(a×

AM) 

 

Formula (I)

in which “

a”

represents a coefficient for which the value is equal to 1

“

AM”

represents the mass percentage of the amorphous materials contained in 1 m³ of fresh concrete;

said concrete having a maximum fresh state density D_max less than or equal to 1.85,

said concrete having a W_effective/L ratio varying from 0.19 to 0.46,

where W_effective represents the quantity of effective water in kilogram per cubic metre of fresh concrete;

“

L”

represents the quantity of cement and additions in kilograms per cubic metre of fresh concrete;

said concrete comprising a quantity of effective water varying from 100 to 230 litres per cubic metre of fresh concrete;

said concrete comprising a quantity of Portland clinker greater than or equal to 150 kilograms per cubic metre of fresh concrete;

said concrete comprising a quantity of (Portland clinker+optionally fly ash+optionally slags+optionally silica fume+optionally calcined shale+optionally calcined clays) greater than or equal to 300 kilograms per cubic metre of fresh concrete;

said concrete having a volume of paste greater than or equal to 300 l/m³ of fresh concrete;

said concrete comprising from 1 to 16% by volume of air.

3. The concrete according to claim 1 comprising at least one treated aggregate which has been sprayed with a material.

4. The concrete according to claim 1, comprising a hydraulic binder selected from a cement of type:

CEM III, CEM IV or CEM V, or

CEM I or CEM II, mixed with additions.

5. The concrete according to claim 1, comprising a cement of the CEM I or CEM II type, mixed with additions of the slag, or fly ash, or silica fume types or any combination thereof.

6. The concrete according to claim 1, wherein the proportion of air in the mix varies from 1% to 16% by volume, from 2% to 8% by volume.

7. The concrete according to claim 1, wherein the proportion of air is less than 5% by volume.

8. The concrete according to claim 1, comprising a superplasticizer such as a polycarboxylate polyoxide.

9. A process for the preparation of a lightweight structural concrete according to claim 1, the process comprising a mixture of at least:

a hydraulic binder;

effective water;

a superplasticizer; and

aggregates;

the said concrete having a W_effective/L ratio varying from 0.19 to 0.46,

where W_effective represents the quantity of effective water in kilogram per cubic metre of fresh concrete;

“

L”

represents the quantity of cement and additions in kilograms per cubic metre of fresh concrete;

said concrete comprising a quantity of effective water varying from 100 to 230 litres per cubic metre of fresh concrete;

said concrete comprising a quantity of Portland clinker greater than or equal to 150 kilograms per cubic metre of fresh concrete;

concrete comprising a quantity of (Portland clinker+optionally fly ash+optionally slags+optionally silica fume+optionally calcined shale+optionally calcined clays) greater than or equal to 300 kilograms per cubic metre of fresh concrete;

said concrete having a volume of paste greater than or equal to 300 l/m³ of fresh concrete;

said concrete comprising from 1 to 16% by volume of air.

10. Use of a lightweight structural concrete according to claim 1 as a construction material.

11. A hardened concrete object obtained from a lightweight structural concrete according to claim 1.

12. The concrete according to claim 1, wherein “

a”

is equal to 0.9.

13. The concrete according to claim 1, wherein “

a”

is equal to 0.8.

14. The concrete according to claim 1, wherein the maximum fresh state density D_max is less than or equal to 1.8.

15. The concrete according to claim 14, wherein the maximum fresh state density D_max is less than or equal to 1.7.

2. (canceled)