Concrete composition

Patent metadata

Field	Value
Publication number	US-2018290926-A1
Application number	US-201615573999-A
Country	US
Kind code	A1
Filing date	May 12, 2016
Priority date	May 15, 2015
Publication date	Oct 11, 2018
Grant date	—

Abstract

A concrete composition having, in a mixture with water, a hydraulic binder, sand, aggregates, an expanding agent and a shrinkage reducing admixture, wherein the expanding agent is calcium oxide having a low reactivity such that the concrete casted using the composition does not expand by more than 0.05 vol. % during the first 10 days, preferably not expanding more than 0.05 vol. % during the first 7 days, after having been cast.

First claim

1 . A concrete composition that is
(a) a concrete composition comprising, in a mixture with water, a hydraulic binder, sand, aggregates, an expanding agent and a shrinkage reducing admixture, wherein the expanding agent is calcium oxide having a low reactivity such that the concrete does not expand by more than 0.05 vol. %-0.05 vol. %, during the first 10 days, after having been casted; or (b) a concrete composition comprising, in a mixture with water, a hydraulic binder, sand, aggregates, an expanding agent and a shrinkage reducing admixture, wherein the expanding agent is calcium oxide having a low reactivity such that the concrete does not expand by more than 0.05 vol. %, during the first 7 days, after having been casted.

2 . The concrete composition according to claim 1 , wherein the calcium oxide has a particle size distribution characterized by a residue of at least 6 wt. on a 45 μm mesh sieve.

3 . The concrete composition according to claim 1 , wherein the calcium oxide has a reactivity that is characterized by a conductivity of <11 mS/cm when dissolved in water.

4 . The concrete composition according to claim 1 , wherein the calcium oxide has a reactivity that is characterized by an average temperature increase of <0.5° C./min during the first 15 minutes after the addition of the calcium oxide into water.

5 . The concrete composition according to claim 1 , wherein the calcium oxide has a reactivity that is characterized by a temperature increase of <10° C. during the first 5 minutes after the addition of the calcium oxide into water.

6 . The concrete composition according to claim 1 , wherein the hydraulic binder comprises ordinary Portland cement and optionally supplementary cementitious material.

7 . The concrete composition according to claim 1 , wherein the shrinkage reducing admixture is an organic admixture.

8 . The concrete composition according to claim 1 , wherein the mixture further comprises a water reducing agent in an amount of 20-60 ml/100 kg hydraulic binder.

9 . The concrete composition according to claim 1 , wherein the volume change of the concrete is between +0.01 and −0.01 vol. % after 365 days after having been casted.

10 . The concrete composition according to claim 1 , wherein the concrete composition is formulated with amounts of expanding agent and shrinkage reducing admixture so that the volume change of the concrete is between +0.010 and −0.01 vol. % after 365 days after having been casted.

11 . The concrete composition according to claim 1 , wherein the concrete composition contains the expanding agent in an amount of 2-6 wt. % of the hydraulic binder.

12 . The concrete composition according to claim 1 , wherein the concrete composition contains the shrinkage reducing admixture in an amount of 1-2 wt. % of the hydraulic binder.

13 . The concrete composition according to claim 1 , wherein the concrete composition has a water/binder ratio is 0.15-0.50.

14 . The concrete composition according to claim 1 , wherein the hydraulic binder is present in an amount of 280-700 kg per cubic meter of concrete.

15 . A hydraulic binder composition for producing a very low-shrinkage concrete, comprising ordinary Portland cement, optionally a supplementary cementitious material and an expanding agent, wherein the expanding agent is calcium oxide,
the calcium oxide has a particle size distribution characterized by a residue of at least 6 wt. % on a 45 μm mesh sieve, and/or the calcium oxide has a reactivity that is characterized by a conductivity of <11 mS/cm when dissolved in water, and/or the calcium oxide has a reactivity that is characterized by an average temperature increase of <0.5° C./min during the first 15 minutes after the addition of the calcium oxide into water, and/or the calcium oxide has a reactivity that is characterized by a temperature increase of <10° C. during the first 5 minutes after the addition of the calcium oxide into water.

16 . The hydraulic binder according to claim 15 , further comprising a shrinkage reducing admixture in powder form.

17 - 22 . (canceled)

23 . A construction element comprising concrete concrete produced obtained from a concrete composition according to claim 1 .

24 . The concrete composition according to claim 1 , wherein when the concrete composition is (a) the expanding agent is calcium oxide having a low reactivity such that the concrete does not expand by more than 0.03 vol. % during the first 10 days; or when the concrete composition is (b) the expanding agent is calcium oxide having a low reactivity such that the concrete does not expand by more than 0.03 vol. % during the first 7 days.

25 . The concrete composition according to claim 6 , wherein the optionally supplementary cementitious material comprises granulated blast furnace slag, fly ash, pozzolans or mixtures thereof.

27 . The concrete composition according to claim 7 , wherein the shrinkage reducing admixture is an organic admixture-based on polypropylene glycol, polyethylene glycol and/or a glycol ether derivative, optionally in a liquid mixture with surfactants.

Assignees

• Holcim Technology Ltd

Inventors

• Baalbaki Moussa
• Gong Bill
• Babayan David
• Matthes Winnie

Classifications

• C04B2111/346

  Materials exhibiting reduced plastic shrinkage cracking · CPC title

• C04B14/06

  Quartz; Sand · CPC title

• C04B28/04 Primary

  Portland cements · CPC title

• C04B24/32

  Polyethers, e.g. alkylphenol polyglycolether · CPC title

• C04B22/064

  of the alkaline-earth metals · CPC title