Controllable high flow concrete

Patent metadata

Field	Value
Publication number	US-11352301-B2
Application number	US-201716341752-A
Country	US
Kind code	B2
Filing date	Oct 11, 2017
Priority date	Oct 14, 2016
Publication date	Jun 7, 2022
Grant date	Jun 7, 2022

Abstract

The present invention relates to very high workable yet controllable concrete mix design, admixture composition, and process for placing concrete. The mix design relates to particular aggregate/cement ratios and types which are characteristic of ready mix concrete (RMC), which provide high fluidity reminiscent of self-consolidating concrete (SCC), and which provides advantages over both RMC and SCC in terms of ease and speed in placement and finishability at the construction site placement zone, regardless of whether into a horizontal formwork (e.g., for slabs, floors) or into vertical formwork (e.g., for blocks, walls, columns, etc.), without loss of control and without generating high risks of segregation even when small amounts of water are added at the size to facilitate finishing of the concrete surface. An inventive admixture combination which enables this unique design involves two different polycarboxylate comb polymers in combination with two specific viscosity modifying agents, and this combination provides highly workable concrete to be placed in a controlled, efficient manner.

First claim

It is claimed:

1. A process for placing a high flow concrete into a placement zone, comprising:
(A) providing, at a delivery site, at least one concrete delivery mixer-truck load of concrete having a total pour volume of 1 to 16 cubic yards into a placement zone, the concrete load mixture comprising (i) coarse aggregate in the amount of at least 1550 pounds per cubic yard based on total volume of the concrete load mixture, wherein at least thirty percent of the coarse aggregate is retained on a sieve with a 0.5 inch opening as determined by standard sieve testing under ASTM C33/C33M-16; (ii) cementitious binder in the amount of 376-752 pounds per cubic yard of the concrete load mixture; (iii) a polysaccharide biopolymer selected from the group consisting of welan, diutan, xanthan, guar gum, or mixture thereof, the biopolymer being present in the amount of 0.0003 to 0.003 per hundred pounds of cementitious binder within the concrete load mixture; (iv) a modified cellulose present in the amount of 0.0005 to 0.005 per hundred pounds of cementitious binder within the concrete load mixture; and (v) at least two cement dispersant polycarboxylate comb polymers having pendant (poly)alkylene oxide groups selected from ethylene oxide, propylene oxide, or mixture thereof, said at least two comb polymers each being present in the amount of 0.02 to 0.12 pounds per 100 pounds of cementitious binder in the concrete load mixture, a first of said at least two comb polymers having zero to less than six percent mole fraction hydrolysable groups selected from esters, amides, or mixture thereof, a second of said at least two comb polymers having six percent or higher mole fraction of hydrolysable groups selected from esters, amides, or mixture thereof, and said second comb polymer having at least two percent more hydrolysable groups than said first comb polymer; and
(B) pouring, into a placement zone to form a pavement, slab, floor, elevated deck, foundation, bridge deck, wall, column, dam, or portion thereof, the concrete load mixture having a slump flow within the range of 13 to 30 inches.

2. The process of claim 1 wherein the placement zone has a volume which exceeds the delivery truck-load pour volume.

3. The process of claim 1 wherein the concrete load mixture comprises a fine aggregate selected from natural sand, manufactured (crushed) sand, or mixture thereof.

4. The process of claim 3 wherein the fine aggregate comprises at least 50% manufactured (crushed) sand based on weight of total fine aggregates in the concrete load mixture.

5. The process of claim 1 wherein the at least two cement dispersant comb polymers are both obtained from three monomer Components A, B, and C, wherein Component A is an unsaturated carboxylic acid monomer represented by structural formula 1,

component B is a polyoxyalkylene monomer represented by structural formula 2:

and
component C is an unsaturated carboxylate ester or amide monomer represented by structural formula 3:

wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , and R 10 each individually represent a hydrogen atom, a C1 to C4 alkyl group, or —COOM group wherein M represents a hydrogen atom or an alkali metal; Y represents -(CH 2 ) p - wherein “p” represents an integer of 0 to 6; Z represents —O—, —COO—, —OCO—, —COHN—, or —NHCO— group; -(AO)n represents repeating ethylene oxide groups, propylene oxide groups, butylene oxide groups, or a mixture thereof; “n” represents the average number of repeating -(AO)- groups and is an integer of from 10 to 250; W represents an oxygen atom or an —NH— group, and R 11 represents a C 1 -C 10 alkyl group or a C 2 -C 10 hydroxyalkyl group.

6. The process of claim 5 wherein the first of said at least two comb polymers provides slump enhancement in the concrete load mixture and has components A and B in a molar ratio (A:B+C) in the range of 2:1 to 5:1, and comprises component C in an amount of 0 to less than 0.2 [mole fraction of repeat units]; and wherein the second of said at least two comb polymer enhances slump retention in the concrete load mixture and has components A, B, and C in the molar ratio range (A:B+C) of 0.3:1 to 3:1, wherein component C is present in an amount of at least 0.2 [mole fraction of repeat units]; and further wherein the first polymer and second polymer are present in the ratio of 9:1 to 1:9.

7. The process of claim 6 wherein the concrete mix load comprises at least three different cement dispersant polycarboxylate comb polymers.

8. The process of claim 6 wherein one comb polymer is used having six percent or higher mole fraction of hydrolysable groups selected from esters, amides, or mixture thereof, and two comb polymers having at least two percent more fewer hydrolysable groups than said first comb polymer.

9. The process of claim 1 wherein the concrete mix load wherein the biopolymer is diutan and the modified cellulose is hydroxypropylmethylcellulose.

10. The process of claim 1 wherein the modified cellulose is selected from the group consisting of hydroxyethylmethylcellulose, hydroxypropylmethylcellulose, or mixture thereof.

11. The process of claim 1 wherein the concrete mix load further comprises at least one additional chemical admixture component selected from the group consisting of a set retarder, a set accelerator, an air detraining agent, an air entraining agent, a finishing or pumping aid, shrinkage reducing admixture, expanding agents, fibers, corrosion inhibitor, pigments, a clay mitigating agent or a mixture thereof.

12. The process of claim 1 wherein the concrete load mixture is poured having a slump flow within 16 to 24 inches.

13. The process of claim 1 wherein the placement zone is prepared for concrete flatwork as defined by ACI CT-16, whereby the pouring provides a concrete pavement, slab-on-grade, mat foundation, floor, bridge deck, or portion thereof.

14. The process of claim 13 wherein the concrete being poured into an area prepared for concrete flatwork as defined by ACI CT-16, having a slump flow radius, R, as a result of performing a slump flow test in accordance to ASTM C1611/C1611M-14, and a maximum height, H, of the concrete mass as a result of performing a slump flow test in accordance to ASTM C1611/C1611M-14, has an H value

1
≤

π
⁢

⁢

R
2

⁢
H

V

≤
2.5

,

that satisfies: where V is the volume of the slump cone.

15. The process of claim 14 wherein the concrete being poured into an area having concrete flatwork as defined by ACI CT-16, the concrete having a leading edge has a curvature compared to an uppermost area of the concrete poured when subjected to slump flow test in accordance to ASTM C1611/C1611M-14, wherein the height as a function of the radial spread, h(r), evaluated where the first de

Assignees

• Gcp Applied Tech Inc

Inventors

• Burns Elizabeth
• Tregger Nathan A
• Koyata Hideo
• Kuo Lawrence L
• Rieder Klaus-Alexander
• Roberts Mark F
• Myers David

Classifications

• Y02W30/91

  Use of waste materials as fillers for mortars or concrete · CPC title

• C04B14/06

  Quartz; Sand · CPC title

• C04B2201/10

  for the viscosity · CPC title

• C04B40/0039 Primary

  Premixtures of ingredients · CPC title

• C04B24/32

  Polyethers, e.g. alkylphenol polyglycolether · CPC title