Mitigation of alkali-silica reaction in concrete using readily-soluble chemical additives

Patent metadata

Field	Value
Publication number	US-11339094-B2
Application number	US-201816638720-A
Country	US
Kind code	B2
Filing date	Aug 13, 2018
Priority date	Aug 14, 2017
Publication date	May 24, 2022
Grant date	May 24, 2022

Abstract

A manufacturing method includes: (1) incorporating at least one soluble, calcium, magnesium, or other divalent cation-containing additive into a concrete mixture including aggregates prone to alkali-silica reaction; and (2) curing the concrete mixture to form a concrete product.

First claim

What is claimed is:

1. A manufacturing method, comprising:
subjecting aggregates to pre-treatment to form pre-treated aggregates;
incorporating the pre-treated aggregates into a concrete mixture; and
curing the concrete mixture to form a concrete product,
wherein subjecting the aggregates to pre-treatment includes exposing the aggregates to a solution including a divalent cation-containing additive.

2. The manufacturing method of claim 1 , wherein subjecting the aggregates to pre-treatment includes forming a divalent cation-containing interfacial barrier at least partially covering the aggregates.

3. The manufacturing method of claim 1 , wherein the aggregates include silica, and the divalent cation-containing additive suppresses alkali-silica reaction of the aggregates.

4. The manufacturing method of claim 1 , wherein the aggregates include at least one of (a) silicate glass or (b) strained or microcrystalline quartz.

5. The manufacturing method of claim 1 , further comprising identifying the aggregates as prone to alkali-silica reaction, and wherein subjecting the aggregates to pre-treatment is responsive to identifying the aggregates as prone to alkali-silica reaction.

6. The manufacturing method of claim 1 , wherein exposing the aggregates to a solution including a divalent cation-containing additive includes adjusting an amount of the divalent cation-containing additive according to at least one of an amount of the aggregates or a reactivity of the aggregates.

7. The manufacturing method of claim 1 , wherein the divalent cation-containing additive is a calcium-containing salt, a magnesium-containing salt, or the combination thereof.

8. The manufacturing method of claim 1 , wherein the divalent cation-containing additive is a calcium-containing salt.

9. The manufacturing method of claim 8 , wherein the calcium-containing salt is calcium chloride or calcium nitrite.

10. The manufacturing method of claim 9 , wherein the calcium-containing salt is calcium nitrate.

11. The manufacturing method of claim 1 , wherein the concrete mixture includes a cement, and the divalent cation-containing additive is incorporated into the concrete mixture in an amount of at least 1% by mass, relative to a mass of the cement included in the concrete mixture.

12. The manufacturing method of claim 1 , wherein the divalent cation-containing additive is incorporated into the concrete mixture in an amount sufficient to attain an initial concentration of the divalent cation ions in a pore solution of the concrete mixture of at least 30 mM.

13. The manufacturing method of claim 2 , wherein the divalent cation-containing interfacial barrier includes calcium-silicate-hydrate and calcite.

Assignees

• Univ California
• Yara Int Asa
• Construction Research & Technology Gmbh

Inventors

• Sant Gaurav N
• Falzone Gabriel D
• Oey Tandre
• Franke Wolfram
• Seiler Paul
• La Plante Erika Callagon

Classifications

• C04B14/06

  Quartz; Sand · CPC title

• C04B2103/603

  Agents for controlling alkali-aggregate reactions · CPC title

• C04B22/124

  Chlorides of ammonium or of the alkali or alkaline earth metals, e.g. calcium chloride · CPC title

• C04B28/02 Primary

  containing hydraulic cements other than calcium sulfates · CPC title

• C04B22/085 Primary

  containing nitrogen in the anion, e.g. nitrites · CPC title