Non-invasive repair and retrofitting of hardened reinforced concrete structures

Patent metadata

Field	Value
Publication number	US-10647616-B2
Application number	US-201615549789-A
Country	US
Kind code	B2
Filing date	Feb 9, 2016
Priority date	Feb 9, 2015
Publication date	May 12, 2020
Grant date	May 12, 2020

Abstract

Described is an aqueous composition for repairing and/or sealing of hardened concrete structures, the aqueous composition including colloidal silica and polycarboxylate ether. Also described is a method for repairing and/or sealing a hardened concrete structure, including a step of applying an aqueous composition including colloidal silica and polycarboxylate ether to a hardened concrete structure or a part thereof.

First claim

The invention claimed is:

1. A non-invasive method for repairing a hardened concrete structure, comprising:
applying an aqueous composition to the hardened concrete structure or a part thereof, the aqueous composition comprising colloidal silica and polycarboxylate ether,
wherein, based on a total weight of the aqueous composition, a content of the colloidal silica is in a range of 5 to 50% by weight and a content of the polycarboxylate ether is in a range of 2 to 50% by weight,
wherein a total amount of colloidal silica, polycarboxylate ether and water, based on the total weight of the aqueous composition, is at least 80% by weight,
wherein the aqueous composition does not contain cement, and
wherein the application of the aqueous composition to the hardened concrete structure is non-invasive.

2. The method according to claim 1 , wherein the weight average particle size of the colloidal silica is in the range of 1 nm to 150 nm.

3. The method according to claim 1 , wherein the weight average particle size of the colloidal silica is in the range of 5 nm to 10 nm.

4. The method according to claim 1 , wherein, based on the total weight of the aqueous composition the content of polycarboxylate ether is in the range of 2 to 25% by weight.

5. The method according to claim 1 , wherein the polycarboxylate ether is a comb polymer.

6. The method according to claim 1 , wherein the total amount of colloidal silica, polycarboxylate ether and water, based on the total weight of the aqueous composition, is at least 90% by weight.

7. The method according to claim 1 , wherein, based on the total weight of the aqueous composition, the content of water is at least 15% by weight.

8. The method according to claim 1 , wherein the hardened concrete structure is a hardened reinforced concrete structure.

9. The method according to claim 1 , wherein the aqueous composition is applied by injecting, migrating, infiltration or application onto the surface of the structure.

10. The method according to claim 1 , wherein the hardened concrete structure includes cracks.

11. The method according to claim 1 , wherein the method comprises at least one additional treatment of the concrete structure selected from protecting the reinforcement by application of a corrosion inhibiting agent, crack sealing with a reactive agent or waterproofing of the surface of the concrete structure with a hydrophobic material.

Assignees

• Sika Tech Ag

Inventors

• Valverde Cristina
• Granizo Fernandez Luz
• Garcia Ramiro

Classifications

• C04B2111/723

  Repairing reinforced concrete · CPC title

• C04B2111/00663

  as filling material for cavities or the like · CPC title

• B05D2203/30

  Other inorganic substrates, e.g. ceramics, silicon · CPC title

• C04B30/02

  containing fibrous materials · CPC title

• C04B41/5089

  Silica sols, alkyl, ammonium or alkali metal silicate cements · CPC title