Mitigation of corrosion in carbonated concrete based on low-calcium silicate cement

Patent metadata

Field	Value
Publication number	US-12012365-B2
Application number	US-201916283460-A
Country	US
Kind code	B2
Filing date	Feb 22, 2019
Priority date	Feb 22, 2018
Publication date	Jun 18, 2024
Grant date	Jun 18, 2024

Abstract

The invention provides methods and compositions that prevent, mitigate or delay the onset of corrosion of iron or steel (e.g., plain carbon steel) components used as reinforcement or otherwise at least partially embedded in carbonated concrete composite materials and objects based on carbonatable calcium silicate cement.

First claim

We claim:

1. A carbonated composite material, comprising
a bonding matrix comprising a plurality of bonding elements; and
a plurality of pores comprising a pore solution having a pH greater than about 9.5,
wherein each bonding element comprises
a core, wherein the core comprises of a carbonatable material,
a first silica-rich layer that at least partially covers some peripheral portion of the core, and
a second calcium and/or magnesium carbonate-rich layer that at least partially covers some peripheral portion of the first silica-rich layer; and
wherein the carbonated composite material has a compressive strength of 3,500 psi or greater.

2. The carbonated composite material of claim 1 , wherein the pore solution has a pH of about 10 to about 13.5.

3. The carbonated composite material of claim 2 , wherein the carbonated composite material has a compressive strength of 4,000 psi or greater.

4. The carbonated composite material of claim 2 , wherein the carbonated composite material has a compressive strength of 5,000 psi or greater.

5. The carbonated composite material of claim 1 , wherein the material has a compressive strength greater than about 7,000 psi.

6. The carbonated composite material of claim 4 , wherein the material has a compressive strength greater than about 10,000 psi.

7. The carbonated composite material of claim 1 , wherein the bonding matrix further comprises one or more pH enhancing additives.

8. The carbonated composite material of claim 7 , wherein the one or more pH enhancing additives is selected from the group consisting of calcium nitrate tetrahydrate, calcium nitrite, NaOH, sodium bicarbonate, OPC, sodium silicate, high alkalinity concrete recycled material, slag aggregate, deadburned CaO, deadburned MgO, and combinations thereof.

9. The carbonated composite material of claim 1 , wherein the porous body further comprises one or more additives to improve water resistance.

10. The carbonated composite material of claim 9 , wherein the one or more additives to improve water resistance is selected from the group consisting of Class C fly ash, Class F fly ash, ground granulated blast furnace slag (GGBFS), fine glass powder, vitreous calcium aluminosilicate, silica fume, limestone powder, and combination thereof.

11. The carbonated composite material of claim 1 , wherein the porous body further comprises one or more water reducing additives, air entraining additives, set retarders, and combinations thereof.

12. A concrete object comprising the carbonated composite material of claim 1 further comprising one or more iron or steel components at least partially embedded therein.

13. The concrete object of claim 12 , wherein the one or more iron or steel components is made of plain carbon steel, epoxy coated steel, galvanized steel, and/or stainless steel.

14. The concrete object of claim 12 , wherein the one or more iron or steel components is a reinforcement bar or mesh.

15. The carbonated composite material of claim 1 , wherein the pore solution has a pH greater than about 10.

16. The carbonated composite material of claim 1 , wherein the compressive strength is greater than about 7,000 psi.

Assignees

• Solidia Technologies Inc
• Solidia Tech Ltd

Inventors

• Jain Jitendra
• Seth Anuj
• Atakan Vahit
• Tas Ahmet Cuneyt
• Sahu Sadanada

Classifications

• C04B40/0231

  Carbon dioxide hardening · CPC title

• C04B28/188 Primary

  the Ca-silicates being present in the starting mixture · CPC title

• Y02W30/91

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

• Y02P40/18

  Carbon capture and storage [CCS] · CPC title

• C04B14/34

  Metals {, e.g. ferro-silicon} · CPC title