High strength reduced elastic modulus concrete

Patent metadata

Field	Value
Publication number	US-11414348-B2
Application number	US-201715674645-A
Country	US
Kind code	B2
Filing date	Aug 11, 2017
Priority date	Aug 15, 2016
Publication date	Aug 16, 2022
Grant date	Aug 16, 2022

Abstract

Concrete that exhibits increased flexibility (i.e., low modulus of elasticity) and high compressive strength is described. High aspect ratio structures as may be formed of the concrete are described. Structures formed of the concrete can have the same high compressive strength as similar structures formed from a more conventional concrete but can be significantly more flexible, which can allow for better load distribution in the structure and associated assembly. The concrete includes a weathered granite as coarse aggregate. The materials can be particularly beneficial in forming concrete components of a rail infrastructure, such as railroad ties and slabs.

First claim

What is claimed is:

1. A structure having an aspect ratio of greater than 1, the structure comprising concrete having a compressive strength of 7 ksi or greater as determined according to ASTM C 39 (AASHTO T 22) and an elastic modulus of 4,300 ksi or less as determined according to ASTM C 469, the concrete comprising a coarse aggregate, the coarse aggregate comprising weathered granite aggregate having a cross sectional dimension of 0.19 inches or greater.

2. The structure of claim 1 , having an aspect ratio of 5 or greater.

3. The structure of claim 1 , wherein the structure is a rail infrastructure component.

4. The structure of claim 1 , wherein the structure is a railroad tie.

5. The structure of claim 1 , wherein the concrete of the structure is a high strength concrete or a high early strength concrete.

6. The structure of claim 1 , wherein the weathered granite aggregate has a cross sectional dimension of 0.4 inches to 1.5 inches.

7. The structure of claim 1 , the concrete having an elastic modulus of 2,600 ksi or less.

8. The structure of claim 1 , the concrete having a compressive strength of 8.5 ksi or greater and an elastic modulus of 2,900 ksi or less.

9. A method for forming the structure of claim 1 comprising forming the concrete according to a process that includes mixing water with dry materials to form a mixture, the dry materials including the coarse course aggregate, a fine aggregate, and a binder.

10. The method of claim 9 , the mixture including the water and the dry materials in a weight ratio of from 0.2 to 0.8.

11. The method of claim 9 , the mixture including the coarse aggregate in an amount of from 1700 pounds per cubic yard to 2000 pounds per cubic yard.

12. The method of claim 9 , the mixture including the fine aggregate in an amount of from 1120 pounds per cubic yard to 1200 pounds per cubic yard.

13. The method of claim 9 , the binder comprising two or more of a cement, fly ash, slag, and silica fume.

14. The method of claim 9 , the mixture including the binder in an amount of from 500 pounds per cubic yard to 1000 pounds per cubic yard.

15. The method of claim 9 , the binder comprising a Type III cement.

16. The method of claim 9 , wherein the mixing is carried out at a temperature up to 60° C.

Assignees

• Univ South Carolina

Inventors

• Rizos Dimitris

Classifications

• C04B28/02

  containing hydraulic cements other than calcium sulfates · CPC title

• C04B2111/0075

  for road construction · CPC title

• C04B14/048 Primary

  Granite · CPC title

• E01B3/28

  made from concrete or from natural or artificial stone (manufacture B28) · CPC title

• C04B28/08

  Slag cements · CPC title