Systems and methods utilizing carbon nanofiber aggregate for performance monitoring of concrete structures
AssigneeUniversity of Houston
InventorsYi-Lung Mo, Rachel Howser, Hermant Dhonde, Gangbing Song
Life of this patent
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Abstract
A carbon nanofiber aggregate (CNFA) system and method provides self-sensing capabilities that can be used to detect strain, moisture, and temperature changes. The CNFA may include cement, aggregate, silica fume, high-range water reducer (HRWR), and/or carbon nanofibers. The metal meshes in the CNFA may be utilized to monitor the electric properties of the CNFA to detect strain, moisture, and temperature changes. The CNFA may be embedded in concrete structures to allow detection of strain, moisture, and temperature changes that may cause damage to structures. Several metal meshes may be embedded in the CNFA.
Claims22
A system for monitoring a structure comprising:
- a carbon nanofiber aggregate (CNFA) formed from a mixture of cement, aggregate, high-range-water reducer, and carbon nanofibers (CNF);
- a plurality of metallic meshes positioned in the CNFA, wherein each of the plurality of metallic meshes are positioned parallel to each other;
- and
- a wire coupled to each of the plurality of metallic meshes.
A method for monitoring a structure comprising:
- positioning a carbon nanofiber aggregate (CNFA) in a concrete structure, wherein the CNFA comprises
- a mixture of cement, aggregate, high-range-water reducer, and carbon nanofibers (CNF);
- a first pair of metallic meshes positioned in the CNFA, wherein the first pair of metallic meshes are positioned parallel to each other;
- a second pair of metallic meshes positioned in the CNFA, wherein the second pair of metallic meshes are positioned parallel to each other;
- a wire coupled to each of the first pair of metallic meshes and the second pair of metallic meshes;
- applying a current to the first pair of metallic meshes;
- monitoring a voltage change between the second pair of metallic meshes;
- and
- determining a resistance based on the voltage change between the second pair of metallic meshes.
A method for forming a carbon nanofiber aggregate (CNFA) comprising:
- blending a first mixture of water, a High Range Water Reducer (HRWR), and carbon nanofibers (CNF);
- blending a second mixture of cement and aggregate;
- combining and blending a first portion of the first mixture with the second mixture;
- combining and blending a second portion of the first mixture with the second mixture;
- combining and blending a third portion of the first mixture with the second mixture form a final mixture;
- positioning a plurality of metallic meshes in a formwork, wherein each of the plurality of metallic meshes is coupled to a wire, and the plurality of metallic meshes are secured in position by holes provided by the formwork;
- pouring the final mixture into the formwork, wherein the final mixture surrounds the plurality of metallic meshes, and the wires coupled to the plurality of metallic meshes extend out of the final mixture;
- and
- curing the final mixture.
Dependencies are inferred from the claim text.