Method and apparatus for accelerated corrosion testing

Patent metadata

Field	Value
Publication number	US-11867609-B2
Application number	US-201917265106-A
Country	US
Kind code	B2
Filing date	Jun 28, 2019
Priority date	Aug 6, 2018
Publication date	Jan 9, 2024
Grant date	Jan 9, 2024

Abstract

An accelerated corrosion test apparatus includes: a moisture sensor disposed near the reinforcing steel exposed from a cracked portion of concrete; a weight measuring instrument that measures a weight of the reinforced concrete specimen; and a control terminal that is connected both to the moisture sensor and to the weight measuring instrument and controls a temperature and humidity control device, thereby alternately and repeatedly performing a wetting step of supplying moisture to the inside of a crack in the cracked concrete, and a drying step of removing moisture in the inside of the crack and moisture on the exposed surface of the reinforcing steel, wherein the control terminal terminates the wetting step and starts the drying step when moisture is detected in the moisture sensor, or when change in slope of weight change of the reinforced concrete specimen is detected, after the start of the wetting step.

First claim

The invention claimed is:

1. An accelerated corrosion test method wherein corrosion of a reinforcing steel contained in a reinforced concrete specimen having a crack with an inside that extends to the reinforcing steel so as to expose a surface of the reinforcing steel is accelerated, wherein
a control terminal is connected both to a moisture sensor contained within the reinforced concrete specimen, and to a weight measuring instrument that measures a weight of the reinforced concrete specimen, and controls a moisture supply and removal device, thereby alternately and repeatedly performing:
a wetting step of supplying a moisture to the inside of the crack in the reinforced concrete specimen so that the moisture extends to the exposed surface of the reinforcing steel; and
a drying step of terminating the wetting step and removing the moisture in the inside of the crack and the moisture on the exposed surface of the reinforcing steel when the moisture is detected in the moisture sensor, or when change in slope of weight change of the reinforced concrete specimen is detected, after the start of the wetting step.

2. The accelerated corrosion test method according to claim 1 , wherein the control terminal terminates the drying step and starts the wetting step when moisture is no longer detected in the moisture sensor, or when the weight of the reinforced concrete specimen is decreased by an amount corresponding to the increment in weight when the change in slope of weight change has been detected, after the start of the drying step.

3. The accelerated corrosion test method according to claim 2 , wherein in the wetting step, the reinforced concrete specimen is immersed in water, or moisture is sprayed to the reinforced concrete specimen.

4. The accelerated corrosion test method according to claim 1 , wherein the control terminal regards an increased weight of the reinforced concrete specimen as a moisture content in the inside of the crack, and terminates the wetting step when change in slope of change in the moisture content in the inside of the crack is detected instead of the detection of the change in slope of weight change of the reinforced concrete specimen, or when the moisture content in the inside of the crack reaches a saturated moisture content based on an internal volume of the crack.

5. The accelerated corrosion test method according to claim 4 , wherein the control terminal terminates the drying step when the moisture content in the inside of the crack is decreased by an amount corresponding to the saturated moisture content.

6. The accelerated corrosion test method according to claim 5 , wherein in the wetting step, the reinforced concrete specimen is immersed in water, or moisture is sprayed to the reinforced concrete specimen.

7. The accelerated corrosion test method according to claim 4 , wherein in the wetting step, the reinforced concrete specimen is immersed in water, or moisture is sprayed to the reinforced concrete specimen.

8. The accelerated corrosion test method according to claim 1 , wherein in the wetting step, the reinforced concrete specimen is immersed in water, or moisture is sprayed to the reinforced concrete specimen.

9. An accelerated corrosion test apparatus that accelerates corrosion of a reinforcing steel contained in a reinforced concrete specimen having a crack with an inside that extends to the reinforcing steel so as to expose a surface of the reinforcing steel, comprising:
a moisture sensor disposed within the reinforced concrete specimen;
a weight measuring instrument that measures a weight of the reinforced concrete specimen; and
a control terminal that is connected both to the moisture sensor and to the weight measuring instrument and controls a moisture supply and removal device, the control terminal being configured to alternately and repeatedly perform a wetting step of supplying a moisture to the inside of the crack in the reinforced concrete specimen so that the moisture extends to the exposed surface of the reinforcing steel, and a drying step of removing the moisture in the inside of the crack and the moisture on the exposed surface of the reinforcing steel, wherein
the control terminal terminates the wetting step and starts the drying step when the moisture is detected in the moisture sensor, or when change in slope of weight change of the reinforced concrete specimen is detected, after the start of the wetting step.

10. The accelerated corrosion test apparatus according to claim 9 , wherein
the control terminal terminates the drying step and starts the wetting step when moisture is no longer detected in the moisture sensor, or when the weight of the reinforced concrete specimen is decreased by an amount corresponding to the increment in weight when the change in slope of weight change has been detected, after the start of the drying step.

11. The accelerated corrosion test apparatus according to claim 9 , wherein
the control terminal regards an increased weight of the reinforced concrete specimen as a moisture content in the inside of the crack, and terminates the wetting step and starts the drying step when change in slope of change in the moisture content in the inside of the crack is detected instead of the detection of the change in slope of weight change of the reinforced concrete specimen, or when the moisture content in the inside of the crack reaches a saturated moisture content based on an internal volume of the crack, and terminates the drying step and starts the wetting step when the moisture content in the inside of the crack is decreased by an amount corresponding to the saturated moisture content.

Assignees

• Nippon Telegraph & Telephone

Inventors

• Takeuchi Yosuke
• Miwa Takashi
• Kamisho Takuya
• Oka Soichi

Classifications

• G01N17/006 Primary

  of metals · CPC title

• G01N33/2045

  Defects · CPC title

• G01N17/002 Primary

  Test chambers · CPC title

• G01N33/383

  Concrete or cement · CPC title