Electromagnetic analysis of concrete tensioning wires
US6781369B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 11, 2003 |
| Grant date | Aug 24, 2004 |
| Priority date | — |
| Expiry date | Mar 19, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N33/383
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Discloses methods to perform magnetic testing of tensioning elements in a pre-stressed concrete cylinder, such as a pipe or water reservoir and testing apparatus. The apparatus includes magnetic flux production means and detector means disposed proximal to a surface of the cylinder in a plane in common with the magnetic flux production means that is orthogonal to an axis of the cylinder. The apparatus operates over a range of low frequency signals, for example, between 20 and 300 hertz or a pulse. Output of the inspection apparatus includes a signal and distance plot showing the results of testing a cylinder at one or more frequencies. In accordance with another method of analysis, a characteristic of the phase of the output over distance is plotted, including the phase or representations of the in-phase or quadrature components of the received signal in relation to the driving signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.