Non-destructive evaluation of structural members
US5024091A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 12, 1989 |
| Grant date | Jun 18, 1991 |
| Priority date | — |
| Expiry date | Jun 12, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2203/0623
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Disclosed are testing apparatus and methods for estimating mechanical properties of nonhomogeneous materials, such as lumber and other wood materials and composite materials, particularly elongated slender members. The testing is appropriate for estimation of tensile and bending strength, tensile and bending moduli of elasticity and possibly other mechanical properties. The testing apparatus include a test specimen support which holds the specimen during testing in a manner which minimizes attenuation of the stress wave which is intentionally generated in the specimen to help predict the mechanical properties. The specimen supports also preferably include means for weighing the specimen which is combined with size information gathered through an optical scanning system thereby allowing the density to be obtained automatically. The specimens are impacted to produce a moving stress wave which is advantageously a longitudinal stress wave which moves longitudinally through the elongated slender members being reflected within the member preferably a number of times. The amplitude of the moving reflected stress wave is sensing with respect to time to allow the velocity and attenuation ra…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.