Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Stress wave based non-destructive evaluation techniques are frequently used for in-situ evaluation of concrete structures. Stress wave velocity in a material is related to Young Modulus of Elasticity. Thin circular disks sawn from cylinders or cores are widely used in measurement of rapid chloride permeability or air permeability of concrete and water soluble chloride penetration into concrete. While these methods provide useful information on concrete properties with depth, the capability of measuring changes in mechanical properties such as elastic modulus in small depth increments is of value to both researchers and consulting engineers conducting condition assessment when damage gradients exist. This study presents applications of Young modulus of thin disks to structural assessment projects involving damage and damage gradients. Non-destructive ultrasonic pulse velocity testing was used in identification of affected areas. Young modulus of thin concrete disks was used in validation of the NDE results and provided an improved understanding of the extent of damage that was indicated using NDE. Two different case studies are discussed: exposure to fire, and exposure to thermal shock and cryogenic temperatures. The use of thin disks enabled determination of mechanical properties of relatively thin layers of concrete and, therefore, provided a means to quantitatively assess the extent of damage gradients. Validation of NDE results using modulus data and analytical modeling using the relationship between Young modulus and pulse velocity provided improved understanding of NDE findings reducing uncertainty in engineering analysis and improving repair recommendations.
Stress wave based non-destructive evaluation techniques are frequently used for in-situ evaluation of concrete structures. Stress wave velocity in a material is related to Young Modulus of Elasticity. Thin circular disks sawn from cylinders or cores are widely used in measurement of rapid chloride permeability or air permeability of concrete and water soluble chloride penetration into concrete. While these methods provide useful information on concrete properties with depth, the capability of measuring changes in mechanical properties such as elastic modulus in small depth increments is of value to both researchers and consulting engineers conducting condition assessment when damage gradients exist. This study presents applications of Young modulus of thin disks to structural assessment projects involving damage and damage gradients. Non-destructive ultrasonic pulse velocity testing was used in identification of affected areas. Young modulus of thin concrete disks was used in validation of the NDE results and provided an improved understanding of the extent of damage that was indicated using NDE. Two different case studies are discussed: exposure to fire, and exposure to thermal shock and cryogenic temperatures. The use of thin disks enabled determination of mechanical properties of relatively thin layers of concrete and, therefore, provided a means to quantitatively assess the extent of damage gradients. Validation of NDE results using modulus data and analytical modeling using the relationship between Young modulus and pulse velocity provided improved understanding of NDE findings reducing uncertainty in engineering analysis and improving repair recommendations.
Dynamic elastic Young's modulus of concrete disks in validation of stress wave based non-destructive testing technique results
Dynamischer Elastizitätsmodul von Betonscheiben mittels Validierung von Spannungswellen basierten zerstörungsfreien Prüfergebnissen
Dilek, U. (Autor:in)
2006
23 Seiten, 8 Bilder, 2 Tabellen, 15 Quellen
Aufsatz (Konferenz)
Datenträger
Englisch
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