Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Infrared thermography assessment of masonry arch bridges. Laboratory and field case studies
This paper investigates the use of infrared thermography for detection of moisture behind the surface of masonry arch bridges. The paper will describe both the laboratory experiments and two case studies of masonry arch bridges in Scotland. This is the first application of infrared thermography on masonry arch bridges in the UK. The outcome of this work shows that infrared thermography can generally be used to determine the presence of moisture within the fill of a masonry arch bridge, even in unfavourable weather conditions as found in Scotland. Thermal imagers offer an excellent means of making a qualitative measurement of the temperature of a surface, but absolute temperature measurement is fraught with difficulties. The radiation received from an object is a function of its temperature, spectral emissivity, and reflections from its surroundings along with atmospheric transmission. This means that practical measurements should be undertaken in a temperature-controlled environment allowing time for the object to reach thermal equilibrium with its surroundings. Consideration needs to be given to the fact that, outdoors, many factors alter the surface temperature of the object under investigation. The weather can have a major effect. Sunlight may increase the temperature and wind may decrease the temperature of an object. Rain will lower the temperature of an object through both conductivity and evaporation, it will also cause a change to the emissivity.
Infrared thermography assessment of masonry arch bridges. Laboratory and field case studies
This paper investigates the use of infrared thermography for detection of moisture behind the surface of masonry arch bridges. The paper will describe both the laboratory experiments and two case studies of masonry arch bridges in Scotland. This is the first application of infrared thermography on masonry arch bridges in the UK. The outcome of this work shows that infrared thermography can generally be used to determine the presence of moisture within the fill of a masonry arch bridge, even in unfavourable weather conditions as found in Scotland. Thermal imagers offer an excellent means of making a qualitative measurement of the temperature of a surface, but absolute temperature measurement is fraught with difficulties. The radiation received from an object is a function of its temperature, spectral emissivity, and reflections from its surroundings along with atmospheric transmission. This means that practical measurements should be undertaken in a temperature-controlled environment allowing time for the object to reach thermal equilibrium with its surroundings. Consideration needs to be given to the fact that, outdoors, many factors alter the surface temperature of the object under investigation. The weather can have a major effect. Sunlight may increase the temperature and wind may decrease the temperature of an object. Rain will lower the temperature of an object through both conductivity and evaporation, it will also cause a change to the emissivity.
Infrared thermography assessment of masonry arch bridges. Laboratory and field case studies
Infrarotthermographie zur Bewertung gemauerten Bogenbrücken. Labor- und Feldstudien
Clark, M. (Autor:in) / Forde, M.D. (Autor:in)
2003
12 Seiten, 17 Bilder, 3 Tabellen, 11 Quellen
(Nicht paginiert)
Aufsatz (Konferenz)
Datenträger
Englisch
Laboratory study of infrared thermography on masonry arch bridges
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British Library Online Contents | 2006
| Engineering Index Backfile | 1966
| Engineering Index Backfile | 1957