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The use of laser-interferometry (ESPI) in analysis of reinforced concrete structures
Shear tests at the Institut für Massivbau point out a correlation between the crack angle and the shear reinforcement ratio. The laser-interferometry was used as measuring technique to investigate the influence of nonlinear redistributions on the crack angle before macrocracking. This technique enables displacement-measurements areawise with a grade of accuracy between 10-6 - 10-8 m. The principal strains and their directions can be specified from the displacements. The following conclusions can be drawn from the measurements: - Testing specimens of low shear reinforcement ratio the shear cracks ran flatter than according to a linear elastic calculation for an uncracked specimen. The reason lies within the stress redistributions. - There are nonlinear processes before the visible crack formation. They begin at about 85 % of the load of the visible macrocrack. - The stress-redistributions have a non negligible influence on the inclination of the cracks. The crack inclination is not only determined by the trajectories of the uncracked system but also by the inner structural system during the period of crack formation.
The use of laser-interferometry (ESPI) in analysis of reinforced concrete structures
Shear tests at the Institut für Massivbau point out a correlation between the crack angle and the shear reinforcement ratio. The laser-interferometry was used as measuring technique to investigate the influence of nonlinear redistributions on the crack angle before macrocracking. This technique enables displacement-measurements areawise with a grade of accuracy between 10-6 - 10-8 m. The principal strains and their directions can be specified from the displacements. The following conclusions can be drawn from the measurements: - Testing specimens of low shear reinforcement ratio the shear cracks ran flatter than according to a linear elastic calculation for an uncracked specimen. The reason lies within the stress redistributions. - There are nonlinear processes before the visible crack formation. They begin at about 85 % of the load of the visible macrocrack. - The stress-redistributions have a non negligible influence on the inclination of the cracks. The crack inclination is not only determined by the trajectories of the uncracked system but also by the inner structural system during the period of crack formation.
The use of laser-interferometry (ESPI) in analysis of reinforced concrete structures
Der Einsatz der Laserinterferometrie (ESPI) bei der Untersuchung von Stahlbetonstrukturen
Hegger, J. (author) / Görtz, S. (author) / Niewels, J. (author)
2003
5 Seiten, 5 Bilder, 4 Quellen
(Nicht paginiert)
Conference paper
Storage medium
English
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