Strengthening of pre-stressed I-roof-beams with external post-tension
Author(s): |
Ilkka Vilonen
Ralf Lindberg Nina Velling |
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Medium: | conference paper |
Language(s): | English |
Conference: | 35th Annual Symposium of IABSE / 52nd Annual Symposium of IASS / 6th International Conference on Space Structures: Taller, Longer, Lighter - Meeting growing demand with limited resources, London, United Kingdom, September 2011 |
Published in: | IABSE-IASS 2011 London Symposium Report |
Year: | 2011 |
Abstract: |
This paper handles strengthening of pre-stressed I-beams. During last year's, in Finland, many buildings were built using pre-stressed pre-fab concrete beams. Trying to reach very low cross-sections, concrete industry forgot to check the compression in concrete. This caused several problems. To solve these problems and create a system to strengthen these beams, Tampere University of Technology planned a testing pattern of specimens with span of 15 meters. Test samples were loaded until brake. At the same time a post-tensioning technique was used to strengthen these beams. The study is handling the strengthening system and influence of its geometric variation. A simple formula to estimate the influence of systems geometric variation was developed according calculation results. Results showed that developed technique is very effective and the formula gives reliable results. |
Keywords: |
testing strengthening prestressing pre-stressing concrete beam repairing
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