Deferred Deflexions with Time of Bamboo Guadua Angustifolia Kunth under Permanent Loads
S. Chavarro, C. Takeuchi
Abstract. In the research “Deflections of Guadua angustifolia Kunth culms under bending stresses with permanent loads in the environment of Bogota. Burger’s and Findley’s models”, it was found, that compared with the Burgers’ models, the Findleys’ models were more appropriate to describe de curve of deferred deflections in time for bamboo Guadua angustifolia Kunth under permanent loads with different stress levels. To determine this, bending tests in guadua culms with short and long duration loads were performed. In the short-duration tests, the failure stress was determined. On the other hand, long-duration tests were performed on samples with different stress levels ranging between 95% and 30% of the average failure stress obtained from a representative short-duration tests with a standard speed loading. Deferred deflections and failure times of the long-duration samples were also registered. In some cases, for culms with low stress level, the load was retired after 280 days with out that the failure of the culms had presented. The Burger and Findley’s models were applied to each one of the time-deflection curves of the long duration tests. The Findley’s and Burger’s models estimated with records of deflections of the total duration of the tests, had correlation coefficients of 0.99 and 0.88 respectively.
Keywords
Duration of Load, Permanent Loads, Deferred Deflections, Bamboo Guadua angustifolia Kunth
Published online , 20 pages
Copyright © 2018 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: S. Chavarro, C. Takeuchi, ‘Deferred Deflexions with Time of Bamboo Guadua Angustifolia Kunth under Permanent Loads’, Materials Research Proceedings, Vol. 7, pp 65-84, 2018
DOI: https://dx.doi.org/10.21741/9781945291838-8
The article was published as article 8 of the book Non-Conventional Materials and Technologies
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