A new approach on crushing strength test for fibre reinforced concrete pipes

Author(s): A. Figueiredo, A. de la Fuente, C. Molins, A. Aguado
Paper category: Conference
Book title: 8th RILEM International Symposium on Fiber Reinforced Concrete: challenges and opportunities (BEFIB 2012)
Editor(s): Joaquim A.O. Barros
Print ISBN: 978-2-35158-132-2
e-ISBN: 978-2-35158-133-9
Publisher: RILEM Publications SARL
Pages: 1082 - 1095
Total Pages: 13
Language: English

Abstract: 
The fibre reinforced concrete pipes have normally their mechanical behaviour verified through crushing test that follows a cycled procedure. This test is crucial to verify if the pipe fit the mechanical requirements specified in the standards. The conception of this test procedure is based on the premise that no continuous lecture of load and displacement curves will be made. So, only one load value is quantified (maximum load) and two other loads are verified. The first load to be verified is the proof load in the first loading cycle before the peak load. The same load value is verified again at the second loading cycle, at post-peak part of the test when the bearing capacity of the cracked pipe under a fixed load is checked. In that situation, there is no actual determination of the post-crack strength. Thus, a different procedure of testing is proposed, without cycling loading and with continuous data acquisition on load and diameter displacement measurement. A LVDT are used for diametric displacement measurement and it is fixed in a device in order to avoid influence of external deformation. Results published in previous experimental studies focusing in fibre reinforced concrete pipes with different fibre contents were used for the test procedure analysis. A new procedure for the crushing test is proposed based on the approach of the new fib Model Code for structural design of fibre reinforced concrete. The analysis shows that the new test procedure could lead to a better assessment of the pipe during the test, including the pos-peak strength, even when the fibres provide a strain hardening behaviour. In this particular case, the cycled test became unfeasible due to the difficulties associated to the evaluation of correct moment of interruption of the first cycle of loading. Another advantage of the proposed test procedure is to turn possible the future association between the level of displacement and the service life conditions of the component.

Online publication: 2013
Publication Type: full_text
Public price (Euros): 0.00