Concrete strength dependent pull-out behavior of deformed steel fibers

Author(s): K. Wille
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: 123 - 135
Total Pages: 12
Language: English

Abstract: Single fiber pull-out tests on deformed high strength steel fibers embedded in ultra-high performance concrete (UHPC) have been performed to analyse the bond properties. Two types of high strength steel fibers, one commercially available end hooked fiber and one manufactured twisted fiber, have been included in this research. The research emphasis has been laid on the analytical distinction between physico-chemical and mechanical bond. Based on prior pull-out test results other researchers’ this research analyses the strength dependent pull-out behavior of hooked and twisted fibers embedded in concrete matrixes with compressive strength ranging from 28 MPa (4ksi) to 192 MPa (28 ksi). Evaluation parameters include the maximum induced fiber tensile stress, the equivalent bond strength and the unit pull out work per embedded fiber surface area. The equivalent bond strength of deformed fibers embedded in UHPC reaches 47 MPa (6.8 ksi) in maximum, this is almost 5 times higher than the equivalent bond strength of the same fibers (10 MPa (1.4 ksi)) embedded in normal strength concrete. By considering the analytical distinction between physico-chemical and mechanical bond it is pointed out that an inappropriate strong mechanical bond damages the matrix and thus does not lead to an optimal pull-out behavior.

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