Title:
Experimental study of shear transfer in polypropylene fibre-reinforced concrete using pre-cracked push-off specimens
Author(s):
Ortiz-Navas, F.; Scaroni, L.; Navarro-Gregori, J.; Serna-Ros, P.
Publication:
Symposium Paper
Volume:
343
Issue:
Appears on pages(s):
91-100
Keywords:
Push-off, shear crack, PFRC, SFRC, Shear behaviour.
DOI:
Date:
10/1/2020
Abstract:
Shear transfer mechanisms in fibre-reinforced concrete (FRC) have been studied by many authors based on push-off specimens. However, only few studies have used pre-cracked pushoff
specimens to examine the real shear and normal stresses transferred through the crack. In this paper it is presented the experimental results of twenty-one pre-cracked push-off specimens tested under direct shear. Specimens were manufactured using plain concrete (PC), polypropylene fibre-reinforced concrete (PFRC), and steel fibre reinforced concrete (SFRC). In PFRC and SFRC specimens, fibre was dosed in 10kg/m3 and 30kg/m3 respectively. Nevertheless, both types of dosages were selected in order to provide similar post-cracking behaviour to the specimens. Five types of pre-crack openings were set up (W = 0, 0.25, 0.50, 0.75 and 1.0 mm) by an external steel frame system that confined the specimens during the
tests. Afterwards, pre-cracked specimens were tested under direct shear where the crack kinematic (opening and slip displacements) as well as stresses (shear and normal) were recording during the tests. Finally, a comparison of behaviour between PC, SFRC and PFRC is
done. Experimental results show the ability of both fibres to increase shear stress as well as shear stiffness in FRC specimens compared to PC ones. Moreover, it is evidenced that both type of fibres provided similar shear improvements despite of being different in material and shape.
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