Effect of Prestress on the Bond Strength of Pretensioned Concrete Systems

Author(s): Prabha Mohandoss and Radhakrishna G. Pillai
Paper category: Proceedings
Book title: Proceedings of the 71st RILEM Annual Week & ICACMS 2017,Chennai,India, 3rd -8th September 2017
Editor(s): Manu Santhanam
Ravindra Gettu
Radhakrishna G. Pillai
Sunitha K. Nayar
ISBN: 978-2-35158-196-4
ISBN: 978-2-35158-190-2 (Set)
e-ISBN: 978-2-35158-191-9:
Publisher: Published by RILEM Publications S.A.R.L.
Publication year: 2017
Pages: 178-185
Total Pages: 8
Language : English

Abstract: The structural performance of pre-tensioned concrete (PTC) systems depends on the
performance of strand-concrete (SC) bond. The bond mechanism in PTC systems is mainly
contributed by three factors: adhesion, mechanical interlock, and friction. This mechanism can
be influenced by various factors like concrete strength, prestress level, type of strand, the
surface condition of the strand, etc. Different test methods are existing to determine the bond
strength of PTC systems. However, those test methods do not consider the prestress level and
thus, do not represent the actual condition of the PTC systems. This study presents an
experimental study on the bond strength of PTC systems with prestressed seven-wire strands.
Prismatic PTC specimens with (100 100) mm cross section and containing a prestressed
strand are used for determining the bond strength (using pull-out tests). Two prestress levels of
0.1 fpu (taut specimen) and 0.7 fpu (stressed specimen) are used. The length of the taut and
stressed specimens were 500 and 1000 mm, respectively. Concrete with an average
compressive strength of 64 MPa was used. It was expected that the stressed specimen would
exhibit higher bond strength than the taut specimen. However, the 1000 long stressed
specimens exhibited about 20% less bond strength than the 500 mm long taut specimens.

Online publication : 2017
Publication type : full_text
Public price (Euros) : 0.00