Evaluating the Effect of Mix Design Variables on Flexibility Index from Semicircular Bend Test at Intermediate Temperature

Author(s): Hussain Bahia(1), Cheng Ling(1), Remya Varma(1), Daniel Swiertz(1) and Pouya Teymourpour(2)
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: 566-575
Total Pages: 10
Language : English

Abstract: The Semi-Circular Bend Test was recently modified to develop the Illinois Flexibility Index
Test (I-FIT). The I-FIT test quantifies the cracking resistance of asphalt mixtures using the
Flexibility Index (FI), which includes the fracture energy and post-peak behavior of a mixture.
This paper presents results of testing asphalt mixtures that are used currently in Wisconsin
using the I-FIT procedure to differentiate among mixtures based on changes in mixture
composition and aging treatments using a statistical analysis approach. Mixtures varied in RAP
contents, design traffic levels, binder grades, modification levels, and aging conditions are
included in the study. In addition, a laboratory experiment to evaluate the effects of mixture
production variability including asphalt content and filler content on the I-FIT testing results
was performed to provide a basis of evaluating the current production tolerance limits, and set
reasonable specification criteria. The statistical analysis indicates that the FI clearly shows the
ability to discriminate the effect of aging among mixtures; however, the test could not
discriminate the effects of varying levels of percent binder replacement for the mixtures tested
in this study using the I-FIT procedure. It is clear that the FI parameter is sensitive to the
variation in production asphalt content within the tolerances of the current WisDOT
construction specifications, therefore caution should be taken in setting the limits for
acceptance when this test is used for acceptance.

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