Fatigue Evaluation Tests for Asphalt Binders and Instabilities in Torsional Flows

Author(s): Abhijith B. S. and Atul Narayan S. P.
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: 396-405
Total Pages: 10
Language : English

Abstract: The Time Sweep (TS) test and the Linear Amplitude Sweep (LAS) test are two of the most
widely accepted tests for characterizing fatigue resistance of asphalt binders. Both tests
involve oscillatory loading on bitumen specimen using a dynamic shear rheometer (DSR)
with parallel-plate geometry. Asphalt cement is subjected to a sinusoidal loading with
constant strain amplitude over a period of time in the TS test. In the LAS test, it is again
subjected to a sinusoidal loading at a fixed frequency. But the amplitude of the applied strain
is increased linearly with time. In this study, TS and LAS tests were conducted while varying
the gap between the parallel plates. It was found that, even when the same strain history is
applied, the response can change significantly with the gap. The lower the separation between
the parallel plates, the higher was the fatigue resistance predicted by the TS and the LAS test
methods. This behaviour is similar to that observed for polymer solutions and polymer melts
by researchers, and can be attributed to the instabilities associated with torsional flows of
nonlinear viscoelastic materials. The findings illustrate the necessity for a new method to
interpret TS and LAS test results.

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