Indirect Tensile versus Two-point Bending Fatigue Testing

Date

2008-11

Advisors

Journal Title

Journal ISSN

ISSN

0965-092X

Volume Title

Publisher

ICE Publishing

Type

Article

Peer reviewed

Yes

Abstract

This paper describes a comparison between an indirect tensile fatigue method and the currently preferred European standard two-point bending, trapezoidal fatigue test. A study was undertaken using both tests to determine the fatigue properties of a standard UK asphalt mixture at two temperatures of 10 and 30°C. The fatigue life, in addition to using the traditional 90% reduction in initial stiffness, was also computed using a fatigue failure point based on the transition between the quasi-stationary phase (associated with a uniform stiffness decrease and the development of micro-cracks) and the failure phase (associated with localised crack propagation). This fatigue failure point, determined by taking the peak of the product of loading cycles and stiffness versus loading cycles, was also converted into an alternative form used to determine the fatigue failure point for the indirect tensile fatigue test. Separate fatigue relationships were produced for the four combinations of test method and temperature based on the phenomenological initial tensile strain versus fatigue life relationship. Although the indirect tensile fatigue test produced shorter fatigue lives compared to the two-point bending fatigue test, it was also possible to combine all four fatigue relationships to produce one unique fatigue function for the 20 mm dense bitumen macadam asphalt mixture.

Description

Keywords

fatigue, bitumen and tar, strength and testing of materials

Citation

Cocurullo, A., Airey, G.D., Collop, A.C. and Sangiorgi, C. (2008) Indirect Tensile versus Two-point Bending Fatigue Testing. Proceedings of the ICE - Transport, 161 (4), pp. 207-220

Rights

Research Institute

Institute of Artificial Intelligence (IAI)