Characterisation of a lightly stabilised granular material by indirect diametrical tensile testing

Abstract

Lightly stabilised granular materials with cementitious binders are generally characterised by their stiffness modulus and this paper examines the use of monotonic and cyclic load indirect diametrical tensile (IDT) testing to determine the stiffness characteristics of these materials. The experimental programme included the determination of density, IDT strength and static and dynamic moduli from monotonic and cyclic load IDT testing for a typical freshly quarried aggregate granular base material stabilised by the addition of 3–5% slag–lime slow-setting binder under a narrow range of moisture variations. The IDT tests were conducted on 28 days cured samples prepared by gyratory compaction. Details of an IDT testing arrangement with internal displacement measurement for performing cyclic load testing to obtain reliable data are also discussed. This study indicates that cyclic load IDT testing could be used reliably for determining the dynamic stiffness modulus of a lightly stabilised granular material with a newly proposed equation.

Keywords:

• characterisation
• cementitious binders
• stabilisation
• IDT testing
• lightly stabilised granular
• dynamic stiffness modulus

Acknowledgements

The authors would like to thank Mr David Sharp and Mr Jim Baxter for their technical assistance during the experimental work reported in this paper.

The contributions of Boral Private Ltd and Blue Circle Southern Cement Pty Ltd for providing the granular base and the binder, respectively, that were used in the laboratory testing programme are also acknowledged and appreciated.