Effect of Weathering on Strength and Modulus of Basalt and Siltstone
Abstract
Engineering properties, such as Unconfined Compressive Strength (UCS), qu and Young’s Modulus, E, of mass rock have a significant effect on project design and construction operation of the rock-structure interface. A better understanding the rock engineering properties can provide a base for a more rational approach to design of civil engineering works. The estimation of rock engineering properties has historically relied on subjective assessments of rock mass quality and measurements of intact values. A recent project in Melbourne, Australia, has provided an opportunity to test rock core-samples from nearly 200 boreholes along an approximately 12 km’s length of a sewerage tunnel alignment in both Siltstone and Basalt. This paper presents some previously unpublished laboratory testing data on the engineering properties of Siltstone and Basalt. Also included is an examination of the important influence of moisture content and the degree of weathering on the mechanical properties - particularly the qu and E parameters. The present findings show a good agreement with the results of previous studies on the mechanical properties of both Siltstone and Basalt.
2008
American Rock Mechanics Association (ARMA) Conference Proceedings
D. X. Gu
Sinclair Knight Merz
W.Tamblyn
Sinclair Knight Merz
Isabelle Lamb
Jacobs Associates
N. Ramsey
Sinclair Knight Merz