Report No. : GEO Report No. 41

Report Title : Mineralogy and Fabric Characterization and Classification of Weathered Granitic Rocks in Hong Kong (1996), 158 p.

Author : T.Y. Irfan

Abstract

The behaviour and engineering properties of weathered rocks are controlled by the mineralogy and fabric characteristics of the rock material as well as the discontinuities within the rock mass. In the saprolites and residual soil, the influences of discontinuities are greatly reduced and the mineralogy, grain size, microfabric and the bonding characteristics (i.e. soil microstructure) become more dominant in controlling engineering properties and in-situ behaviour. To date, these properties have not been well documented for weathered rocks and soils in Hong Kong.

As part of its research and development programme, the Geotechnical Engineering Office has been looking into ways of determining and characterising the mineralogical and fabric properties of weathered rocks, in particular the soil grades, with the objective of understanding their behaviour in the laboratory and in the field. This document summarizes the study results on the mineralogical and fabric properties of the weathered granitic rock within the context of a revised material and mass weathering classification scheme and makes particular reference to the effects of their specific mineralogy and microstructure on the soil classification and index properties and behaviour.

Download Document(s)