ABSTRACT
This chapter summarises the engineering properties of the Hawkesbury Sandstone in two ways. Firstly, data collected from various sites and academic studies have been collected and are presented in tabular, graphical and statistical forms. Secondly, data from selected sites are presented together with the borehole logs from the sites. This second approach helps to illustrate the variability in the properties, particularly highlighting the effects of weathering. The degree of overgrowth development is variable and has an important bearing on the strength and stiffness properties df the material. The spaces between the quartz grains contain dominantly clay but with some secondary silica, iron oxide and mica. An unpublished study by Robson gives meticulously measured mineralogical, grain size and porosity data on 42 samples of Hawkesbury Sandstone taken from 16 locations within the Sydney Basin. In generalising the properties of the Hawkesbury Sandstone, there is a danger of giving the Impression that the properties are quite consistent and uniform across the Sydney Basin.
