The classification of chalk for use as a fill material

this report describes an investigation of chalk as a freshly placed fill material and the development of a new classification for chalk in relation to the stability of the material during construction. from measurements made on eleven chalk earthworks sites the onset of unstable conditions in the fill has been related to values of moisture content and degree of crushing. the proposed classification is based on the prediction of these two parameters and depends on the measurement of the saturation moisture content and the impact crushing value (using a newly developed test) of the chalk. the classification includes recommendations on the selection, when necessary, of methods of earthwork construction which minimise the risk of instability in the freshly placed material, while at the same time using a degree of compaction compatible with a satisfactory long-term performance of the embankment.(a)