Due to the lack of a rational method of earth works quality control, density is still used as the governing criterion for compaction acceptance. As discussed, particle breakage may influence the outcome of compaction testing particularly in calcareous sands. In such cases the engineer is provided with very little scope to accept a level of compaction other than that specified. This is despite the Australian Standard stating that over specifying compaction should be avoided. The lack of a rational basis for specifying compaction based on relative compaction has led to a "95 percent fixation". Results of compression tests undertaken on compacted sand demonstrate that specifying density alone may not guarantee soil stiffness. The results by Hellweg and Rizkallah (1980) are of particular interest, as they show an apparent 'yielding' below a certain level of relative density. However, the 'threshold level of compaction' is likely to be highly material dependant. Despite the existence of methods of testing in the field that produce direct correlations with compressibility, they have not been included in AS 3789, despite there being an Australian standard for determining CIV. While these methods continue to be omitted from the AS 3789 it is unlikely that they will be regularly used in earthwork specifications and the engineer will continue to struggle to answer the question: will this level of compaction be adequate?
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