Relative density and median grain-size correlation from laboratory compaction tests on granular soil

Laboratory tests on 55 clean sand samples were conducted to determine the maximum and minimum void ratios (e_max and e_min) and the void ratios at the optimum water content from standard and modified Proctor compaction tests (e_s and e_m). The void ratios [e_max, e_mine_s, and e_m] and, hence, the relative density of compaction (D_r) have been correlated to the median grain size (D₅₀) of soils. Predicted values of D_r give results within a range of ±5% compared to those obtained from laboratory tests. The proposed expressions are valuable in compaction control of earthwork and would be well received in the development of compaction specifications.