Consulting civil engineer, and former assistant chief, U. S. Bureau of Reclamation, Wheat Ridge, Colo.
Pages: 13 Published: Jan 1973
To evaluate the density of free draining cohesionless soils in terms of percent relative density, there are three parameters that must be determined. These are (1) the minimum density that the soil can be structured, (2) the maximum density that the soil can be structured, and (3) the density of the soil being evaluated. Errors or variations can be obtained in determining each of these three values. The reasons for such variations include (1) lack of specimen similarity, (2) dissimilar test procedures used, (3) testing equipment not similar or not properly maintained, and variations in the training and expertise of operator. The results of a large number of tests by numerous laboratories indicate that the variations associated with the minimum and maximum density tests are about the same as those associated with the impact compaction tests. The requirement for determination of three parameters to determine the relative density value can lead to the compounding of errors and variations in the worst cases. The use of proper test methods, closely followed; specified equipment, well maintained; well trained test personnel, and care in sampling should provide reproducible relative density values within 10 percent relative density.
cohesionless soils, density (mass/volume), tests, soils, reproducibility, soil compacting, reliability, soil mechanics
Paper ID: STP37861S