Uniform Placement of Sand

The Waterways Experiment Station employed the raining technique, involving free fall of sand to the specimen surface. Fot the gradation of sands used in this experiment, the circular rainer with a perforated plate was found to be the most satisfactory rainer and was adopted for the remainder of the study. Additional study study is required to develop a placement technique that will be satisfactory for placing gap graded and well-graded cohesionless soils homogeneously. As a result of this work it has become apparent that particular attention must be paid to uniformity of density within a lift for large size, laboratory constructed specimens of cohesionless material. In particular, the assumption of uniform density and the determination of a single density value in each lift could lead to misinterpretation of results in model tests in large specimens, where results may be influenced by local areas of varying density. /ASCE/