NCHRP Web-only Document 164: Precision Estimates of AASHTO T265: Laboratory Determination of Moisture Content of Soils

摘要

This report presents the results of an interlaboratory study (ILS) to prepare precision estimates for AASHTO T265 test method used for Laboratory Determination of Moisture Content of Soils. The materials for the ILS included two coarse- and two fine-grained soil-aggregate blends that were prepared according to Grading A and Grading E of AASHTO M147, Materials for Aggregate and Soil-Aggregate Subbase, Base, and Surface Courses. Each of the four blends had less than 10% soil passing No. 200 sieve to represent suitable materials for base and subbase. The comparison of the statistics of moisture content data for the four soil-aggregate blends indicated that the variability of moisture content measurement is the same for the blends with clay and silt; however, the variability is different for the blends with fine and coarse gradations. A precision statement for AASHTO T265 that includes the precision estimates developed in this study has been prepared and provided in the report.