Statistical Quality Control: Phase Vi, Soils: Statistical Specification for Pug Mill Mixed Materials

摘要

The report of the study discusses the present system of accepting or rejecting pug mill mixed materials and gives the variabilities of the properties of the materials as calculated from samples obtained from 14 plants in Virginia. As a result of this study a new approach to acceptance testing of pug mill mixed materials has been developed. Specifically, the new approach is based on job mix and process tolerances, and acceptance or rejection of a lot is based on the mean of four samples. Special provisions based on this study and prepared by the Department are attached to the report. (Author)