Comments are made on the merits and shortcomings of purposive and random sampling, and the risks of using haphazard sampling. The point is made that the choice of any sampling methodology is not only guided by certain salient features, but is also determined by the type of operation. Points which need clarification by the authors are noted. It is noted that in order to minimize the increase of the engineer's and owner's risks inherent in haphazard sampling, the number of experienced inspectors should be increased to benefit from purposive sampling. The importance is emphasized of sound engineering as well as adequate and reliable supervision for the relevant project. Experienced inspection is essential and indispensable to assure the basic construction quality control from all aspects beyond the testing and figuring of compaction, density, water content, etc. A second discusser agrees that field density tests should be made at locations selected by the continuously present inspector as being likely to have the lowest density of material being placed (purposive sampling) instead of testing randomly. The importance of visual inspection is noted, and comments are made on the control of the density of test fills, the compaction of gravel shells, and the evaluation of the reliability of control procedures.

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00141326
  • Record Type: Publication
  • Report/Paper Numbers: ASCE #11552 Proceeding
  • Files: TRIS
  • Created Date: Oct 26 1976 12:00AM