Document: NRC Regulatory Guide
Document ID: 1859c547-c10c-4ce4-ad2e-e54f7b66d4ef
Document Type: regulatory_guide
Title: Laboratory Investigations of Soils and Rocks for Engineering Analysis and Design of Nuclear Power Plants + HISTORY – HISTORY 07/2014 – DG-1256 , Proposed Revision 3 08/2001 – DG-1109 , Proposed Revision 2 (Rev. 3)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1318/ML13186A032.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.138
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CFR Title: 

Content:
dication that the boring samples were disturbed. Personnel should not use disturbed samples for any test other than classification and tests that do not require an undisturbed sample. When a sample is disturbed, its seal may be broken and that sample cannot be used for water content. DG-1256, Page 8 4.3. Reconstituted or Remolded Samples a. All tests of strength and dynamic responses of in situ soils, whether cohesive or cohesionless, should use high-quality, undisturbed samples. In some instances, however, reconstituted or remolded samples may be used when representative undisturbed samples cannot be obtained. Remolded samples are also used as representative of compacted fill or backfill material for new construction. Reconstituted specimens representative of in situ material should be molded to the in situ density and moisture content as determined from actual field measurements. 4.4. Scalping of Large Particles a. Since standard-size laboratory testing equipment will not readily accommodate gravel and large particles, such materials should be removed from the total sample, and the finer fraction tested. For additional information on accounting for large particles, Torrey and Donaghe (1991, Ref. 24) discuss fractional analysis of density for compaction control measures to account for scalped gradation and Evans and Zhou (1995, Ref. 25) report the effects on cyclic strength of the inclusion of gravel size particles in various gradations of granular soils. 4.5. Laboratory Testing Program a. The study of soil and rock mechanics covers the investigation, description, classification, testing, and analysis of soil and rock to determine their interaction with structures built in, upon, or with them. The physical properties of soils and rocks should be determined by carrying out tests on samples of soil in a laboratory. These tests fall into two main categories: classification tests and engineering properties tests. Classification tests indicate the general type of soil