Shales are often viewed with suspicion as embankment construction materials becaouse of their characteristically low strength and poor durability. Typically, shale deposits are nonhomogeneous and problems are encountered in selecting compaction specifications which will insure a uniformly densified fill. Past experience with shales in Indiana suggests that embankment instability is caused at lest partly by the presence of large voids, and the collapse of shale pieces into these voids as slaking occurs. It has been hypothesized that the gradation of shale particles before compaction and the degradation that occurs during copaction control the size and distribution of voids within the fill. Four types of laboratory compaction test have been performed on a model shale to measure the particle degradation and its relation to compaction effort and unit weight. From these results, a static compaction test is recommended as a compaction-degradation index to be used to compare various shales. Additionally, the Scleroscope hardness test and point load strength test have been considered as indices of the engineering properties of shales. Long term soaking tests on two shales were performed. From these it appears that the effect of moisture is extremely complex. Further research will be required to define this relation and translate it into improvements in the state of the art of shale embankment construction. /Author/

  • Supplemental Notes:
    • Prepared in cooperation with the Department of Transportation, Federal Highway Administration.
  • Corporate Authors:

    Purdue University/Indiana Department of Transportation JHRP

    Purdue University, School of Civil Engineering
    West Lafayette, IN  United States  47907-1284
  • Authors:
    • Bailey, M J
  • Publication Date: 1976-8

Media Info

  • Features: Appendices; Figures; References; Tables;
  • Pagination: 230 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00163663
  • Record Type: Publication
  • Report/Paper Numbers: JHRP-76-23 Intrm Rpt.
  • Contract Numbers: HPR-1(14) Part II
  • Files: TRIS
  • Created Date: Jan 13 1978 12:00AM