The characteristics of expansive materials are listed, and comments are made regarding the effects of expansive materials on structures, preventive measures, the causes of swelling, and the shearing of water and sewer laterals. One preventive measure is to avoid mass grading i.e. design structures to fit the natural ground contours. If, however, mass grading is a requisite, it should be done by using nonexpansive fill and by properly keying into the adjacent hillside. Swelling associated with moisture changes is attributed to three moisture sources: lawn and plant irrigation, rainwater runoff, and broken water and sewer laterals. Proper drainage and durther measures (specified) must be initiated to reduce these moisture changes. Flexible pipes could be located in creep areas and pipes could be placed above the ground or be backfilled with an impervious clay rather than the traditional sand backfill. If the magnitude of pressure caused by swelling can be bracketed, it may be possible to increase the foundation bearing pressure to resist these uplifting pressures.

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00141313
  • Record Type: Publication
  • Report/Paper Numbers: ASCE #11590 Proceeding
  • Files: TRIS
  • Created Date: Oct 26 1976 12:00AM