ENTRAPPED AIR EFFECTS ON SOIL SUCTION MEASUREMENTS

THE PARTICLE INTERACTION CHARACTERISTICS IN A SOILWATER SYSTEM MAY BE MEASURED AND DESCRIBED IN TERMS OF SOIL SUCTION OR MOISTURE POTENTIAL. THE TWO MOST COMMON TECHNIQUES FOR MEASUREMENT OF SOIL SUCTION UTILIZE EITHER THE RICHARDS PRESSURE METHOD OR THE HAINES TENSION APPARATUS. THE CHARACTERISTIC SOIL SUCTION OR MOISTURE POTENTIAL CURVE OBTAINED BY THE PRESSURE TECHNIQUE MAY NOT REPRESENT THE ACTUAL CONDITION OF THE SOIL-WATER AS ALLOWED BY THE HAINES TENSION METHOD. A THEORETICAL EXPRESSION IS DERIVED RELATING MOISTURE POTENTIAL WITH CHANGES IN PRESSURE WHICH MAY BE RELATED DIRECTLY TO THE VOLUME OF ENTRAPPED AIR. THE SUCCESSFUL USE OF THE EQUATION DERIVED DEPENDS ON THE ABILITY TO PROVIDE VALUES FOR VOLUMETRIC ENTRAPPED AIR CONTENT AND ESTIMATION OF THE COMPRESSION OF TRAPPED AIR BUBLES. THIS DEVELOPMENT IS RESTRICTED BECAUSE OF THE DIFFICULTY IN MEASURING THE RATE AT WHICH THE TRAPPED AIR MAY BE INCREASING OR DECREASING. THE DIFFERENCES IN TENSION RECORDED BY THE TWO TECHNIQUES LEAD TO THE CONCLUSION THAT THE TENSIOMETER METHOD WOULD PROVIDE A MORE REALISTIC PICTURE OF THE TENSION IN THE SOIL WATER.

Media Info

  • Media Type: Print
  • Pagination: pp 64-65
  • Monograph Title: Physical and physico-chemical properties of soil, processed soil and rock
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00237196
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Nov 18 1994 12:00AM