ASSESSMENT OF THE EFFECTIVENESS OF A VERTICAL MOISTURE BARRIER

A vertical moisture barrier, 2.44 M deep, was used in the rehabilitation of an urban freeway section, to correct a chronic expansive clay roughness problem. Subsurface soil conditions are characterized by routine geotechnical identification tests and mineralogical analysis of the clay fraction. The moisture barrier has been in place for about three years. The evaluation of the barrier's performance is based on periodic surveys of surface roughness, and corroborated by field monitoring the matrix suction potential on both sides of the barrier. The pavement surface condition survey included: roughness spectra, percentage of distressed surface area determined by photologging, and the present serviceability index for both the test section and an adjacent control section. The matrix potential records span through the last two years. For this purpose, thermal block sensors were calibrated in the laboratory and then installed on both sides of the barrier at three different depths. The effectiveness of the barrier is manifested by the lower loss of serviceability index and a lower percentage of distressed area within the test section relative to the control section. This is further corroborated by the matrix potential record which shows that those soils inside the barrier have maintained a fairly constant matrix potential level, while those outside exhibited quite drastic changes. (Author/TRRL)

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/0858252198
• Supplemental Notes:
  • Proceedings of the Fifth International Conference on Expansive Soils, Adelaide, South Australia, 21-23 May, 1984.
• Corporate Authors:

  Institution of Engineers

  11 National Circuit
  Barton, A.C.T.,   Australia 
• Authors:
  • Picornell, M
  • Lytton, R L
  • Steinberg, M L
• Conference:
  • Proceedings of the Fifth International Conference on Expansive Soils, Adelaide, South Australia, 21-23 May, 1984.
• Publication Date: 1984

Media Info

• Features: Figures; References; Tables;
• Pagination: p. 354-358
• Serial:
  • Issue Number: 84/3

Subject/Index Terms

• TRT Terms: Boreholes; Clay; Conferences; Driver rehabilitation; Evaluation and assessment; Expansive clays; Freeways; Geotechnical engineering; Highways; Mathematical matrices; Measures of effectiveness; Mineralogy; Moisture barriers; Moisture content; Paved shoulders; Pavement performance; Roughness; Seal coats; Sensors; Smoothness; Subsoil; Swelling soils
• Uncontrolled Terms: Effectiveness; Rehabilitation; Vertical
• Geographic Terms: United States
• Old TRIS Terms: Pavement serviceability ratings
• ITRD Terms: 5711: Bore hole; 4177: Clay; 8525: Conference; 9020: Evaluation (assessment); 3071: Evenness; 2916: Hard shoulder; 2755: Highway; 6494: Matrix; 5920: Moisture content; 6120: Sensor; 2930: Subsoil; 5203: Swelling (soil); 8122: USA; 9087: Vertical; 2913: Waterproofing course (in the road structure)
• Subject Areas: Geotechnology; Highways;

Filing Info

• Accession Number: 00389717
• Record Type: Publication
• Source Agency: ARRB
• ISBN: 0-85825-219-8
• Files: ITRD, TRIS, ATRI
• Created Date: Mar 29 1985 12:00AM