USE OF GEOGRIDS IN WATER LOGGED AREAS

In Pakistan, the water table in some areas has risen quite close to the ground surface, resulting in failure of many roads. The main objective of this study was to examine the structural suitability and economic viability of using geogrids in road construction in waterlogged areas, especially where the subgrade material is weak. To date, two test sections, each 100 m long, have been constructed on the Jahangira-Swabi road. Both consist of a conventional flexible pavement with granular subbase, crushed stone base, and an asphaltic concrete wearing course. On one of these test sections a geogrid material was placed over the top of the subgrade. The two sections have been monitored for about three years. The section with the geogrid remains in perfect condition with no sign of deterioration on the pavement surface. The other section, however, without geogrid, is distressed with cracking at most of the locations monitored. Ruts have formed in the wheel paths and rut depth measurements ranged from 20 mm to 40 mm. It was concluded that: (1) geogrid material is a cost effective, permanent solution for the construction of roads in the waterlogged areas of Pakistan; (2) geogrid is effective in stabilizing and reinforcing soils, establishing interlock between the subbase particles and the grid; (3) considerable savings can be achieved in reducing gravel layer thickness by using geogrid material; (4) savings in time and money can be achieved by the use of geogrid reinforcement; (5) additional savings are derived from deferred periodic maintenance and rehabilitation; (6) no special equipment or expertise is required for the installation of the geogrids; (7) there is no risk of corrosion as in steel strips; and (8) geogrids do not deteriorate, but give permanent reinforcement, eliminating maintenance and replacement costs.

• Supplemental Notes:
  • Date on title page is June 1996; date on cover is May 1996.
• Corporate Authors:

  Pakistan Ministry of Communications

  National Transport Research Centre
  Islamabad,   Pakistan 
• Authors:
  • Sharif, T
• Publication Date: 1996-6

Language

• English

Media Info

• Features: Appendices; Photos;
• Pagination: 50 p.

Subject/Index Terms

• TRT Terms: Cost effectiveness; Flexible pavements; Geogrids; Geotextiles; Measures of effectiveness; Performance evaluations; Test sections
• Uncontrolled Terms: Effectiveness
• Geographic Terms: Pakistan
• Old TRIS Terms: Waterlogged areas
• Subject Areas: Geotechnology; Highways; Materials; I33: Other Materials used in Pavement Layers;

Filing Info

• Accession Number: 00728405
• Record Type: Publication
• Report/Paper Numbers: NTRC-187
• Files: TRIS
• Created Date: Nov 11 1996 12:00AM