THE ENGINEERING CLASSIFICATION OF RESIDUAL TORPICAL SOILS

THE SOIL CLASSIFICATION COMMONLY USED IN SOIL MECHANICS WORK HAS BEEN EVOLVED FOR STABLE TEMPERATURE CLIMATE SOILS AND IS UNSUITABLE FOR TROPICAL SOILS. A CLASSIFICATION BASED ON THE PARENT ROCK AND ITS DEGREE OF WEATHERING IS RECOMMENDED AS THE ONLY PRACTICABLE ONE FOR ENGINEERING PURPOSES. IT HAS BEEN USED NOW FOR SOME YEARS WITH CONSIDERABLE SUCCESS WHEREAS THE TEMPERATE CLIMATE CLASSIFICATION HAS HAD TO BE DISCARDED FOR TROPICAL SOILS. THE TERM "LATERITE" HAS BECOME MEANINGLESS. IN SPITE OF PROTESTS, ITS APPLICATION IS NOW SO WIDE THAT IT IS USELESS AS A DESCRIPTION WITH ANY PRETENSIONS TO SCIENTIFIC EXACTITUDE. IT CANNOT BE USED EXCEPT IN THE MOST GENERAL WAY AS, FOR EXAMPLE, WE USE THE TERM BOULDER CLAY. THE TYPES OF SOIL CONSIDERED ARE RESIDUAL. THAT IS, THEY ARE THE RESIDUE RESULTING FROM IN SITU WEATHERING OF THE PARENT ROCK UNDER THE INTENSE CONDITIONS OF TROPICAL CLIMATE - HIGH TEMPERATURES AND RAINFALL. GENERALLY SPEAKING, THE WEATHERING PROCESS OF TROPICAL SOILS IS INCOMPLETE AND THE MATERIALS CAN EXIST AT ALL STAGES FROM THE FRESH ROCK TO SOIL. THE WEATHERED MATERIALS ARE MECHANICALLY UNSTABLE; THE PARTICLES ARE LIABLE TO BREAK DOWN UNDER HANDLING, FOR EXAMPLE, WHEN THE MATERIAL IS BEING SAMPLED. THE CLASSIFICATION PROPOSED IS VERY SIMILAR TO THAT DEVISED BY MOYE FOR THE SNOWY MOUNTAINS AUTHORITY. IT IS COMPARED WITH THIS AND ALSO WITH THAT PROPOSED BY RUXTON AND BERRY FOR HONG KONG SOILS AND, MORE RECENTLY ONE BY WARD ET AL FOR THE WEATHERING OF CHALK. /RRL/A/

• Supplemental Notes:
  • Vol 1, pp 1-10, 2 FIG, 2 TAB, 16 REF
• Authors:
  • Little, A L
• Conference:
  • Soil Mech & Fdn Eng Conf Proc /Mexico/
• Publication Date: 0

Media Info

• Serial:
  • Issue Number: 0

Subject/Index Terms

• TRT Terms: Atmosphere; Climate; Residual soils; Rocks; Soil mechanics; Soil types; Tropics; Weathering
• Uncontrolled Terms: Soil classification
• Subject Areas: Geotechnology; Highways;

Filing Info

• Accession Number: 00229361
• Record Type: Publication
• Source Agency: Road Research Laboratory /UK
• Files: TRIS
• Created Date: May 26 1971 12:00AM