CONSOLIDATION AND FLOW CHARACTERISTICS OF PEAT

RESEARCH WAS CONDUCTED ON CONSOLIDATION AND LOAD-BEARING CHARACTERISTICS OF PEAT. LARGE-SCALE CONSOLIDATION TESTS WERE CONDUCTED TO INVESTIGATE THE BEHAVIOR OF PEAT UNDER LOADING. THE FACTORS UNDER CONSIDERATION WERE THE RATE OF COMPRESSION AND THE BUILD-UP AND DISSIPATION OF PORE WATER PRESSURES. IT IS SHOWN THAT WHEN AMORPHOUS-GRANULAR PEAT IS SUBJECTED TO LOADING, THE COMPRESSION IS COMBINATION OF TWO PROPERTIES: (1) THE PERMEABILITY WHICH GOVERNS THE RATE AT WHICH WATER CAN BE SQUEEZED OUT OF THE PEAT, AND (2) THE VISCOUS FLOW PROPERTIES OF THE PEAT. THE LARGE-SCALE CONSOLIDATION TESTS SHOWED THAT THE PORE WATER PRESSURES, IMMEDUATELY AFTER LOADING, WERE CONSIDERABLY LESS THAN THE THEORETICAL VALUE AND THE PORE WATER PRESSURES INCREASED TO A VALUE SLIGHTLY LESS THAN THE THEORETICAL VALUE DURING THE EARLY PART OF THE PROCESS. A COMPARISON BETWEEN THE EXPERIMENTAL CURVE AND THE THEORETICAL CURVE SHOWS THAT PLASTIC STRUCTURAL DEFORMATIONS TAKE PLACE AT A RAPID RATE IN THE EARLY STAGES OF CONSOLIDATION, AS THERE IS A DECREASE IN PORE WATER STRESS WITH A CONSEQUENT INCREASE IN EFFECTIVE STRESS. THE DEFORMATION IS A COMBINATION OF VOLUME CHANGE AND LATERAL FLOW OF THE PEAT. THE REASON FOR THE DISCREPANCY OF PEATS FROM THE CLASSICAL THEORY OF CONSOLIDATION ARE THAT STRUCTURAL DEFORMATIONS ARE CAUSED WHEN PEAT IS LOADED, PEAT IS A NON-NEWTONIAN FLUID, THE CHANGE IN PERMEABILITY WITH CHANGE IN VOID RATIO IS SIGNIFICANT, AND THE PLASTIC STRUCTURAL RESISTANCE CAUSES MORE PORE WATER PRESSURES THAN THE THEORETICAL VALUES.

• Supplemental Notes:
  • No 81, pp 150-160, 4 FIG, 5 REF
• Authors:
  • Wilson, N E
  • Adams, J I
  • Scott, J D
  • Radforth, N W
• Publication Date: 0

Media Info

• Serial:
  • Ncr Soil & Snow Mech Tech Memo /Can/

Subject/Index Terms

• TRT Terms: Bearing capacity; Consolidation; Deformation; Effective stress; Loads; Peat soils; Permeability; Pore water pressures; Soils; Viscous flow; Void ratios; Volume changes
• Uncontrolled Terms: Loading; Soil consolidation; Soil deformation
• Old TRIS Terms: Soil bearing capacity; Soil permeability
• Subject Areas: Geotechnology; Highways;

Filing Info

• Accession Number: 00229882
• Record Type: Publication
• Files: TRIS
• Created Date: Sep 28 1970 12:00AM