Effects of Back-Pressure Saturation Techniques on Results of R Triaxial Compression Tests.

Abstract

Corps of Engineers (CE) soil laboratories achieve 100 percent saturation of R and R triaxial compression test specimens by the use of back pressure applied in small increments concurrently with increase in chamber pressure with adequate time between increments to permit equalization of pore-water pressure throughout the specimen. The objective of this procedure is to apply sufficient pressure on the pore water and pore air so that the air is dissolved in the pore water without significantly prestressing (overconsolidating) the specimen. The objectives of this investigation were to determine the effects of the magnitude of back pressure and the procedure by which it is applied on the stress deformation characteristics of soils. The objectives were achieved by comparing results of tests performed on compacted specimens of Vicksburg loess (clayey silt (ML)) and Vicksburg buckshot (plastic clay (CH)) in which the back-pressure saturation procedure was varied and results of tests performed on specimens of Vicksburg buckshot consolidated from a slurry in which the magnitude of the total back pressure was varied. The results indicate that variations in the technique of applying back pressure may significantly affect test results.

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Document Details

Document Type
Technical Report
Publication Date
May 01, 1979
Accession Number
ADA071053

Entities

People

  • Frank C. Townsend
  • Robert T. Donaghe

Tags

DTIC Thesaurus Topics

  • Automatic
  • Back Pressure
  • Control Systems
  • Engineering
  • Laboratory Equipment
  • Materials
  • Measurement
  • Mechanics
  • Pore Pressure
  • Pressure Gages
  • Pressure Measurement
  • Pressure Regulators
  • Pressure Switches
  • Pressure Transducers
  • Soil Mechanics
  • Solenoid Valves
  • Test Equipment

Fields of Study

  • Engineering

Readers

  • Geotechnical Engineering.
  • Mechanical Engineering/Mechanics of Materials.