STRESS CONDITION EFFECTS ON DYNAMIC PROPRETIES OF SOILS

Laboratory tests, using resonant column method, were conducted to evaluate the shear modulus and the damping characteristics in dry and saturated specimens of variable soils in Japan. The hollow cylindrical samples tested were 25 cm in height, 10 cm in outside diameter and 6 cm in inside diameter. After the sample was set and preparations were completed, the frequency of the torsional excitation was varied until the oscillator specimen system resonated. Test results obtained showed such dynamic properties of soils as follows: (1) Under constant values of other parameters, shear moduli vary with 1/2 power of p (the mean principal stress) and decrease with increase of void ratio and shearing strain amplitude. Furthermore, damping capacities decrease with increase of p and increase with increase of strain amplitude. However, damping capacities take constant values irrespective of change of void ratio under constant values of other parameters. (2) While the value of p is kept constant, shear moduli are nearly constant irrespective of the value of q (the deviator stress) until the stress ratio, q/p, reaches some value, say 1.0. However, beyond this value of q/p, shear moduli begin to decrease with increase of q/p. This phenomenon would be due to the anisotropic stress condition and the corresponding anisotropy in the inner structure of specimens.

Media Info

  • Features: Figures; References;
  • Pagination: p. 227-243

Subject/Index Terms

Filing Info

  • Accession Number: 00128529
  • Record Type: Publication
  • Report/Paper Numbers: Tech Memo #1023 Pt I
  • Files: TRIS
  • Created Date: May 14 1976 12:00AM