The response of frozen soils to vibratory loads
Abstract
A laboratory test was conducted on prepared specimens of frozen soils in which a right circular cylinder was subjected to steady state sinusoidal vibration. The material was considered to be linearly viscoelastic. Analysis of test data based on one-dimensional wave propagation yielded the complex Young's modulus, the complex shear modulus, the phase velocity of wave propagation, the shear velocity, the damping property, an attenuation coefficient, and a complex Poisson's ratio. The frequency of vibration was varied from 500 to 10,000 Hz, and the peak dynamic stress was varied from 0.1 to 5.0 psi. Specimens were remolded or cored in-situ, frozen, and tested at temperatures of 0, 15 and 25 deg. A few tests were conducted on identical soils nonfrozen. Results from a limited number of tests on selected soils indicate that the stiffness of these soils varies with the volume of ice/volume of soil ratio, and that ice is less stiff than saturated frozen soils. Frozen soils have stiffnesses up to 100 times those of identical soil nonfrozen. Depending upon the degree of ice saturation, the stiffness of non-saturated frozen soils varies from that of the saturated soils to nearly that of the nonfrozen soils. Stiffness increases with decreasing temperature but the rate is relatively low. As temperature rises and approaches the freezing point, stiffness abruptly decreases.
- Publication:
-
Unknown
- Pub Date:
- June 1975
- Bibcode:
- 1975rfsv.rept.....S
- Keywords:
-
- Permafrost;
- Soil Mechanics;
- Vibration Effects;
- Ice;
- Modulus Of Elasticity;
- Poisson Ratio;
- Shear Properties;
- Stiffness;
- Vibration Damping;
- Vibration Tests;
- Wave Propagation;
- Geophysics