Accession Number:

AD0423446

Title:

STRESS PROPAGATION IN SOILS.

Descriptive Note:

Final rept., pt. 3,

Corporate Author:

STANFORD RESEARCH INST MENLO PARK CA

Report Date:

1963-05-01

Pagination or Media Count:

202.0

Abstract:

Stress wave propagation experiments in sand were performed with the intention of determining a mathematical model for sand. A combined approach of experiment and analysis was used. The models selected analysis were a linear locking model which exhibits a permanent set after a loading cycle, and the contant tan delta viscoelastic model. Analyses were made of the response of a one-dimensional medium of each material subjected to a theoretical pressure in the form of the overpressure from an aboveground explosion. In the experimental work a blast loading was applied to the top of a column of soil in a tube designed to allow only one-dimensional motion. The required conditions were met in the sand below the top 15 cm and in the center of the tube out to 5 cm from the tube wall. Piezoelectric stress gages and accelerometers embedded in the soil measured soil response. Accelerometer records gave a reliable record of particle velocity in the soil but the recorded stresses were not simply related to the stress in the soil. Further development will be needed for the stress gages. Measurements of soil behavior gave attenuations of acceleration and particle velocity, and an increase in wave velocity with depth for a step input of pressure. Author

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE