STATIC DETERMINATION OF THE EQUATION-OF-STATE OF CEDAR CITY TONALITE.
Abstract
Static compressibility measurements were made on samples of Cedar City tonalite of nominal densities of 2.37, 2.54, and 2.61 g/cc. The purpose of these measurements was to provide equation-of-state data for code calculations. Water-saturated and dry samples were cycled to 0-12-0-24-0-38-0 kb in a piston-cylinder solid pressure media apparatus. The effect of cycling the dry samples caused the denser samples to expand on cycling; the low density sample showed a large, permanent negative strain after the 0-12 kb cycle. Further crack closure on cycling was elastic. At 40 kb the samples were approaching a density which suggested all the cracks and pores had been removed. The saturated samples behaved much differently than the dry samples. Their delta V was less, their hystersis was less and their compressibility curves reproduced on cycling. Hydrostatic cycling experiments were made to 9 kb using axially and circumferentially mounted strain gages on copper-jacketed rock cylinders. The rocks showed permanent set to pressures of 1 kb. Above 1 kb the cracks and pores appeared to be removed elastically. With a few notable exceptions, the linear compressibilities of all the samples were within 10 percent of each other. Thus, with these exceptions and the exclusion of the lower density (2.37 g/cc) material, the rock seems generally homogenous and isotropic elastically. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1970
- Accession Number
- AD0713175
Entities
People
- Phillip N. La Mori
Organizations
- Battelle Memorial Institute