Date of Award
Fall 2021
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Mechanical Engineering
First Advisor
Borg, Joun P.
Second Advisor
Erdinez, Dinc
Third Advisor
Fournelle, Raymond A.
Abstract
A generalized P-Lambda equation of state and strength model (dependent on hydrostatic and deviatoric stress terms) for porous alpha phase crystalline quartz under compression load was generated utilizing Copper Mountain sandstone (from Mosinee WI) and augmented with existing petrographic data. Tests with Copper Mountain sandstone samples began with an examination of elastic properties before conventional low strain rate testing was conducted. Sample thickness varying from ~0.5 mm to ~3.0 mm, were tested in high strain rate plane strain and pressure-shear configurations at impact velocities from 3 m/s to 720 m/s. Each plane strain test contained multiple sandstone samples so that differences in thickness can be compared within a given shot. The particle velocity induced at the back surface of the sample was measured using a Photon Doppler Velocimetry (PDV) system. Thus, the variations wave development as a function of sample thickness can be assessed. Pressure-shear experiments were performed in order to determine the strength characteristics of the sandstone samples. The dynamic experiments were simulated utilizing CTH and compared with experimental results.