Shigen-to-sozai, Vol.116, No.7, pp.565-571.
Influence of Water and Loading Rate on Deformation and Failure Behavior of Shirahama Sandstone
Yasuyuki FUJITA1, Yoshiaki FUJII2 and Yoji ISHIJIMA2
| 1. Graduate Student, Hokkaido University, 2. Division of Structural and Geotechnical Engineering, Graduate School of Engineering, Hokkaido University, Kita-ku, Sapporo 060-8628 |
| Uniaxial compression tests, Brazilian tests and fracture toughness tests were carried out on dry and wet specimens of Shirahama sandstone at several loading rates. Effects of water in the uniaxial compression tests were as follows: (1) UCS and Young's modulus decreased by 42 % to 47 % and 42 % to 46 %, respectively; (2) Poisson's@ratio increased slightly; and, (3) No obvious effects were observed on the critical strains. Effects of loading rate@were as follows: (1) IJCS and Young's modulus decreased as loading rate decreased; (2) No obvious effects were observed on Poisson's ratio; and, (3) Critical compressive strain and the absolute value of the critical extensile@strain decreased as loading rate decreased. It was clarified in the fracture toughness and Brazilian tests that the fracture toughness / indirect tensile strength decreased by 70 % to 80 % / 52 % to 72 %, respectively, and that a positive linear correlation was observed between fracture toughness I indirect tensile strength and logarithm of loading rate, respectively. Mechanisms of the above observations were discussed based on the breakage of interlocking between such mineral particles as quartz and plagioclase. Breakage of cementing by illite was also considered. |
| KEY WORDS: Shirahama Sandstone, Water, Loading Rate, Uniaxial Compression Test, Brazilian Test, Fracture Toughness Test |