Investigation into the effect of size on the shear strain rate and the uniaxial compressive strength using finite difference simulation

The uniaxial compressive strength is one of the most important mechanical properties of rocks as its assessment is necessary in various rock engineering projects. Statistically the number of larger discontinuities present in larger specimens is larger and the compressive strength is thus lower, as various research show that the uniaxial compressive strength decreases with an increase of rock specimen size. It has not been investigated whether the size affect the strength and rate of shear strain by finite difference simulation using FLAC3D software or not. Specimens having 10 different sizes have been modeled under uniaxial compressive load using FLAC3D software in this research. The results show that uniaxial compressive strength (UCS) and rate of shear strain decrease by power functions with an increase of specimen size. The size is also more effective on the uniaxial compressive strength and rate of shear strain for specimen having smaller size, as size effect is negligible for larger specimens having diameter of about 6 m and onward.

کلیدواژه ها:

Uniaxial strength compression ، Scale effect ، Modeling ، Shear strain rate