Experimental on the porosity changing of water-saturated granular limestone during its creep

A test system determining the seepage properties of over-broken rock was used to carry out the creep test for water-saturated granular limestone.By regression,the relationship between the changing rating of the porosity and the current porosity and the stress level during the creep was obtained.This study indicated that when the stress remains a constant level,the changing rating of the porosity can be fitted as a cubical parabola of current porosity;the coefficients of the polynomial depend on the ratios of the axial stress over to the uniaxial compression strength of the rock,and can be expressed as functions of the ratios mentioned above.