Evaluation of Physical Properties of Rocks in Forced Deterioration Experiments

To investigate deterioration rate of rocks, the authors conducted measurements of the physical properties of naturally weathered Kimachi sandstone and forcedly deteriorated Kimachi sandstone. The naturally weathered Kimachi sandstone was obtained by boring from a surface after excavation which had not been touched for approximately 100 years. From the Measurement results of the physical properties of the naturally weathered Kimachi sandstone, the relationship between these properties, depth and time was obtained. The forced deterioration experiments were carried out by repeated drying-wetting and drying-wetting-freezing-thawing cycles. The experiment results revealed that the decrease in ultrasonic wave speed with each cycle approximated well with the logarithmic function.