Changes in Mechanical Properties of Rocks Exposed to Alternate Dry and Wet Conditions

• Published in: Shigen to sozai Vol. 108; no. 1; pp. 51 - 56
• Main Authors: ICHINOSE, Masatomo, MATSUI, Kikuo, GOTOH, Ken
• Format: Journal Article
• Language: Japanese; English
• Published: The Mining and Materials Processing Institute of Japan 1992
• Subjects: Dry and Wet; Mechanical Property; Pore Volume; Rock; Slaking
• ISSN: 0916-1740; 1880-6244
• DOI: 10.2473/shigentosozai.108.51

It is of great importance to understand and know of the relationship between the mechanical properties of coal measure rocks and water content, in maintaining of mine roadways and utilizing mine waste rocks as packing and backfilling materials. From this point of view, changes in mechanical properties of rocks, which are classified mainly into Palaeogene, exposed to alternate dry and wet conditions are investigated by laboratory tests. The measurements of pore volume and pore size distributions of these rocks are carried out with mercury penetration method. The results are summarized as follows; 1) Slaking rocks exhibit remarkable deterioration in the mechanical properties even after a few times of repetition of dry and wet condition, whilst non-slaking rocks exhibit little. 2) Pore volume increases with times of repetition untill the onset of slaking. 3) These phenomena indicate that deterioration of mechanical properties is due to increased pore volume, namely microcracks.