Experiment of Freezing-Thawing Cycles and Analysis of Damage Characteristics for Argillaceous Dolomite

Abstract

For the purpose of research on behavior of argillaceous dolomite suffering from frequent cryogenic freezing weather in Guizhou region, the rock was processed into cylinder samples (diameter 50mm&height 100mm). Using BCD-218 cryogenic digital control equipment, in saturated state, the samples were frozen (-20°C) and thawed (20°C), each 12 hours for one cycle, total 30 times. Then, Longitudinal wave velocity (LWV), macroscale and mass varying with freezing-thawing cycles were respectively tested by RS-ST01C nonmetal supersonic test meter, vernier caliper (0.02mm), APT457A electronic balance (0.01g). Also, appearance characteristics were observed constantly. Lastly, the micro reason for changes in macro parameters of the rock was explained. The results show that the freezing-thawing deterioration form of argillaceous dolomite is spallation mode, and LWV decreases obviously with the increase of freezing-thawing cycles (FTC),maximum drop of 14.8%,while mass has a small increase, maximum change rate of 0.5%. Macroscopic properties are obviously affected by freezing and thawing cycles. Key words: argillaceous dolomite, freezing-thawing cycles, supersonic detection, damage characteristics