Mechanical Characteristic of Buffer/Backfilling Materials After Different Temperatures

摘要

Based on uniaxial compression test, the mechanical properties of buffer/backfilling materials after different temperatures are studied. The study analyzed buffer/backfilling materials of stress-strain curve, peak stress , modulus of elasticity, peak strain, with the variation of temperature. The buffer/backfilling materials of strengthening and degradation in different temperature are discussed briefly. The test result show that below 200°C, buffer/backfilling materials of stress-strain curve of slope, peak stress, modulus of elasticity, peak strain ,are increase with increasing temperature increase. The main reason is that with increasing temperature, adsorbed water in the sample will evaporate, and brittleness of sample will improve;;mineral particles of expansion lead to the original cracks closing, the porosity will reduce, and improve friction properties between particles. 300 °C,buffer / backfill materials of stress - strain curve of slope, peak stress, elastic modulus, decreased to varying degrees compared to 200 °C. the main reason is that thermal stress damage to the internal structure of the samples, resulting in new small cracks. The peak strain of buffer / backfill materials in the 25 °C ~ 100 °C is increase with increasing temperature increase. 100°C-200°C, peak strain is decrease with the increase of temperature. In the 200 °C~ 300 °C, the peak strain change little.