中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 32 No. 7 July 2022 |
（1. Engineering Research Center of Safety and Protection of Explosion & Impact of Ministry of Education (ERCSPEIME), Southeast University, Nanjing 211189, China;
2. School of Civil Engineering, Southeast University, Nanjing 211189, China;
3. State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan 430071, China）
Abstract:This study aimed to elucidate the strength weakening effect of high static pre-stressed rocks subjected to low-frequency disturbances under uniaxial compression. Based on the uniaxial compressive strength (UCS) of granite under static loading, 70%, 80%, and 90% of UCS were selected as the initial high static pre-stress (σp), and then the pre-stressed rock specimens were disturbed by sinusoidal stress with amplitudes of 30%, 20%, and 10% of UCS under low-frequency frequencies ( f ) of 1, 2, 5, and 10 Hz, respectively. The results show that the rockburst failure of pre-stressed granite is caused by low-frequency disturbance, and the failure strength is much lower than UCS. When the σp or f is constant, the specimen strength gradually decreases as the f or σp increases. The experimental study illustrates the influence mechanism of the strength weakening effect of high static pre-stress rocks under low-frequency dynamic disturbance, that is, high static pre-stress is the premise and leading factor of rock strength weakening, while low-frequency dynamic disturbance induces rock failure and affects the strength weakening degree.
Key words: deep rock; high static pre-stress; low-frequency dynamic disturbance; strength weakening effect; uniaxial compression; rockburst
