Experimental Study on Acoustic Emission Characteristics of Dry and Saturated Basalt Columnar Joints under Uniaxial Compression and Tensile Damage

Abstract EN

An experimental study was carried out to investigate the acoustic emission (AE) characteristics of dry and saturated basalt columnar joints under uniaxial compression and tensile damage by using the TAW-2000 rock experiment system and SH-IIAE system for the whole loading.

The results show that the softening coefficient of uniaxial compressive strength and the tensile strength was 0.78 and 0.68, respectively, and water increases the sample complexity and has a strong effect on its strength.

The dry sample under uniaxial compression at the beginning of loading produced a large number of AE signals, and the AE signal showed steady growth as the load increased, but the sample destruction occurred during the blank period, which can be used as a precursor of instability.

From the amplitude-time-energy diagram, it can be found that as amplitude increases with hit, energy decreases, which shows an obvious triangle relation.

From the uniaxial compression damage AE location map, we can find that AE events exist disorderly and show scattered distribution in each area.

From the failure modes and sections of tension and uniaxial compression tests, it is found that there are many layers and fissures in rock samples, which are consistent with AE location.