Mechanical Properties of Deep Buried Altered Hard Rock Under True Triaxial Compression in Sanshandao Gold Mine

doi:10.12068/j.issn.1005-3026.2022.11.011

Abstract

Abstract: The triaxial loading tests and the acoustic emission monitoring tests were carried out three types of altered rocks buried in the depth by using the true triaxial loading system and the acoustic emission monitoring system. The deformation， strength， crack evolution process and microscopic failure mechanism of the altered rocks were analyzed. The experimental results show that the mechanical properties of the three types of altered rocks are quite different due to the influence of the dynamic metamorphism and alteration. After alteration， rock sample with high calcite content becomes brittle， and the failure process is severe accompanied by fast release of elastic energy. The strength of the altered rock suffered from severe dynamic metamorphism and carbonate alteration can be reduced， so its ability to resist deformation is weakened and being vulnerable to be damaged.High content of dolomite in the alteration products can lead to the deflection of crack propagation.

Key words: true triaxial; compression; altered rock; acoustic emission (AE); rupture process

CLC Number:

TU458

YANG Cheng-xiang， CHEN Xiang-yan， ZHOU Jian-hua. Mechanical Properties of Deep Buried Altered Hard Rock Under True Triaxial Compression in Sanshandao Gold Mine[J]. Journal of Northeastern University(Natural Science), 2022, 43(11): 1599-1606.

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