Study on mechanical properties and acoustic emission characteristics of deep diorite under uniaxial compression

• DOI: 10.1016/j.heliyon.2024.e24482
• Publication Date: 2024-01-11T07:49:09Z
• Authors: Kai-De Liu; Yu Zhou; Xiao-Ping Zhang; Shao-Jun Fu; Quan-Sheng Liu; Peng Dong; Kai-Wen Yao; Ding-Bo Wang
• Keywords: Acoustic Emission; Diorite

The research object is diorite in the Lingbei TBM section of Hanjiang-To-Weihe River Qinling tunnel, with a buried depth over 1 km. Using MTS-2000 microcomputer-controlled electro-hydraulic servo universal testing machine and DS5-16b acoustic emission (AE) monitoring system, uniaxial compression tests were carried out on rock samples, to study mechanical properties characteristics deep diorite. results indicate that: (1) During compression, undergoes four stages: initial compaction, elasticity, yield failure, which curve compaction stage significantly smoother. compressive strength 41.95 MPã102.42 MPa, an average 74.07 Mpa; axial peak strain ranges from % 1.4 %, failure mode belongs brittle ductile splitting failure. (2) cumulative ringing count energy showed very slow increase trend during calm period; After entering surge period (with appearance Kaiser points), both show significant transition state; period, overall growth rate two slowed down remained almost silent. (3) On basis analysis RA-AF values deformation rupture process diorite, it can be seen that damage type tensile by low RA value high AF characteristics, coincides actual fracture rocks sample. (4) stage, there are few location points, correspond mainly distributed at higher lower ends sample; elasticity number positioning points increases gradually expands towards middle; Near point, corresponding sharp state, this good agreement changes count-time energy-time curves. (5) time starts end pattern change localization point evolution. used as referential for development excavation, protection other construction plans tunnel or similar surrounding tunnels, well further conducting triaxial unloading