Quantitative Visualization Monitoring of Cracks at Shotcrete-Rock Interface Based on Acoustic Emission

Table 2

Basic information of shotcrete-rock specimens.

Specimens	Interface roughness levels	Rock types	Strength of concrete (MPa)
HB	B	Granite	54.67
HC	C	Granite	54.67
HD	D	Granite	54.67
SD	D	Sandstone	54.67