Research on the Resonance Characteristics of Rock under Harmonic Excitation

Table 2

Ultrasonic test results of sandstone cores.

No.	Shape	Size	Resonance frequency (50 kHz) kHz	Amplitude	Resonance frequency (250 kHz) kHz	Amplitude
1	Cylinder	Φ8 cm × 20 cm	62	0.1691	92	0.1763
2		Φ8 cm × 15 cm	63	0.1438	92	0.2845
3		Φ8 cm × 14 cm	67	0.1874	93	0.317
4		Φ8 cm × 10 cm	67	0.1781	93	0.4409
5		Φ8 cm × 5 cm	68	0.4277	204	0.1986
6		Φ8 cm × 3 cm	68	0.4953	204	0.1611
7	Block	10 cm × 10 cm × 10 cm	63	0.5264	186	0.1368
8		5 cm × 5 cm × 5 cm	67	0.6015	197	0.1657
9		4 cm × 4 cm × 4 cm	68	0.4888	206	0.1347