Investigation on Methods of Determining the Grouting Quality of Embedded Rock Bolts Using High Frequency Guided Waves

Table 1

1#–5# peak ratio data.

Specimen	Gain (dB)	Peak value of the first wave packet	Peak value of the second wave packet	Peak ratio
1#	20	0.651	0.109	0.167
	22	0.839	0.141	0.168
	25	1.171	0.200	0.171
	30	2.083	0.354	0.170
	35	3.704	0.639	0.173
2#	20	0.640	0.037	0.059
	25	1.139	0.073	0.064
	30	2.025	0.135	0.067
	35	3.601	0.247	0.069
	40	6.404	0.4441	0.069
	45	11.388	0.784	0.069
3#	5	0.634	0.049	0.078
	8	0.890	0.072	0.081
	10	1.123	0.093	0.083
	15	1.998	0.170	0.085
	20	3.552	0.237	0.067
	25	6.317	0.427	0.068
	30	11.233	0.754	0.067
4#	20	0.453	0.020	0.044
	25	0.804	0.040	0.050
	30	1.431	0.075	0.053
	35	2.545	0.138	0.054
	40	4.525	0.248	0.055
	45	8.047	0.440	0.055
	50	14.310	0.766	0.054
5#	35	0.558	0.013	0.024
	40	0.979	0.028	0.029
	45	1.752	0.053	0.030
	50	3.116	0.096	0.031
	55	5.541	0.179	0.032
	60	9.853	0.313	0.032
	65	17.521	0.476	0.027
	70	31.158	0.747	0.024