Study on Sound Propagation Performance of Mechanized Coal Gangue-Fine Sand Filling Body

Table 6

Sound wave velocity of filling body specimens in each curing age.

Curing age (d)	Vp/ (km/s)
	1	2	3	4	5	6	7	8	9
5	1.795	1.892	1.750	1.944	1.795	1.667	1.892	1.707	1.556
6	1.892	1.944	1.944	2.059	1.892	1.795	2.059	1.842	1.591
7	2.208	2.000	1.818	2.059	1.842	1.750	1.707	1.707	1.591
8	2.258	2.058	1.842	2.187	2.000	1.556	2.121	1.889	1.647
9	2.413	2.121	2.058	2.333	2.059	1.892	2.147	2.108	1.707
10	2.413	2.187	2.058	2.500	2.187	1.944	2.180	2.108	1.794