Study on Law of Overlying Strata Breakage and Migration in Downward Mining of Extremely Close Coal Seams by Physical Similarity Simulation

Table 3

Similar simulation strata distribution and material mixture ratio.

Number	Lithology	Thickness (mm)	Proportioning	Material consumption (kg)
				Sand	Lime	Gypsum	Water
1	Fine sandstone	136.0	9 : 6 : 4	56.402	3.760	2.507	2.507
2	Siltstone	88.0	8 : 7 : 3	36.045	3.154	1.352	1.622
3	Fine sandstone	30.0	9 : 6 : 4	12.442	0.829	0.553	0.553
4	Sandy mudstone	106.0	10 : 7 : 3	44.404	3.108	1.332	1.954
5	Siltstone	152.0	9 : 8 : 2	63.037	5.603	1.401	2.802
6	Mudstone	84.0	8 : 8 : 2	34.406	3.441	0.860	1.548
7	Medium sandstone	120.0	8 : 6 : 4	49.152	3.686	2.458	2.212
8	Mudstone	188.0	10 : 7 : 3	78.755	5.513	2.363	3.465
9	Coal 9	64.0	10 : 9 : 1	26.810	2.413	0.268	1.180
10	Sandy mudstone	40.0	10 : 7 : 3	16.756	1.173	0.503	0.737
11	Coal 10	44.0	10 : 9 : 1	16.756	1.508	0.168	0.737
12	Siltstone	100.0	7 : 5 : 5	16.128	1.152	1.152	0.737