Physical Simulation of the Water-Conducting Fracture Zone of Weak Roofs in Shallow Seam Mining Based on a Self-Designed Hydromechanical Coupling Experiment System

Table 2

Model hierarchy and proportion schemes.

Lay number	Lithology	Thickness (1 : 200)		Stratified number	Layered thickness (cm)	Sand (kg)	Gypsum (kg)	Vaseline (kg)	Silicone oil (%)
		Original rock (m)	Model (cm)
1	Mudstone	24	12	6	2	9.72	0.54	0.54	4
2	Coarse sandstone	18	9	5	2	9.45	0.54	0.81	0
					2	9.45	0.54	0.81
					2	9.45	0.54	0.81
					1.5	7.09	0.41	0.61
					1.5	7.09	0.41	0.61
3	Muddy siltstone	6	3	2	1.5	0.72	0.45	0.45	2
4	Mudstone	4.6	2.3	1	2.3	11.18	0.62	0.62	4
5	Middle sandstone	8	4	2	2	9.45	0.64	0.70	0
6	Fine sandstone	8	4	2	2	9.45	0.81	0.54	0
7	Mudstone	11	5.5	3	2	9.72	0.54	0.54	2
					2	9.72	0.54	0.54
					1.5	7.29	0.41	0.41
8	Fine sandstone	8	4	2	2	9.45	0.81	0.54	0
9	Mudstone	6.4	3.2	2	1.6	7.78	0.43	0.43	2
10	Siltstone	12	6	3	2	9.45	0.68	0.68	0
11	Carbonaceous mudstone	8	4	2	2	9.72	0.43	0.65	1
12	21-1 coal	4	2	1	2	9.81	0.39	0.59	0
13	Mudstone	10	5	1	5	24.30	1.35	1.35	4