A Method Based on Elastic Mechanics for Judging Compound Hard Roof and Its Application

Table 4

Similar material proportioning of 8101 working face.

No.	Model height (cm)	Density (kg/m^3)	Ratio NO. (River sand: Line: gypsum)	River sand (kg)	Line (kg)	Gypsum (kg)	Water (L)	Sodium tetraborate (kg)
1	16.63	1730	373	168.34	39.28	16.83	22.45	0.22
2	4.27	1689.33	437	44.98	3.37	7.87	5.62	0.06
3	6.20	1689.33	437	65.36	4.90	11.44	8.17	0.08
4	3.17	950.67	473	18.79	3.29	1.41	2.35	0.02
5	9.98	1689.333	637	112.72	5.64	13.15	13.15	0.13
6	6.98	1689.33	437	73.58	5.52	12.88	9.20	0.09
7	15.51	1689.333	637	175.21	8.76	20.44	20.44	0.20
8	6.95	1689.33	437	73.23	5.49	12.81	9.15	0.09
9	5.72	1689.33	437	60.30	4.52	10.55	7.54	0.08
10	4.27	1730	373	43.25	10.09	4.32	5.77	0.06
11	6.73	1689.33	437	70.98	5.32	12.42	8.87	0.09
12	6.38	1689.333	637	72.06	3.60	8.41	8.41	0.08
13	1.63	1689.333	637	18.45	0.92	2.15	2.15	0.02
14	10.72	1818.67	437	121.66	9.12	21.29	15.21	0.15
15	3.49	950.67	555	21.59	2.16	2.16	2.59	0.03
16	8.08	1818.67	437	91.70	6.88	16.05	11.46	0.11
17	6.00	1730	864	71.97	5.40	3.60	8.10	0.08
18	2.20	950.67	473	13.05	2.28	0.98	1.63	0.02
19	1.07	1730	864	12.79	0.96	0.64	1.44	0.01
20	14.01	950.67	473	83.13	14.55	6.23	10.39	0.10
21	20.00	1730	373	202.41	47.23	20.24	26.99	0.27
22	10.00	1689.33	437	105.4144	7.90608	18.44752	13.1768	0.131768