Implementation of Paste Backfill Mining Technology in Chinese Coal Mines

Table 1

Performance table of PL backfilling cementing materials and 42.5 level normal cement.

Kind of aggregate	Cementing materials (kg·m^−3)		Compressive strength (MPa)
	Variety	Dosage	8 h	1 d	3 d	7 d	28 d
Fine sand from Si River	PL	80	0.16	0.70	1.45	1.88	2.43
		100	0.31	1.00	2.13	2.71	3.38
		150	0.63	1.54	3.25	4.33	5.47
		250	1.22	2.07	6.22	8.34	10.2
	Cement	100	0	0.29	0.63	0.92	2.13
Loess from Huozhou	PL	80	0	0.18	0.30	0.38	0.51
		100	0	0.36	0.47	0.63	0.79
		120	0.22	0.47	0.71	0.85	1.10
		150	0.41	0.66	0.91	1.15	1.47
	Cement	100	0	0	0.16	0.31	0.72
		120	0	0	0.20	0.36	1.07
		150	0	0	0.31	0.58	1.58
Gangue	PL	200		0.54	1.73	3.74	6.40
		250		1.58	3.79	5.20	7.24
		300		2.90	5.28	6.62	9.94
	Cement	200		0.51	0.84	1.04	1.63
		250		0.58	1.29	1.49	2.45
		300		0.66	1.71	2.16	3.61