Critical Height of Unfilled Zone in Underlying Gob Piles

Table 2

Numerical simulation schemes.

Scheme	Old goaf width (m)	Coal pillar width (m)	Whether to fill	Filling height (m)	UZHUG (m)
1	16	8	No	0	8
2	16	8	Yes	2	6
3	16	8	Yes	4	4
4	16	8	Yes	6	2