Development and Application of Blast Casting Technique in Large-Scale Surface Mines: A Case Study of Heidaigou Surface Coal Mine in China

Table 1

Coal occurrence conditions of major opencast fields in China.

Coal fields	Coal seam				Overburden thickness/m	Rock property of overburden	Overall stripping ratio/m^3·t^−1
	Average coal thickness/m	Number of main minable seams	Seam inclination/(°)	Structure
Pingshuo	30	3	<10	Simpler	100~200	= 4~6	5.59
Zhungeer	33.65	3	5~10	Simple	0~110	= 3.4~6	5.59
Shenfu	17.73	3	1~2	Simple	23~60	Medium hard	6.16
Dongsheng	10.4~27	2	1~2	Simple	<70	Medium hard	2~5
Shengli	34.23	5	3~4	Simpler	0~200	Medium hard	2.5~2.6
Hebaopian	34.7	1~6	5~10	Simple	100~170	Medium hard	4~6
Yinmin	42	2~3	3~6	Simple	5~20	= 1~2	3.13
Huolinhe	10~30	4	5~15	Complex		= 4~5	4~5
Yuanbaoshan	76.7	2	3~8	Simpler		Soft-medium hard	3.96
Baorixile	44.82	5	5~10	Simpler	20~100	Medium hard	3.87
Zhaotong	18~55	3	3~10	Simple		Soft	1.6
Xiaolongtan	70		8~20	Simple		Soft	0.84
Wulumuqi		2	45	Complex