Evolution Mechanism of Thickly Sticky Loose Layered Arch Structure and Prediction Method of Initial Ground Fissure Caused by Underground Coal Mining

Table 3

Prediction of ground fissures in typical working faces in Shendong mining area.

Name of coalface	Drill hole name	Loose layer thickness/m	Loose layer type	Initial fracture distance from stop line/m
				Theoretical value	Measured value	Error
Halagou Mine 22207	Q29	40.6	Arch beam destruction type	25.39	26.5	4.19%
Shiyatai Mine 22306	K72	43.2	Arch beam destruction type	60.3	63	4.29%
Halagou Mine 22413	Q104	43.55	Arch beam destruction type	130.5	135	3.33%
Shangwangang Mine 12401	R102	13.95	Loaded type	90.1	94	4.15%
Daliuta Mine 52305	J178	22.45	Arch beam destruction type	129.7	134.2	3.35%