Stability Analysis and Confidence Level Evaluation of Backfill Mining under High and Steep Rock Slopes

Table 5

Standard values and the calculated stability safety factors of HSRS.

Items	Codes or methods	In normal operation		In seismic conditions
		Open-stope	Backfill	Open-stope	Backfill
Calculation results	Simplified Bishop method	1.561	1.636	1.383	1.536
	Fellenius method	1.480	1.551	1.381	1.445
	Simplified Janbu method	1.485	1.539	1.376	1.428
Average calculation		1.509	1.575	1.380	1.470
Chinese standard values	Code for investigation of geotechnical engineering	1.30∼1.50		1.20∼1.40
	Technical code for building slope engineering	1.35		1.15
	Technical code for noncoal open-pit mine slope engineering	1.20∼1.25		1.15∼1.20
Biggest standard values		1.50		1.40