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

Table 4

Physical and mechanical parameters of rock (ore) layers.

Code of stratum	Name of stratum	Volume-weight		Cohesion (kN/m^2)	Internal friction angle (^°)
		t/m^3	kN/m^3
Z2dn2	Grey dolomite	2.76	27.08	470	36
Z2dn1	Light grey dolomite	2.76	27.08	470	36
Z2d4	Grey—charcoal grey dolomite	2.74	26.88	450	36
Z2d3	Grey—charcoal grey argillaceous dolomite	2.70	26.49	430	36
Z2d2^2	Black dolomite with lenticular mass chert	2.80	27.47	480	36
Z2d2^1	Grey dolomite	2.75	26.98	460	36
Ph2	Grey dolomitic phosphorite	2.95	28.94	500	39
Z2d1^3	Grey thick-layer dolomite	2.78	27.27	480	36
Ph1^3	Grey dolomitic phosphorite, grey black tight phosphorite, black argillaceous phosphorite	2.93	28.74	490	39
K2	Potassium-bearing shale	2.68	26.29	330	25
Ph1^2	Black argillaceous sandy phosphorite	2.90	28.45	480	39
K1	Potassium-bearing shale	2.68	26.29	330	25
Z2d1^2	Grey dolomite	2.72	26.68	440	36
Mantlerock	The strong weathering layer	2.50	24.53	150	20
Backfill	Cemented backfill	1.95	19.13	200	22