Effect of Shaft Pillar Extraction on Stability of Main Shaft: A Case Study at Xincheng Gold Mine, China

Table 2

Main mechanical parameters of the rock samples retrieved around shaft.

Shaft depth/m	Lithology	Rock movement angle/°	Density/kg/m^3	Young’s modulus/GPa	Poisson’s ratio	UCS/MPa	Internal friction angle/°	Cohesion/MPa
0–33.80	Quaternary overburden	45	-	-	-	-	-	-
33.80–116.18	Cataclastic granite; Sericitolite lithified granite; Sericite & chlorite lithified granite	70	2490	42.7	0.18	50.3	35.75	40
116.18–168.00	Cataclastic granite	65	2570	96.8	0.36	46.4	36.5	32
168.00–225.00	Potassium feldspar & biotite lithified granite	80	2560	67.7	0.30	96.2	32.27	86
225.00–272.00	Sericitolite lithified mylonitic granite	70	2540	39.4	0.16	56.2	36.87	30
272.00–341.53	Sericitolite lithified mylonitic granite; Pyritic phyllic cataclasite	65	2500	41.6	0.28	28.3	33.02	35
341.53–366.89	Pyritic phyllic granite; Sericite & kaolin clay lithified granite	70	2530	46.4	0.16	41.6	33.02	38
366.89–422.00	Biotite granite; Pyritic silicified granite	80	2580	48.2	0.16	79.4	36.87	48
422.00–465.50	Biotite granite	80	2620	49.4	0.18	78.9	33.82	59
465.50–529.74	Phyllic cataclastic granite; Phyllic biotite granite	60	2630	78.8	0.24	63.5	33.22	41
529.74–663.20	Pyritic phyllic cataclasite; Porphyritic granodiorite	80	2620	133.1	0.34	123.8	33.22	51