Fracturing of the Soft Rock Surrounding a Roadway Subjected to Mining at Kouzidong Coal Mine

Table 1

Rock material and mass properties.

Lithology	Rock specimens properties				Rock mass properties
	mi	Density (kg/m^3)	Poisson’s ratio	Ei (GPa)	GSI	c (MPa)	Tci (MPa)	Φ (deg)	Emass
Mudstone	5	2773	0.12	17.5	45	11.74	3.73	18.66	3.91
Siltstone	9	2680	0.2	19.5	65	3.75	1.84	38	12.32
Sandstone	19	2681	0.26	56	35	11.74	6.87	18.66	6.35
13-1 Coal	14	1329	0.36	17.5	30	4.57	1.63	35.21	1.42
Sandy mudstone	6	2510	0.15	10.85	29	2.45	2.01	40	0.83
Medium sandstone	15	2580	0.2	5.99	60	4	1.2	37	3.11
Fine sandstone	17	2873	0.15	10.85	55	3.75	1.84	3.75	4.43