Deformation Mechanism and Control Technology of Surrounding Rock in the Deep-Buried Large-Span Chamber

Table 3

Determination of rock mass density.

Lithology	Number	(mm)	(mm)	(kg)	(/m^3)	(/m^3)
Roof siltstone	1-1	48	70	0.33	2.61	2.48
	1-2	48	68	0.34	2.76
	1-3	48	72	0.32	2.46
	1-4	48	71	0.31	2.41
Sandy mudstone of floor	2-1	48	64	0.29	2.51
	2-2	48	65	0.27	2.30
	2-3	48	57	0.25	2.43
	2-4	48	61	0.26	2.36

Note: is diameter; is height; is weight; is density; is average density.