Stability Mechanism and Repair Method of U-Shaped Steel Reverse Arch Support in Soft Floor Roadway

Table 2

Mechanical parameters for surrounding rock and coal.

Number	Name	γ (MN/m^3)	E (MPa)		σt (MPa)	C (MPa)	Φ (°)
1	Mudstone	0.0257	4800	0.32	1.05	0.6	36
2	Fine sandstone	0.0291	28840	0.18	4.75	3.38	42
3	Medium-grained sandstone	0.026	6800	0.26	2.3	3.7	34
4	Coal	0.0142	2410	0.29	0.36	0.41	21
5	Concrete	0.023	25500	0.2	1.6	3.18	45