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

Table 1

Calculation parameters.

Number	Name	Symbol	Value	Unit	Instruction
1	Width of roadway	L	4.6	m
2	Internal friction angle of rock mass	φ	36	°
3	Rock mass cohesion	C	0.6	MPa	The softening coefficient is 0.47
4	Polar coordinates of roadway floor	θ	−48∼48	°	Refer to Figure 1 for calculation
5	Thickness of beam	d	0.2	M
6	Equivalent friction factor	f	0.15		In this paper, the value is equal to the friction between steel and steel
7	Body force of concrete	γ′	0.024	MN/m^3	The density is 2400 kg/m^3
8	Thickness of concrete	h	0.5	m	Average value