The Relationship between Mining-Induced Stress and Coal Gas under an Optimized Support Scheme: A Case Study in the Guanyinshan Coal Mine, China

Table 2

Mechanical properties of anchor cable materials [25, 26].

Type of anchor cables	Structural steel strand	Diameter (mm)	Breaking load (kN)	Extension (%)
Ordinary anchor cable		15.20	260	3.50
		17.80	353	3.50
		18.90	409	3.50
		21.60	530	3.50
High-strength prestressed anchor cable		18.00	399	6.50
		20.30	504	6.50
		21.80	582	7.00
		28.60	900	7.00