Experimental Investigation of the Anchoring Effect of Two Different Types of Rock Bolts on Fractured Rock
Table 2
Test results of specimens under uniaxial compression.
α (°)
Group number
Type of bolt
Pretension stress (MPa)
E (GPa)
σi (MPa)
σp (MPa)
σr (MPa)
30
1
Unbolted
—
13.30
25.69
33.54
1.82
2
Fully bonded
—
13.81
31.00
35.99
11.70
3
Prestressed
36
13.67
28.23
35.97
13.75
4
Prestressed
60
14.38
30.01
36.26
14.60
45
5
Unbolted
—
12.83
17.49
28.80
4.34
6
Fully bonded
—
14.05
29.12
33.85
12.35
7
Prestressed
36
13.65
20.60
32.22
17.17
8
Prestressed
60
14.20
23.51
33.66
18.47
60
9
Unbolted
—
13.06
28.93
31.28
6.94
10
Fully bonded
—
14.58
33.03
36.40
11.91
11
Prestressed
36
13.96
31.31
33.75
15.85
12
Prestressed
60
14.63
32.14
34.27
16.76
E represents the elastic modulus. σi is defined as the wing crack initiation strength, and σp is defined as uniaxial compressive strength. σr represents the residual strength.
