4
Table 1. Summary of the key features of all SEPTs
Mine Coal seam
Number
of Tests
Rebar
Diameter
(mm)
Bolt
Length
(m)
Average
Peak
Load
(kN)
Load
Range
(kN)
Average Peak
Displacement
(mm)
Rotation
Speed
(rpm)
A No 2 Gas
5 19.05 1.219 115 69–134 15 n/a
5 15.875 1.219 22 10–34 6 n/a
B Pittsburgh 3 15.875 1.219 52 48–58 19 n/a
C Pittsburgh 6 15.875 1.219 47 24–72 17 n/a
D Kellioka 7 15.875 1.219 72 36–111 9 n/a
E Pocahontas No. 3
2 15.875 1.219 45 40–50 23 n/a
2 15.875 1.524 63 52–73 22 n/a
F Jawbone 3 19.05 1.524 98 93–101 20 n/a
NIOSH Safety
Research Mine Pittsburgh
3 19.05 1.219 107 98–112 19 170
6 19.05 1.219 79 17–61 25 780
3 15.875 1.219 103 90–109 18 170
6 15.875 1.219 46 17–61 9 780
Figure 2. Load-displacement curves for SEPTs