Group

1

2

3

4

5

6

Surrounding-rock pressure value/kPa

90.28

123.04

157.14

203.06

131.98

159.63

Group

7

8

9

10

11

12

Surrounding-rock pressure value/kPa

104.09

151.27

138.13

144.62

132.66

138.78

Group

13

14

15

16

Surrounding-rock pressure value/kPa

98.96

103.08

184.63

192.39