Table 1 Mechanical parameters of the surrounding rock as determined through laboratory testing.
Serial number | Monitoring items | Sensor name | Monitoring frequency | ||
|---|---|---|---|---|---|
1 ~ 15d | 16d ~ 1mo | 1 ~ 3mo | |||
1 | Crown settlement and horizontal convergence | Total station and convergence meter | 1 ~ 2times/d | 1times/2d | 1 ~ 2times/wk |
2 | Surrounding rock pressure | Earth pressure cell | 1 ~ 2times/d | 1times/3d | 1 ~ 2times/wk |
3 | Surface stress and strain of steel arch support | Surface strain gauge | 1 ~ 2times/d | 1times/3d | 1 ~ 2times/wk |
4 | Reinforcement stress of secondary lining | Rebar strain gauge | 1 ~ 2times/d | 1times/3d | 1 ~ 2times/wk |
5 | Concrete stress | Concrete strain gauge | 1 ~ 2times/d | 1times/3d | 1 ~ 2times/wk |
6 | Pore water pressure | Pore water pressure gauge | 1time/d | 1time/3d | 1time/wk |
