Rapid Assessment and Classification for Seismic Damage of Mountain Tunnel Based on Concentric Circle Method
Table 4
Discretized assessment index and description of lining damage.
Damage level
Seismic damage description
Discrete value
Extremely severe
Intensive crack or dislocation (l > 10 m, mm); developing deformation; cracked vault lining is likely to fall; crushed vault lining range S > 3 m2; extremely severe falling of secondary lining, even massive collapse to threaten traffic safety; inrushing groundwater
4
Severe
Crack or dislocation (5 m < l < 10 m, 5 mm < w mm), cracked vault lining is likely to fall; crushed vault lining range 1 m2 < S < 3 m2; continuously inflowing groundwater
3
Moderate
Crack or dislocation (l < 5 m, 1 mm < < 5 mm); small-scale lining peeling-off; crushed vault lining range S < 1 m2; dripping groundwater
2
Slight
Crack or dislocation ( mm) but not further development; no crushed vault; slight seepage of groundwater
1
Undamaged
No cracks or crush; no groundwater seepage; no abnormal phenomenon
0
Note: L = length of crack, = width of crack, and S = area of crushed range.