Influence of Existing Defects on Mechanical Properties of NC Lining

Table 2

Calculation conditions.

Calculation conditions	Defect position	Load direction	Void range	Thinning ratio	Stratum stiffness (MPa/m)
1∼48 (48)	Crown	45°, 0°	0°, 15°, 30°, 45°, 60°, 75°	—	27.9, 150, 400, 850
49∼92 (44)	Spandrel	90°, 0°	0°, 15°, 30°, 45°, 60°, 75°	—	27.9, 150, 400, 850
93∼116 (24)	Crown	90°, 45°, 0°	—	0.25%, 50%	27.9, 150, 400, 850
117∼140 (24)	Spandrel	90°, 45°, 0°	—	0.25%, 50%	27.9, 150, 400, 850
141∼220 (80)	Crown	45°, 0°	15°, 30°, 45°, 60°, 75°	25%, 50%	27.9, 150, 400, 850
221∼300 (80)	Spandrel	90°, 0°	15°, 30°, 45°, 60°, 75°	25%, 50%	27.9, 150, 400, 850