Dynamic Response of Parallel Overlapped Tunnel under Seismic Loading by Shaking Table Tests

Table 4

Loading conditions.

	Input motion	Direction	Peak acceleration ()
Case 0	Sine wave	X	0.05
Case 1	El-Centro	X	0.1
Case 2	El-Centro	X	0.15
Case 3	El-Centro	X	0.2
Case 4	El-Centro	X	0.3
Case 5	El-Centro	X	0.4
Case 6	El-Centro	X	0.6