Study on Antiseismic Effect of Different Thicknesses of Shock Absorption Layer on Urban Shallow Buried Double Arch Rectangular Tunnel

Table 4

Principal stress and antiseismic effect.

Condition	Maximum principal stress		Minimum principal stress
	Maximum value (Pa)	Antiseismic effect (%)	Maximum value (Pa)	Antiseismic effect (%)
1	3.231 × 10^6	—	−5.816 × 10^6	—
2	2.780 × 10^6	13.96	−5.258 × 10^6	9.59
3	2.756 × 10^6	14.70	−5.124 × 10^6	11.90
4	2.779 × 10^6	13.99	−5.000 × 10^6	14.03