A New Modified Peck Formula for Predicting the Surface Settlement Based on Stochastic Medium Theory

Table 3

The relevant parameters of the settlement curve of each tunnel depth Z.

Calculation method	Z (m)	i (m)	Smax (mm)	Relative error in width of settlement trough (%)	Relative error in maximum settlement (%)
The modified Peck formula	6	3.52	−96.19	18.0	−15.22
Peck formula		2.98	−113.46
The modified Peck formula	7.5	4.10	−82.44	10.1	−9.18
Peck formula		3.73	−90.77
The modified Peck formula	9	4.83	−70.98	6.6	−6.16
Peck formula		4.47	−75.64
The modified Peck formula	10.5	5.46	−61.96	4.6	−4.44
Peck formula		5.22	−64.84
The modified Peck formula	12	6.17	−54.83	3.4	−3.35
Peck formula		5.96	−56.73