Differential Analysis and Prediction Optimization of Ground Surface Settlement Induced by Quasi-Rectangular Shield and Pipe Jacking Tunnelling

Table 1

Model size and structural parameters.

Name	X (m)	Y (m)	Z (m)	E (GPa)	Neutral pillar	Reduction factor	Equivalent layer (m)
Shield	172	67	42	20.7 (C50)	Yes	0.6	0.2
Pipe jacking	84	67	42	34.5 (C50)	No	1.0	0.06