Prediction on Ground Settlement Deformation and Influence of Urban Buildings in the Construction Process of Existing Tunnel Reconstruction

Table 2

Material physical and mechanical parameters of calculation model.

Material	Density	Elastic modulus	Poisson’s ratio	Internal friction angle	Dilatancy angle	Stress flow rates
	(kg/m^3)	(GPa)		(°)	(°)
Surrounding rock	1900	0.095	0.35	25	15	1.0
Tube shed layer	2200	10.0	0.25	30	20	1.0
Primary lining	2300	23.0	0.2
Secondary lining	2400	28.0	0.2
Existing tunnel structure	2350	25.0	0.2