Study on the Division of the Affected Zone under Construction Unloading and Its Construction Sequence of the Multiline Parallel River-Crossing Pipe Jacking

Table 1

Physical and mechanical parameters of the strata.

Stratigraphic type	Elastic modulus E (Mpa)	Poisson’s ratio	Heavy γ(kN/m^3)	Cohesion c(kPa)	Friction angle φ (°)	Thickness (m)
Fill soil	8.0	0.27	18.00	10	10.0	0.5∼1.5
Silty, powdery clay	3.2	0.27	17.52	6.2	5.8	1.2∼2.7
Clay	12.0	0.25	19.22	70	16.9	5.9∼7.5
Powdery clay	11.3	0.25	19.22	40	15.5	4.8∼6.0
Strongly weathered mudstone	25.0	0.35	22.00	90	30	1.7∼2.6