地下建筑结构课程设计隧道衬砌设计(英文)

Underground Structure Course Designing

A Design of Shield Tunnel Lining College Civil Engineering

Major Department of Geotechnical Engineering Student No.100xxx

Name xxx

Director xxx

Date6th Sep. 2013

Part One: Design Data

1 Function of Tunnel

The planned tunnel is to be used as a subway tunnel.

2 Design Conditions

(1)Dimensions of Segment

Type of segment: RC , Flat type

Diameter of segmental lining: D 0=9500mm

Radius of centroid of segmental lining: R c =4550mm Width of segment: b=1200mm Thickness of segment: t=400mm (2)Ground Conditions Overburden: H=12.3m

Groundwater table: G.L.+0.6m =12.3+0.6=12.9m N Value: N=50

Unit weight of soil: γ=18kN/m 3

Submerged unit weight of soil: γ'=8kN/m 3 Angle of internal friction of soil: φ=30o Cohesion of soil: c =0 kN/m 2

Coefficient of reaction: k=50MN/m 3

Coefficient of lateral earth pressure: λ=0.4 Surcharge: P 0=39.7kN/m 2 Soil condition: Sandy (3)Materials

The grade of concrete: C30

Nominal strength: f ck =20.1N/mm 2

Allowable compressive strength: f c =14.3N/mm 2 Allowable tensile strength: f t =1.43N/mm 2 The type of steel bars: HRB335

Allowable strength: f y = f y ’= 300N/mm 2 Bolt:

Yield strength: f By =240N/mm 2 Shear strength: B τ=150N/mm 2

3 Design Method Requirement

(1)How to check member forces: ① Elastic equation method(option)

② Force method based on the textbook (must do this)

③ Bedded frame model(Beam element with elastic support)(option)

0P K =constant of rotation spring for positive moment at joint=18070/kN m rad ⋅ 0N K =constant of rotation spring for negative moment at joint=32100/kN m rad ⋅

(2)How to calculate reinforcement for segmental lining:Limit state method

①Based on the national code GB50010-2002 for reinforcement concrete design. ②Please choose the grade of concrete and the type of steel rebars.

Bolt: yield strength 2

240/By f MN m =

shear strength 2

150/B MN m τ=

Part Two: Computation by Force Method

1 Load Conditions

(1)Judgment of Tunnel Type (by Terzaghi’s formula) c 0⑤Average Self -weight Where

c γ= Unit weight of RC segment 326/kN m =

⑥Lateral Resistance Pressure Where

δ= Displacement of lining at tunnel spring η= Reduction factor of model rigidity = 0.8

E = Modulus of elasticity of segment = 423.010/N mm ⨯

I = Moment of inertia of area of segment =

3341

1.20.4 6.41012

m -⨯⨯=⨯ k = Coefficient of reaction = 360/MN m

ϕ= the angle of measured from the vertical direction around the tunnel

2 Computation of Member Forces

For loading case 4, For loading case 5, For loading case 6,

So the internal forces caused by surrounding pressures can be determined by accumulating the six loading cases, that is:

Where ,,pj pj pj M N Q are the bending moment, the axial force and the shear force (per unit length) under the j th loading case, respectively.

Then the total internal forces (i.e. the total bending moment, M, the total axial force, N, the total shear force, Q) per unit length (1.2m) along the lining can be obtained by the following equations: Where

And with MATLAB software, the maximum (positive and passive) moment, axial force, and shear force, which is shown in the Table 3. (The original code of MA TLAB can be seen in the addendum.)