Tunnel water conveyance The names of God subject of presentation : Modeling of twain Tunnel water conveyance Presented By : Hamed Zarei PLAXIS version 8 Tutorial manual Dynamics manual

To create the geometry model and steps of Tunnel modeling in PLAXIS , follow these steps: Geometry of a tunnel Material properties Boundary conditions Mesh generation Initial conditions Calculations Viewing output results

CREATING A GEOMETRY MODEL The creation of a geometry model is based on the input of points and lines. This is done by means of a mouse pointer in the draw area.

creation of a horseshoe-shaped tunnel Created the tunnel creation of a horseshoe-shaped tunnel The tunnel considered has a diameter of 5.3 m Space between tunnels is 12m Tunnel designer with current tunnel model

Static Analysis Static Modeling Boundary Conditions Click on the Standard fixities button to apply the appropriate boundary conditions. In addition to the standard displacement fixities

Material properties Static Modeling After the input of boundary conditions, the material properties of the Rock clusters and other geometry objects are entered in data sets. The creation of material data sets is generally done after the input of boundary conditions. Before the mesh is generated, all material data sets should have been defined and all clusters and structures must have an appropriate data set assigned to them.

Static Modeling Material properties 𝜇 E 𝜑 C γ )Degree( 0/23 5 x 10 5 ( 𝐾𝑁 𝑚 2 ) 𝜑 )Degree( C γ ( 𝐾𝑁 𝑚 3 ) 0/23 5 x 10 5 43 700 30 Material properties of Rock in the tunnel project

Static Modeling The properties for those Shotcrete are listed in Table Material properties Static Modeling The properties for those Shotcrete are listed in Table 𝜇 𝑊 ( 𝐾𝑁 𝑚 𝑚 ) 𝐸 𝐼 ( 𝐾𝑁 𝑚 2 𝑚 ) 𝐸 𝐴 ( 𝐾𝑁 𝑚 ) 0/2 2/3 1750 1/728 x 10 5 Material properties of the Shotcrete

Static Modeling Material properties 𝐸 𝐴 ∅ 1/2x 10 6 25 (𝑚𝑚) 𝐸 𝐴 ( 𝐾𝑁 𝑚 ) 25 1/2x 10 6 Material properties of the Rock bolt

Static Modeling Mesh generation In this example the 15-node element is used as the basic element type.

Mesh generation Static Modeling The global coarseness parameter can remain at its default value (Fine). It can be expected that stress concentrations occur around the tunnel. Therefore the mesh should be refined in these areas.

Static Modeling Select a Plastic calculation using Staged construction CALCULATIONS Static Modeling Select a Plastic calculation using Staged construction The first calculation phase is used to excavate the right tunnel and activate Shotcrete The second calculation phase is used to excavate the left tunnel and activate Shotcrete The second calculation phase is a plastic calculation, Staged construction.

Static Modeling Select some characteristic points for load-displacement curves Start the calculations

Dynamic Analysis Dynamic Modeling Standard earthquake boundaries are used at the bottom and at the right hand boundary to avoid spurious reflections

The earthquake is modelled by imposing a prescribed displacement at the bottom boundary. Dynamic Modeling Therefore the input value of the horizontal prescribed displacements is set to 0.01 m. The vertical component of the prescribed displacement is kept zero (ux=0.01m and uy=0.00m).

Dynamic Modeling Change the Rayleigh damping parameters α and β to 0.001 and 0.01 respectively

Dynamic Modeling Select Dynamic analysis for the calculation type in the General tab sheet. Set the Time interval to 0.5 sec in the loading input box

In this phase, a vertical harmonic load, with a frequency of 10 Hz and amplitude of 50 kN/m2 Dynamic Modeling

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