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# RS2 Tunnel Design Import

## 1.0 Introduction

This tutorial shows how to import an RS2 tunnel design into RS3. The import feature allows users to create a 3D tunnel from a cross-section tunnel. The tutorial uses an RS2 example file that has a sequence tunnel excavation with bolts applied at each phase of construction. We will create the tunnel from new file. The final model can be found in following tutorial folder with Tunnel Designer - Import RS2.rs3.

## 2.0 Tunnel Design

### 2.1 IMPORT RS2 PROJECT

First, we will import the RS2 project.

Select: File > Import > Import RS2 Property File.

Open the mingtan powerhouse design.fez file in the RS2 import tunnel design tutorial folder.

Make sure to import all properties, including material properties and bolt properties, as shown above.

Click OK.

### 2.2 CREATE EXTERNAL GEOMETRY

Now will create external geometry for soil domain.

Select: Geometry > Create external box.

Select Define By: 2 Corners.

For First Corner enter (x,y,z) = (-150, -50, 145)

For Second Corner enter (x,y,z) = (-180, 50, -90).

It should look as the following.

Select OK after entering the values.

Assign the soil geometry to sandstone material by selecting the external volume in properties pane in visibility tree and assign Sandstone as shown below.

### 2.3 FIELD STRESS CONDITIONS

We will now define the field stress conditions of the model.

Uncheck the Use actual ground surface check box. Then, change the ground surface elevation to 145 meters.

Select OK.

### 2.4 TUNNEL DESIGNER

Part A: Left tunnel.

Now we will import the cross-section design from RS2 to RS3 tunnel designer.

First, select Tunnels > Tunnel Designer.

On the right side of the menu, select I/O and select Import.

We will first import RightMingtanPowerhouse.dxf. Select OK and you will see the geometry imported as shown below.

Change the tunnel name to ‘right’ to indicate this geometry will applied to the right side of the soil geometry.

#### 2.4.1 Extrude

Select Path.

Under Path options, select Extrude, and enter 20 meters. Press apply to see the extrusion of the model as shown below.

#### 2.4.2 Supports (Bolts)

Now we will create bolt support around the excavation. Select the Add supports button on the top. You will see the supports menu. Under the … dropdown menu, select Add Bolt Perimeter.

Under the details section, select the Define button beside location. This is used to define the sections where bolts will be applied. You can select the left corner of the tunnel, top curved line, and right corner as shown. Tunnel designer will apply the bolts around the selected sections of the tunnel. Right click and select done after selecting the vertices.

Change the Bolt Length to 8 meters, Spacing Along Path to 2 meters, and Orthogonal to Path to 2 meters.

#### 2.4.3 Excavations

Now select Excavations. Under region 1, we want to apply sequenced excavation with Sequence In of 20 meters section every 1 stage(s) after excavation of the tunnel. Select the Excavation sequence and enter the following information. Make sure to press Apply after these inputs.

Now we will assign Region 0 sequence. Settings are the same as Region 1 except Region 0 has Stage Offset value of 1 stage as shown below. Select Apply.

Now move to Region 2. Like Region 0, the only difference is that Stage Offset for this region is 2. Select Apply.

Make sure lastly to go back to Bolts and assign the bolt properties to Default under bolt property dropdown menu as shown below.

Lastly we will add the last portion of the bolt on right side of the tunnel. Select Add Bolt perimeter under Supports and select … option.

Assign bolt properties to default. Select the location and select the two vertices at the right corner as shown below. Change the Bolt Length to 8 meters, Spacing Along Path to 2 meters and Orthogonal Path to 2.5 meters. The dialog should look as below:

We are finished with the right side of the tunnel. Now we will import the left portion of the excavation.

#### 2.4.4 Part B: Left tunnel.

The procedure is similar to right tunnel. We will be guiding you through the steps, but we want to encourage you to follow the text and see if you can create the tunnel with steps provided for Part A. Images will be provided for reference at the end of each main steps.

1. Import dxf. Select I/O and now import LeftMingtanPowerhouse.dxf.
2. Extrude the tunnel to 20 meters by selecting the Extrude Path and entering 20 meters. Press Enter.
4. Change the bolt property to default by selecting Bolt properties > Default.
5. Add bolt perimeter around the sides and top of the excavation by selecting the left corner, top, and right corner of the excavation. Select Define under locations and select the following vertices. Right click and select done after selecting the vertices.
6. Change the Bolt Length to 8 meters, Spacing Along Path to 2 meters, and Orthogonal to Path to 2 meters.
7. Select Region 6 under Excavations and set sequence excavation with Sequence In of 20 m section and every to 1 stage. Select Apply. (Always make sure to apply after excavation inputs are entered).
8. The setting stays the same except for offset stages.
Select Region 4, Stage Offset should be 1 stage(s).
Select Region 7, Stage Offset should be 1 stage(s).
9. Copy the Region 4 setting by selecting … button, and copy. Now paste it to region 5. Change the offset stage to now 2.

Paste the setting to rest of the regions and only change the stage offset for following values.

Region 3: Stage Offset = 3.
Region 0: Stage Offset = 4.

Region 1: Stage Offset = 5.

Region 2: Stage Offset = 6.

Now we are done with designing the tunnel.

### 2.5 ADD TUNNEL TO THE MODEL

Keep the default values in Location as (43.08, 0, 28.76) and select OK.

You will get the prompt message with Constrained divide all. Select OK. You will see the tunnel applied as shown.

Now we will add the left tunnel. Select Tunnels > Add Tunnel. Under the based on option, select Left and keep the location as is. Select OK.

You can see the applied bolts and staged excavation as you shift along the stages.

At stage 1,

Stage 7 when all bolts are applied:

### 2.6 CONSTRAINED DIVIDE ALL

Now we will incorporate the tunnel to external geometry by using this feature. Select Tunnels > Constrained divide all. Keep the option to default and select OK.

## 3.0 Restraints

Select the restraints workflow tab. Select: restraints > Auto restraint (underground).

## 4.0 Mesh

Select the mesh workflow tab. Select Mesh > Mesh.

## 5.0 Compute

Select the compute workflow tab. Select Compute.

## 6.0 Results

Select results workflow tab. Select: Interpret > Show excavation contour. To focus on excavation contour, set the external geometry visibility off in visibility tree by selecting the eye icon. First we will look at total displacement by selecting Solids > total displacement in contour option.

At stage 1:

At Stage 7:

The displacement of excavation at the left side is significantly higher as there is more volume of soil excavated. Both excavations show high displacement occurring at the top and bottom of the excavation. We can also view the forces at the bolts to see what is happening at the supports. Select Bolts for contour type, and select Axial force for forces at the bolts as shown.

We can also see the total displacement of the bolts by changing the data type to bolt total displacement as shown below.

There are more options for visualizing the results so you can see what is happening across the stages at the specific elements of interest.

This concludes the tutorial.