Once the ‘Start of Span’ and ‘End of Span’ anchors have been added you can now add the mid-point anchor.
To the add the mid-point anchor, you first need to register the structure as the mid-point anchor location.
Navigate to the catenary wire that you want to anchor in ‘Wire Manager’ and click ‘Edit’ on the wire that you want to be the mid-point anchor.
This will display the ‘Wire Configure’ form.
Change the ‘Support’ to M.P.A.
When you have changed ‘Support’ to M.P.A, your equipment may deselect. Re-check the equipment box and add your equipment back onto the structure.
Click ‘Confirm’ to continue.
You now need to add the tie wire and anchor it to the structures either side of the mid-point.
To add the tie wire, you will need to create a new auxiliary wire by choosing the ‘Wire New Auxiliary’ button from the Linear Draft toolbar.
Choose ‘MPA Tie Wire’ from the drop down menu and then name your wire. Click ‘Confirm’.
Open the ‘Wire Manager’ and select the auxiliary wire that you have just created from the drop down menu.
Choose ‘Attach To Structure’ and select the structure that you wish the anchor the mid-point tie wire to. This will be the structure that you defined as the mid-point from the instructions on the previous page.
Confirm the height of the wire (same height as the messenger wire) and offset the distance so that it comes into contact with the catenary wire that it is anchoring (clamping equipment is not yet available). Click ‘Confirm’ to accept.
Once the tie wire is in place at the mid-point, it can now be anchored to the structures on either side.
Open the ‘Wire Manager’ and select the tie wire that you have already created.
Select ‘Attach To Structure’ and choose the structure that you want to anchor the Mid-Point tie wire to. Click ‘Confirm’.
The 'Wire Configure' form will now be displayed allowing you to choose the height of the wire (same height as the messenger wire).
Check the ‘Anchor’ and ‘Equipment’ boxes which will then allow you to add the anchoring equipment.
Click ‘Add’ in the Bracket column to add the anchoring equipment.
Depending upon your model specifications, you will need to choose whether it is a front or back anchor that is required. Make your selection and then click ‘Confirm’.
‘Front’ is determined from looking at the structure in a forward facing cross sectional view and ‘Back’ is the reverse side.
Once you have confirmed the anchoring equipment, you can double check your selection before clicking ‘Confirm’ to place the anchor and wire in your model.
Now following these steps again to attach and anchor the tie wire to the next structure along from the mid-point anchor.
Your complete 2D view of the Mid-Point Anchor will now look like the example below.