Tunnel Block Parameter

[Engr_Rod_D_Lecetivo_RMEE]

Hi, I am working on a Tunnel block I want with the specific condition. Wherein the middle wall is at equal length.
I am using parameter and action stretch. What I want is to maintain the wall thickness at the middle. I am trying to use fomula at parameter manager on block. But no can do. 
I was trying to work it out same as I work with Revit parameter by changing the expression. But it seems not possible. 

In a way that I can create a condition and relation with the 1 or more dimension as a formula expression.
Any taker, whom tried this approach.

I just want to figure out to make things simple. less error on manual operation.

Cheers,
Rod

[lim.wendy]

Hi Rod,

Thank you for your question about creating a Tunnel block with specific conditions using parameters and actions in Civil 3D.

Have you considered exploring the use of Subassembly Composer (SAC)? Back in 2015, I presented a class on using SAC to produce a Tunnel subassembly, which allowed for detailed control over dimensions and conditions. It might be worth exploring a similar approach for your current project.

We also have experts in SAC here on our forum who are more than willing to guide you. Please provide more details on your requirements.

[Engr_Rod_D_Lecetivo_RMEE]

In my current work scope this doesn't involve me creating the whole tunnel in Civil3D with the complex condition.
But you catch my interest. With this I am grateful. I am constantly Studying Composer. For now I can't apply it into my work. Because it isn't involved in me yet. 
Though, I this is necessary for me to learn and understand the concept of in relation to alignment. Probably a different topic but let me shot here.

What I am doing from Civil plan I check and create a block with parameter for the interference checking. This is very much time consuming right?
I now know that the Civil3D since 2015 have already the Composer according to you.

I am recently working in railway project last 2012. Previously I was in the Piping Industrial and Environmental Design.

My work involve alignments and other railway discipline in relation to alignment such as walkway, rail profile etc.

I would like to know with your expertise. Does having a composer will be convenient and efficient? 
In a way when the alignment is change in the Civil3D the other component that is attached in relation to the alignment also align automatically. Example of which is the Emergency Walkway.

What if I want to add a Electrical Post  also in relation with alignment with a certain condition?
I have also research that we can input sleepers auto. But I haven't yet figure how to. At the same the the turnout feature into my own configuration.

Other concerns involves, What if I want to add condition if I need to add post with this criteria specify such as in revit Parameter or so. 
I believe so, I have so many questions what Autodesk Civil3D approach in this such situation and how do you deal on its automation.
It will be helpful on my end if I have you guys to support me with my current problem.

Does the replace assembly apply with, example in Revit Family. We can replace family in the project with the same categories. Therefore, does this features apply also in Civil3D or we do have different condition to consider. Those are the things I need to know.

Because even if it is the same Autodesk product. Some features don't have the same configuration as per developers have different approach in dealing within it.

Cheers,
Rod