Trimble Business Center

Hello!

I am somewhat new to Trimble Business Center and need some help figuring out how to calculate earthwork volumes for payment per the requirements of my contract. I have the Survey Advanced Edition of TBC.

In essence, my project is a giant drainage channel. My project file contains three surfaces: an existing ground surface, a final excavated surface, and what we call a "template" surface that defines the limits for payment. Payment is not provided for any material that was not excavated and remains in place above the template surface. Payment is also not provided for any additional material excavated below the template surface. Below is a visual depiction of these limits.

I need to determine the earthwork volume that is below the existing ground, above the template surface when the final excavated surface is lower than the template surface, and above the final excavated surface when the template surface is lower than the final excavated surface.

I have gotten as far as creating my surfaces and generating a corridor. However, it looks like I can only get the program to calculate volumes based on only two out the three surfaces at any given time.

I have considered generating multiple earthwork reports to calculate the cuts and fills between the different surfaces, and then adding and subtracting the different cuts and fills to get the volume I need. However, I believe my client is expecting a single earthwork report as backup for the payment quantity. I also need to submit a PDF of the cross sections showing a visual depiction of the area excavated.

Appreciate the help in advance.

Are you working for Florida DOT by chance?

I have posted a response to this exact diagram sometime ago in the past. 

If you want to know your Pay Qtys only - then you can use Merge Surfaces - and Merge your WIP and FG surface and use the Highest surface - that way where you have underexcavated you will keep that data and where you have over excavated you will keep the FG surface - that composite surface you can use with OG to create your pay qtys in a corridor model - you add the OG as Original Ground and then add a surface instruction using the Merged Surface as your Finished Design and that will give you your Cut and Fill Actuals

There is a project underway currently that will allow Surface to Surface volumes between 3 surfaces. In the Corridor Model as you have found you can only have one Existing Ground and one Finished Grade and then you can have subgrades - but you cannot have what I would call a Work In Progress (which is what you are really asking for here. In Takeoff you can have an Existing, a Finished Grade, Subgrades, Soil Strips and an Overexcavation but again - no Work In Progress. 

I have requested this ability in the Corridor and Takeoffs so that we could do a Work In Progress - but the project ongoing to give you this will hopefully be in the next 0.1 release of the software for Takeoff / Surfaces - however for corridors you have to run this as two computations - OG - FG (Planned Volumes) and OG - WIP (Actual Volumes) and FG - WIP (Over and Under Excavation Qtys) and then you would need to merge the files in Excel and then do some column calcs to get the numbers that you want by End Section areas. If you report on the same stations the process is not too arduous, but agree that it could be easier.

You have to remove the Overexcavation Qtys from the Actuals and also remove the Underexcavation quantities (because that is work you still have to do)

You can show the WIP surfaces in the corridor model

If you have a sample of data where you have the 3 models and are happy to share it - I can play with some ideas to see what is possible beyond what I have told you here.

You can call me on +1 720 323 0481 if you want to discuss it at all.

Alan