What is the best way to define your various stripping layers on a corridor when it’s not all stacked on top of each other? If we have to strip topsoil on the left and right hand sides and mill in the center, is there a way to do that in the Define Strata menu, or is it best to use the corridor template to model it? It appears the Define Strata menu is best used only when everything will be stripped uniformly.
You could utilize the AOI in the take-off tab, you could create a stripped OG (it appears what is displayed is a hma demo with an og strip. You can build that surface and make it your OG in the design corridor. your OG to Strip would be your delta and all other volumes would be a excavation/embank or section. you could create a material layer for stripping in the corridor and have all of demo instructions reside under. Close out your corridor to the strip/demo material surface in the side slope instruction.
I find modeling it out in the corridor best. You might get some goofy numbers if it is all built in one corridor, I would think having a strip corr and a design corr might give more accurate numbers on the reporting side.
You will need to populate your MSE manager so that you can tell the instruction what material resides above - Topsoil - Milling - Topsoil.
Using a surface instruction like you are - i would use it (the surface) as the OG in the design Corridor and define the stripping in the AOI for your volume
I personally only use the strata when i am trying to quantify rock in excavation but we have good soils in this neck of the woods.
Brian
TBC Corridor Modeling is defined so that the following happens
Existing Process
- You have Existing Ground Surface
- You can apply a Topsoil Strip to remove material from the surface as a strip under the construction area in Fill situations
- You can apply strata using Boring Logs or using surface models that define materials that will be “Cut Into” by the corridor design
In the case where you have an Existing Road in which you want to mill out materials and you have the embankment areas where you want to strip topsoil or other materials then the only way you can do that in TBC is to take your existing surface and apply adjustments to those areas for Milling and for Topsoil and create “Strata Surfaces” that can be modeled by the Corridor Engine for volumes.
However if 100% of those layers have to be removed then the Corridor Model will not do that it will only remove the materials that are either Stripping (in Fill) or Strata that is being cut by the corridor design - unless you can build an Overex Surface and add to your Corridor Design model for the removal materials - in that situation you can have areas that are Overex (below all subgrades) and areas that would be excavated by the Design anyway (so not overex), so your Overex model has to a) account for the materials that have to be removed and b) the materials that need to be cut by the design model anyway. The Create Composite Surface command and Merge Surface Command can help with this merging of Surface models to create the surfaces that you need but it is not a trivial task for sure.
In your Existing Model - you will need breaklines that bound the different areas of excavation (Milling and Stripping etc. You can use the Apply Surface Site Improvement Command to apply Subgrade Adjustments to Existing Terrain (or you can do this with Demolition Site Improvements in the Takeoff Workflow), to remove the Milling to create a Milled Surface and the Topsoil to create a Topsoil Removed Surface. - you can then create a subgrade Surface for the Milled Surface and the Strip Surface and the Bottom of all Milling / Stripping using the Create Subgrade Surface Command (works for both Demolition method and Site Improvement Method.
The above surfaces can then be set up in Define Corridor Strata if required for the Corridor Earthworks Reports - however I will often just create the bottom of Milling and Stripping Surface and use that as My OG in the Corridor and compute those volumes for Milling and Topsoil using Volumes Manager or one of the TBC Volume Commands - if you want to use the Corridor to compute these - treat the Existing as Original and then add the Milling Surface and Topsoil Surfaces as surface instructions and assign materials above them (Topsoil or Millings) and that should run you sectional qtys for those materials. Then create a second corridor using the bottom of milling / topsoil as your OG and your corridor / corridor subgrade model as Finished Grade and that will get you the residual earthworks qtys as well as the Corridor Qtys.
OG - Milling = Milling Qty, OG - Topsoil = Topsoil Quantity