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Is there an easier way to do steps in a corridor model rather than inserting a template at every step IE, 14+97.40 another on at 14+97.45. Or adding breaklines on the corridor surface? I'm trying to build a Gabion basket wall with steps in it.

Kind of like this you mean?

I built the stepped base of the wall using an offset and delta Z table from the HAL and the trick on that is that for all the step locations you need both an Offset Table that calls out all the stations and a DZ Table that does the same - that way the corridor model will drop you cross sections at every start / end of step point. If you just put in a fixed offset of e.g. 12, then you will only get cross sections based on your corridor drop intervals eg every 25 - so your steps will not be sharp. In this case - I did not link the wall base to my HAL - I just created the Wall Base as a Node with no surface layer - that way it hangs in space on its own and then you can build out the Base of the wall or the face of the wall as Material Layers in the Template - in this case I put the base (Steps) in the Finished Grade layer and I put the Fale and Top of the wall in the Gabian Wall Layer - this also shows that you can create Layers "Above" Finished Grade as well as Below Finished Grade

If you want a Material above the Gabian Wall Base to the Gabian Wall Face then you need to create a 3rd surface called Gabian Wall Base, and then you can say that the BAse is part of Finish as well as part of Gabian Wall Base - and then because of that you can say that above Gabian Wall Base you have Rock Cage material (or similar) - that way you can compute all of the Gabian Wall Materials even though in this case I put them above Finished Grade.

My Station Offset Table looked like this for the base of the wall

0            12

100         12

100.01   12

200         12

200.01      12

300            12

300.01      12

400            12

400.01         12

500            12

My Station Elevation Table looked as follows (Note I copied and pasted the Rows from the table above so that I only had to enter the elevation details

0            0  

100         0

100.01   3

200         3

200.01      6

300            6

300.01      9

400            9

400.01         12

500            12

To build the top of the wall - I just used a Slope Elevation Table - and used a slope of Z6 to get the face angle of 6 degrees and a target elevation of 120 (fixed elevation top), however the Elevation could have been a Delta Elevation or actual elevation table to give a varying elevation along the top

You will see a slight kink in the wall face at each step because 6 degrees slope from the base before a step and 6 degrees from the top of the step after a step coming to the same target elevation is not the same place - if you want to discuss how to handle that - we can look at that - the delta is what 6 degrees represents at the step size (in my case of 3') which is ~ 0.31' - you could of course have a slope table that varies the 6 degrees to an adjusted value after the step to bring them into the same end location if you dont like the kinks in the wall face (or something like that)

Hope this answers the question and that I got what you were trying to achieve (at least in principal

One Template - just using slope tables and a couple of tricks ...

Alan

So I have been looking into this as a problem and have found out the following

1) When you drop in a reference template, no matter how close a template is to another template we force a drop of a "cross section" in the corridor model at each Template location which is why when you do that you get the vertical steps in the gabian wall base as you wanted. 

2) In Tables when you enter values into a table for Offset, Slope, ELevation, Delta Elevation, we have a tolerance of 0.1m or 0.34' between which we will not create a cross section drop at the table locations - that means where you have an Elevation Step as you had here, the table would need to look as follows for it to work

Station 0           Elevation  100

Station 23.61    Elevation   100

Station 23.94    Elevation    98 (Note >0.33 Station Gap)

Station 87.21    Elevation    98

Station 87.54    Elevation    96 (Note >0.33 Station Gap)

Station 120.56  Elevation    96

In this way you will get a cross section at your station points along the road eg every 25'and then you will also get section drops at all station points in the tables - giving you approximately what you were after - the step faces will not however be as close to vertical as you may have wanted.

I am not clear why we have this tolerance value as a limiter - however it is there and that is why you were seeing the sloping faces, because your Top of Face and Base of face points were too close together and therefore one was being skipped and you were connecting to the next location - whether that was a Table location or a corridor sample interval location (whichever came sooner).

I have also looked at the 2D line as a potential issue also - I converted that into a Station, Offset Elevation Table and added it as a Offset table in the Template, and it seemed to work fine - When it was defined as a 2D line it also worked fine - in the very first step there is a slight issue because there is an offset node in almost the exact same location as the step (there are a couple of points close together and that creates a minor issue in the step face, however all the other faces that I looked at came across ok (it seemed at least)

So it seems that the primary failing here was that table nodes were closer than the 0.1m / 0.33' tolerance that we allow in the template editor.

Let me know if this helps - The attached file is the Steps computed in this way as an example (I did not remodel the whole wall - but I think this shows how the Table needs to be constructed for this to work using Tables vs Templates.

Alan

So I continued to look into this today to try and work out why when you have a few instructions the surface fails to form correctly despite having the data now set up in what would appear to be the correct way.

Normally when you are building corridors the main alignment is curvilinear and all elements are tangential to each other. when you form the Corridor Surface model it actually makes the surface an Alignment Based surface and then it triangulates the surface based on Station and Offset methods vs the traditional near neighbour triangle sweep method - however in this model, the alignment contains many non tangent sections which causes the corridor surface model to abandon the Alignment Based Surface and therefore tries to triangulate using the radial sweep method (nearest neighbour) and this causes the wrong nodes in the surface to triangulate together forming an erroneous surface that doesnt expose the steps in the correct way.

We validate that this was in fact the problem by using the Alignment Editor - hold the CTRL key and click on the settings button of the ALignment Editor - and that shows the non tangent section s and deflection angles. By changing all of the non tangent sections to tangent sections, the model reformed and gave nice near vertical steps. (change the deflection angle to read dl0 or dr0 to set the deflection left or right to 000 00 00.00 degrees. This worked well, but onbly if the alignment does indeed have truly tangent sections of the HAl.

We now realised that when you drop a Template Reference - that forces a breakline into the corridor surface at the specific stations(s) where the Templates are dropped - this means that the downstream triangulation has to honor the breaklines whether the alignment is truly tangential or not. However when we define Tables, we are a) filtering (as explained previously) but also we do not drop a breakline into the model and therefore allow the Radial Sweep triangulation to form triangles incorrectly.

Development will look at this to see if we can address the above issues so that Tables will create drops where you define table data lines, and create breaklines to constrain the model correctly in these scenarios - this was a perfect storm eric - apologies but today your Template approach is the best method (Many Templates that reference the first temolate at the Top and Bottom of all steps. We will endeavour to resolve these isues to make this easier and less reliant on the size of offset used here.

Thanks for raising the issue 

Alan

Thanks for the response back and the explanation behind whats goes on. I totally understand now why its doing what its doing. I really appreciate it!