topic Re: UNRESPONSIVE [FEATURE LINES] STEPPED OFFSETS in Civil 3D Forum

UNRESPONSIVE [FEATURE LINES] STEPPED OFFSETS

christopher_c_donovan — Mon, 17 Jun 2019 16:53:20 GMT

Using Civil3D 2016 - I have been experiencing problems with Stepped Offsets from a Centre Line Alignment - odd levels on the stepped offsets. So I have made myself a very simple model - short alignment starting and finishing on the same Contour [87.00metres] - created a Design Profile to match starting and finishing at 87.00 metres. I then created a Feature Line dynamically linked to the Alignment and then created two Stepped Offsets from this linked Feature Line on 5 metres on eitherside of the Centre Line Alignment at a grade of -0.02% to the North [Downslope/Top of Page] and 0.02% to the South [Upslope/Bottom of page.

1] The Elevation Editor for each Stepped Feature Line shows that they are at exactly the same level as the Alignment Feature Line. A 5metre Stepped Offset at 2% should give an Elevation difference of 1 Metre. Whatever I am doing doesn't give such a result.

2] If I change the Profile of the Centre Line Alignment the levels on Stepped Feature Lines do not change. I understood this was the purpose of dynamically linking the Alignment Feature Line to the Alignment and that the Stepped Offsets would change with any change in the Linked Feature Line.

3] Finally if I create a Stepped Offset from the New Profile - the Stepped Offset Feature Line takes on the Elevations of the New Profile but does not take in the grade difference as with 1] above.

Any advice would be useful. I attach the relevant drawing.

Re: UNRESPONSIVE [FEATURE LINES] STEPPED OFFSETS

wfberry — Mon, 17 Jun 2019 20:10:52 GMT

I see no alignments or profiles in the drawing.

Bill

Re: UNRESPONSIVE [FEATURE LINES] STEPPED OFFSETS

Anonymous — Mon, 17 Jun 2019 22:05:10 GMT

A couple of comments and things to check.

First as noted, I didn't see anything as described in the attachment.

Second, stepped offsets are NOT dynamic. That is if the original feature line changes, the stepped offset will not change. It would have to be updated with "adjacent elevations by reference" tool.

Third, if you are using -0.02% that will be the grade which would be a negligible elevation difference. Stepped offset by grade would use 2%.

Thanks,

Re: UNRESPONSIVE [FEATURE LINES] STEPPED OFFSETS

Anonymous — Mon, 17 Jun 2019 22:26:14 GMT

Sorry, I should be a little clearer about what it looking for when it asking for as a percent. It is looking for the actual percent desired rather than a percent expressed as a decimal. In other words just use 2 rather than 0.02.

Thanks,

Re: UNRESPONSIVE [FEATURE LINES] STEPPED OFFSETS

christopher_c_donovan — Tue, 18 Jun 2019 10:51:21 GMT

That's odd - I attach the TESTBED.dwg again

The Alignment, Feature lines and Profile are down in the bottom Lefthand
corner -They are on layers:- 0-Alignment [Green] / 0-Featurelines[Magenta
] / 0-Profile[White.]

I have worked out the problem with the Elevations in the Elevation Editor -
I have been entering the grade wrong -inputting 0.02 for a grade of 2%
instead of 2!! Old Calculation habits die hard!!!

This leaves the question of the Stepped Offset FeatureLines not changing
when you vary the Profile of the CentreLine? Am I misinterpreting what is
meant by dynamically linked or missing out a step in the required Workflow?

Re: UNRESPONSIVE [FEATURE LINES] STEPPED OFFSETS

christopher_c_donovan — Tue, 18 Jun 2019 17:19:21 GMT

Thanks - Understood

Re: UNRESPONSIVE [FEATURE LINES] STEPPED OFFSETS

christopher_c_donovan — Tue, 18 Jun 2019 17:34:21 GMT

2% grade understood - still thinking in manual calculation mode!!

Can't get a handle on the ' Adjacent elevations by reference' idea - the
Dynamically Linked Feature Line will not allow the use of this Command if
you select it [The FL] as far as I can see which means I cannot 'Update'
the Stepped Offsets if I change the CentreLine Alignment Profile other than
by deleting the'old' Stepped Offsets and creating new ones from the changed
Dynamically Linked FL.

Am I correct in this?

Thanks