x-section geometry – new item

[drainage321]

This is related to my previous post but taking it another step.

First Item:
I have entered in some bridge data and am now really questioning my approach on these x-sections. Please refer to the plan view attached exhibit. I can obviously end my roadway data at the point the x-section veers away from the actual roadway. Should I be revising these sections on the southeast bridge to parallel the roadway for a longer distance, then cross the roadway? my sections on the south side of the roadway will become extremely bunched together if i do this.

Second Item:
When I enter the bridge data in for the northwest structure, it puts a drastic jog in the bridge section related to the upstream and downstream sections. I’ve entered the bridge data in with the bridge design tool and also manually with distance and elevations with no luck. It looks fine in the plan view but not in the xyz perspective. The southeast bridge turned out just fine.

I’m considering breaking these two bridges into two separate projects so I can better accommodate the x-sections but what are the chances my water profile elevations are going to match up for the different storm events?

[Hydrojock]

drainage321,

1) It would be fine to end your bridge data mid-cross section. You might consider defining the crossing as a multiple opening in that case. The bridge section and a conveyance section out in the overbank. Cross sections bunching close together in the overbank is usually not a problem, so long as your downstream reach lengths are entered correctly.
2) I wouldn’t worry too much about how the x-y-z perspective plot draws. It’s a relatively crude rendering. Double check to make sure all your data is entered properly. The misalignment of the u/s and d/s bridge opening likely has to do with the zero station of the cross sections. Is you model geo-referenced? There could be a simple stationing error. Either way, the program is only 1-D so it doesn’t know the difference.
3) Breaking the model into two sections is fine. A little extra work, but if it makes it more conceptually ‘simple’ there’s certainly no harm in it.

regards,
James

[Author]

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