[jadams]

In the past I have always had to manually input the data. I do however tabulate the data for each structure in Excel first and ctrl+C and ctrl+V it into RAS. I do this because usually you are flipping between GIS data, survey data, and the program to get stations and offsets and it can get confusing in a hurry. If there is a way to automate it I am interested as well.

[jadams]

I was able to get real stationing back on the project just by going to the Geometric Data->Tables->Names->River stations and assigning a value to the beginning section. After that I was better able to interpolate where my new data went and could create new sections at the appropriate stations.

[jadams]

Are you using a hotstart file for your initial conditions?

[jadams]

I just tried it with my data set and got the same error. I changed the output directory to a folder on my local machine (not on our server) and it worked fine.

[jadams]

Make sure the background processing is turned off. Under geoprocessing-Geoprocessing Options. Also I have found that if you are working on a server the program crashes often. You may want to try moving all your data locally on your machine and try it if the problem persists.

[jadams]

Easy rule of thumb is 1:1 ratio for expansion contraction. This is why i ensure field survey information at the culvert mouth and atleast the culvert width from each end.

[jadams]

I would do exactly that. You typically want a calibration model with the existing conditions anyway. After you have that save the geometry file as something else and manually edit the cross sections. This alteration shouldn’t effect your delineation because all you really want is the WS elevation anyway.

[jadams]

I notice that the error occurs near where your slope begins to increase. Have you confirmed that you aren’t going supercritical.

[jadams]

For unsteady modeling the more complex your model the more difficult it becomes to keep it stable. A model becomes unstable when calculation iterations yield an error greater than the allowable tolerances set in the program. The first thing I would recommend is performing a draw-down model to calculate your initial conditions. See: http://hecrasmodel.blogspot.com/2010/12/how-to-create-hotstart-file-in-hec-ras.html

[jadams]

Ensure the model and the GeoRAS are of the same units and ensure that the export/import options had station elevation data selected.

[jadams]

Your model is likely going into critical flow and the transition from subcritical to critical can often unbalance the model. You can attempt to add cross sections, modify mannings “n”, modify your time step and several other things to mitigate this effect. For time step use the rule of thumb of 20 times less than floodwave or the courant Condition. For spacing you may check the Samuels equation to give you an idea if you need to interpolate a few more.

[jadams]

Create a dummy cross section manually at any station. You do not have to populate the values just make it. Then immediately delete it. The program will ask if you want to update reach lengths.

[jadams]

Please specify the start date and time for your Flow data and temp data and the end time.
Also specify the start and stop date of your run.

[jadams]

Go back to ArcGIS. Select your TIN and Export Data. When you give it a new name you should have an option to save the TIN with either the native projection or the same projection as the View Display. Change it to the View display. Now try to import the TIN again with RAS.

[jadams]

I believe you can input an elevation-area table into RAS. If you are looking for a graphic for this I know it can be done in HEC-HMS to define a reservoir.

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