Importing HEC2 data for DAMBRK

Dear Maeder ,Chris,

I get your point but my problem is that the reach being subcritical and with important submergence effects close to the dam option 1 one gives insane discharges what is not true while option 13 gives real values so my problem has no solution, the reach has sugmergence effect that option 1 does not consider. Could you indicate to me how to define the breaching time, i.e for example I want the dam to fail 40 hours from start of simulation. truta

Thanks in advance
LUIS CARBALLADA



> Dear Carballada, Luis :

> You are correct. If you need a reservoir depletion table, then make certain you use Problem Specification Option 1. This is the only way to get this table.

> If you have any additional questions or need any further information, please contact me again.

> Sincerely,

> Chris E. Maeder
> Senior Technical Engineer
> chris.maeder@bossintl.com



> > The version of Dambk that I bought from you , the extended version when I use option 13 I found no way of getting the resevoir level evolution,because the graph they do not give depletion table for the option 13 is there a way to get resevoir level evolution

> > Best regards
> > LUIS CARBALLADA
> > Hydro-Quebec

Hy Ben:

I receive your call and I had called you to say that the only thing to change is here and pu us instead of french canadian so the hecras file is close at last.

One question I just bought DAMBRK the big version from you:

1) is there on your package the capability of importing HEC2 data for dambrk.

No, DAMBRK cross-sections are totally different than HEC-RAS and HEC-2. In DAMBRK they are entered as top-width and elevation, whereas in HEC-RAS and HEC-2 they are entered as station and elevation.

However, our RMS and RiverCAD programs can be used to cut cross-sections from digital topography and then you can use our software to measure the top-widths from the cut cross- sections. In addition, you can directly read in the DAMBRK results into RMS and RiverCAD and produce a flood inundation map.

2) here we have hydrographs with a very long time base it can last 2 month since computer time is not a problem, do you have the capabilities on your DAMBRK package if the simulation time is exhausted to continue the simulation from where it stops

You need to break up your 2 month hydrograph into pieces and model the time period as multiple runs. For example, 1 week long each.

Regards
LUIS CARBALLADA

Dear Luis Carballada :

Again, you are correct. Option 1 does not account for submergence effects. However, only Option 1 generates the reservoir depletion table.

To get the dam to fail 40 hours in the future, you must have steady state conditions, set the water surface elevation breach elevation equal to the initial water surface elevation, and then in the boundary conditions input screens, set the time to dam failure equal to 40 hours.

Here is what our on-line help says about this:

TIME TO DAM FAILURE
Time at which the dam begins to fail. In other words, this is the time when the time- step changes, from the initial time-step to TFH/MDT. See the section titled "Time-Step Selection" in Chapter 5 for more information. [36-TFI]

NOTE: This entry usually only needs to be specified if the "Water Surface Elevation at Time of Breach" entry and the "Initial Elevation of Reservoir Surface" entry in the Reservoir and Breach Description screen match and the user wants the dam to fail at a pre-determined time. See the section titled Time-Step Selection in Chapter 5 for more information.

If you have any additional questions or need any further information, please contact me directly.

Sincerely,

Chris E. Maeder
Senior Technical Engineer
chris.maeder@bossintl.com

Dear Chris Maeder:

On page 4-54 of the manual the values of spill discharge coefficient is given, but it is english unit, how does it work when using metric units

best regards
luis carballada
hydro-quebec

Dear Carballada, Luis :

You enter the spillway overflow discharge coefficient equal to the weir coefficient (between 2.6 and 3.0) times the spillway length in meters. So, the spillway overflow discharge coefficient is not the weir coefficient. DAMBRK uses it that way, and can switch units without problem.

If you have any additional questions or need any further information, please contact me again.

Sincerely,

Chris E. Maeder
Senior Technical Engineer
chris.maeder@bossintl.com



> Dear Chris Maeder
> Dambrk manual
> luis


>> Dear Carballada, Luis :
>>
>> Of which product?
>>
>> Sincerely,
>>
>> Chris E. Maeder
>> Senior Technical Engineer
>> chris.maeder@bossintl.com