HEC-RAS Data Input Format (River Flow and Sediment Transport)

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HEC-RAS Data Input Format (River Flow and Sediment Transport)

jmrsalonga
Greetings, everyone! :)

I am currently taking Water Resources Management for BS Civil Engineering program, and we are taught to use HEC-RAS to run river flow simulations for various river set-ups and characteristics (steady, unsteady, etc). The software is pretty much straightforward and I am having fun learning how to use all of its tools.

However, one tricky part is analyzing data inputs. Our professor gave us some clear instructions for the first few river flow problems, but I am clueless about this latest one. I assume this one is taken out of some file type that the software can read directly. Unfortunately, this is all I have and I just need to know what the symbols and numbers mean. Can someone here help me out to identify what these figures mean?

River Flow and Sediment Transport Problem with HEC-RAS

Cross Section Data

X1   M6.0       8     100     145    5280    5280    5280
GR    33       0      15      10      13     100       3     105       3     140
GR    13     145      15     240      33     250
*
X1   M5.0       8     100     145    5280    5280    5280
GR  32.5       0    14.5      10    12.5     100     2.5     105     2.5     140
GR  12.5     145    14.5     240    32.5     250
*
X1   M4.0       8     100     145   5280      5280    5280
GR    32       0      14      10      12     100       2     105       2     140
GR    12     145      14     240      32     250
*
X1   M2.0       8     100     145    10560    10560    10560
GR    30       0      12      10      10     100       0     105       0     140
GR    10     145      12     240      30     250
*
X1   M1.0       8     100     145    5280    5280    5280
GR  29.5       0    11.5      10     9.5     100      0.5     105      0.5     140
GR   9.5     145    11.5     240    29.5     250
*
X1   M0.0       8     100     145   10560   10560   10560
HY  R4 RM 0.0
GR    28.       0      10.     10      8.0     100       -1.0     105      -1.0     140
GR    8,0     145      10.     240      28.     250
*
*  Last cross section copy from previous section with elevations lowered 2.0 feet.
X1 MD.0
*

Manning’s n:  Main Channel = 0.03, Floodplains = 0.08


Use Toffaleti’s Transport Equation
Materials Transported: FS, MS, CS, VCS, VFG, FG, MG, CG
                                       2    3      4      5       6      7     8      9

Sediment Discharge Rating Curve (Qs= tons per day, Q=cfs)
 [applied to both U/S of RCH1 and RCH3]
  Q     100     1000     10000   100000
  Qs:
  FS   2.75     218.75   32160   181250
  MS   2.8     198.75   22160   101250
  CS   2.6     78.75   10160   151250
  VCS   2.568   56.75   6160     91250
  VFG   0.55     4.7     47       500
  FG   0.25     2.2     20       210
  MG   0.15     3.5     78       2200
  CG   0.15     3.5     78       2200

Bed Material Gradation
        FS MS CS VCS VFG FG MG CG      XSs
RCH1 10 20 20 20 14 8 5 3          1-2
RCH2 13 32 30 12 7 4 0 2           3
RCH3 18 23 14 13 14 10 8 0           4-5
RCH4 10 20 20 20 17 8 5 0           6-7


U/S  Inflow:    5000, 15000, 4500 cfs for period  for first 720 ,then 1440 and finally 1440 hours

D/S Water Surface: Assume uniform flow with reasonable friction slope based on Manning’s BC






For the second part, I already distinguished the FS, MS, CS, and VCS as the soil texture classifications, but I have no idea what the other numbers mean.

I'd really appreciate anyone who can guide me out here. Once I know what these values stand for, I can easily proceed with running the simulation. Thank you so much in advance, and I hope to learn more about the experts from here! :)
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Re: HEC-RAS Data Input Format (River Flow and Sediment Transport)

jarvus
That looks like a HEC6 text file.  HEC6 is an old sediment transport program that was replaced by HECRAS.

I'm a little surprised your instructor is trying to make you deal with that.  You might see if you can find a HEC6 manual online somewhere.

*
X1   M5.0       8     100     145    5280    5280    5280
GR  32.5       0    14.5      10    12.5     100     2.5     105     2.5     140
GR  12.5     145    14.5     240    32.5     250
*

The 'X1' stands for cross section.  So that is cross section M5.0.  I don't know what the '8' is.  The '100' and '145' are probably left and right channel station.  The 5280 are the lengths of the overbank and the channel.  The next two lines are the station/elevation data for the cross section.


Sediment Discharge Rating Curve (Qs= tons per day, Q=cfs)
 [applied to both U/S of RCH1 and RCH3]
  Q     100     1000     10000   100000
  Qs:
  FS   2.75     218.75   32160   181250
  MS   2.8     198.75   22160   101250
  CS   2.6     78.75   10160   151250


This looks like the upstream sediment boundary.  So, for instance, if the flow was '1000' cfs there would be 218.75 tons/day of Fine Sand.

Good luck.