Without using 2D modeling, what’s the best way to calculate an existing roadway sheet flow profile (HGL along roadway) under different return period storms? Suppose the roadway has subsurface storm sewer as well as roadside drainage ditches. Thanks.
In HEC-RAS 2D modeling,will water get lost from 2D flow areas? or water will build up against an imaginary wall at 2D area boundaries (similar behavior happen at HEC-RAS 1D cross section limits)?
How do we set up flows from HMS (via HEC-DSS) for use in HEC-RAS? I am talking internal boundary conditions - there are two options in HEC-RAS, namely uniform flow and lateral flow.
If I have subbasin say "A" and the river in HEC-RAS runs through its center. Should I introduce A flow by HMS...
1. can anyone explain to me the difference among engineering fill, select fill, structural fill, and general fill?
2. And for a berm of a dry detention pond, what type of fill is appropriate and material type - sand, clay, silt, or in terms of PI?
3. For backfill of a storm sewer pipe under...
Any hydraulic design criteria on a relief bridge? like low chord setting, or relief bridge low chord EL. relationship with main channel bridge? Thanks.
What’s the purpose of developing the term of specific energy for open channel flow? I understand specific energy is a component of the total energy by not taking account of the vertical distance from vertical datum to channel bottom. But I don’t see any advantage of using it. If we use the...
How do I get exact bridge backwater height from HEC-RAS? I am trying to find such an data output directly from HEC-RAS model with the bridge coded in, but I couldn't - Did I miss something here?
I am thinking to run the model twice (with and without bridge) and read W.S. Elevation from the X-S...
In NEH 630.1604 Page 16-14, it reads that 'This constant(Peak Rate Factor) has been known to vary from about 600 in steep terrain to 300 in very flat, swampy country.” Recent studies have shown the peak rate factor has a much wider range: from below 100 to more than 600. The standard 484 DUH was...
Under Gamma unit hydrograph in HydroCAD, I notice that the Y-coordiante is defined as relative intensity. however, in NEH tables of Appendix 16B, the Y-coordinate is defined as q/q-peak.
thus, in NEH Appendix 16B, the maximum Y is 1.0 (at T=TP, or at dimensionless T=1.0) and in HydroCAD tables...
Suppose I have a square shape pasture subcatchment (2 square miles) and it currently drains to a ditch long its border. Now, I am taksed to relocate this ditch to the basin center.
Since the TOC will be decreased (probably not by exactly one half, but I am sure it will be decreased), so the...
Does anyone know where I can get such data, like 10-,25-,50-,100-yr return period significant wave height, wave periods and stillwater EL for coastal Texas? Thanks.
any good equation for estimating riprap size around pump station discharge basin apron? The discharge basin itself is concrete one, and from there the discharged water will be spilled out to riprap apron/chute.
I guesss I can not use the river bank revetment protection equation since there...
With lack of other data or field info, has anyone used the Samuels equation to estimate how long a backwater effect can have on a river, L,which is measured from point of disturbance upstream:
L=0.7*D/S; D is bankfull flow depth, S is energy slope or bed slope.
In order to correctly model or calculate bridge scour, do I need to consider the effect of underground (under riverbed) footing and piles?
I am using HEC-RAS to do my work, but it can only model the above ground part of the piers. Underground footing and piles are not even recorded in HEC-RAS...
