No flow rates are not known, only water depths. So if I understand correctly, I will design the culvert using standard HDS-5 procedure and assume there is no groundwater in the channel. Then I'll add additional freeboard equal to the groundwater depth in the channel?
The reviewing agency does not put restrictions on what software to use as long as I can provide readable results.
In my office, we use Bentley CivilStorm/SewerGems as well as HY-8.
I'm trying to design a culvert for a road that will cross an existing concrete storm drainage channel. The ground water table is above the channel bottom so groundwater is always present in the channel and occupies 20%~50% of the channel depth.
How do I approach this problem? How do I account...
So drainage should be provided through the wall using ground level weepholes or through wall scuppers?
And how would the sizing and spacing be determined. Do I use the standard sizing and spacing as if the wall was a retaining wall or would I treat the wall opening similar to roof opening and...
So I know that if I have a retaining wall, I have to provide proper drainage using weep holes or perforated pipes at the side with the higher fill to reduce the hydrostatic pressure acting against the wall.
But what if the grading is equal on both sides of the wall and there is no hydrostatic...
Thank you for your reply.
The recommended pipe was not GRE but FRP, specifically it used polyester resin, not an epoxy resin as in GRE.
Anyways after more digging around I think I did find the answer. The aggregate filler is added to the pipe in order to economically increase pipe wall...
Can anyone tell me the practical difference between RTR and RPM? I went through AWWA C950, AWWA M45 and ASTM D3262 and the only thing mentioned is that RPM contains aggregates while RTR does not.
So what advantage does one offer over the other? Are they suited for different applications or can...
A little late for this but my guess is that the designer is using a software like SewerCAD that calculates the HGL based on Gradually Varied Flow conditions. I've run under a similar problem while designing a storm sewer as discussed here:
http://www.eng-tips.com/viewthread.cfm?qid=403598
Refer to HEC-22 section 7.1.6 for information on energy losses.
Link
It seems that hydraflow calculates junction losses based on the "Approximate Method" (Sec 7.1.6.6) and does not account for benching.
Thank you beej67.
@psmart: Thank you. I will look into WinTR-20.
@cvg: Even if I'm designing a retention basin which should retain all the runoff, I still need the hydrograph to design an emergency spillway, or am I missing something?
Anyways if I want to size the basin using the...
Hello,
I'm designing a drainage system for a small industrial area consisting of a closed drainage system (pipes and catch basins) that will discharge into a retention (not detention) pond.
Right now I only have the IDF curves which can not be used to calculate the volume to be retained in the...
It's a 10-Year design storm. The model is for a car parking area with a patchwork drainage system that the contractor is trying to redirect using existing and proposed pipes since the original outfall is no longer usable.
Stormcad seems to calculate correctly using the traditional Rational Method and it DOES match the discharge I get from applying the rational method and Manning's equation manually. Stormcad presents the option to use the modified rational method but I did not choose that option.
Now my problem...
Hello all,
HEC-22 assumes that water is flowing under uniform flow conditions and the pipes are sized so that the pipe capacity is always larger than the incoming flow. On the other hand, computer software (such as stormcad) calculates using gradually varied flow conditions, and the water...
