INCREASED "n" FACTOR TO REDUCE VELOCITY??
INCREASED "n" FACTOR TO REDUCE VELOCITY??
(OP)
I have an open channel between 2 fixed elevation RCB's. To connect these two I can use a drop structure or a slope of 1.33% which produces high velocities. Has anyone roughened the interior of an RCB, sandblast or water pressure on setting concrete to obtain a higner "n" value?
Would have to go from the normal value of 0.013-0.014 to 0.025 to reduce the velocities to a workable limit.
i would prefer not construction dragon teeth or blocks within the RCB because of possible trash hangup, maintenance is poor.
Anybody tried this?
Would have to go from the normal value of 0.013-0.014 to 0.025 to reduce the velocities to a workable limit.
i would prefer not construction dragon teeth or blocks within the RCB because of possible trash hangup, maintenance is poor.
Anybody tried this?





RE: INCREASED "n" FACTOR TO REDUCE VELOCITY??
RE: INCREASED "n" FACTOR TO REDUCE VELOCITY??
RE: INCREASED "n" FACTOR TO REDUCE VELOCITY??
RE: INCREASED "n" FACTOR TO REDUCE VELOCITY??
I was curious if anyone had tried anything but baffle blocks as per HY8.
Thanks for the replys.
RE: INCREASED "n" FACTOR TO REDUCE VELOCITY??
RE: INCREASED "n" FACTOR TO REDUCE VELOCITY??
What is the distance between the boxes? Can you riprap, grouted riprap or ? between the cbcs?
RE: INCREASED "n" FACTOR TO REDUCE VELOCITY??
gbam, have used the rip rap and grouted rip rap on other installations but owner wants to pave paradice and put in a parking lot, so RCB is required.
cah2oeng, have a problem at the exit, trying to keep the velocities as low as possible. May just have to buy adjacent area and put in an energy dissipator.
thanks
RE: INCREASED "n" FACTOR TO REDUCE VELOCITY??
RE: INCREASED "n" FACTOR TO REDUCE VELOCITY??
RE: INCREASED "n" FACTOR TO REDUCE VELOCITY??
RE: INCREASED "n" FACTOR TO REDUCE VELOCITY??
Cah2oeng---have done drops before and they would be applicable here, but the client doesnt want them.
gban--no problem with parking, want to put in a shallow RCB as much as possible for the economy, then a steep section(or drop) and then flatten out to the normal channel slope.
dicksewerrat--(love that moniker)no CGMP or internal rings allowed.
It looks like I'm going to end up with a broken back RCB with a CSU enegergy dissipator at the end.
Thanks for all your input, Tincan.