Dam and Spillway - Radial Gate Seal

[Everynameistaken]

Hi All,

This might not be the right section, however we are Structural and this problem falls on us for this project!

We are working on a project where a very old Dam and spillway requires the ogee concrete surface of the spillway to be repaired and replaced. Currently the radial gate that blocks the spillway is sealed at the base by the steel gate leaf being pressed into a small, poured in place lead block that is recessed into the surface of the concrete ogee spillway. When we upgrade this concrete surface we are looking for a way to potentially replace this old lead seal method with a new modern material.


We are having some trouble with the typical gate seal suppliers (who traditionally use rubber) to find an alternate detail that could bring the old detail into the current with modern materials.

Does anyone here have any experience with replacing old lead gate seals?

Without real alternate that is proven, may have to go back to the ":if it ain't broke don't fix it" and use the same detail!


Thanks

 

[DaveAtkins]

Why not use a rubber J seal or pork chop seal?

DaveAtkins

 

[GC_Hopi]

Have you consulted with a gate manufacturer or a seal manufacturer. It will depend on your design conditions.

 

[Everynameistaken]

Hi All,

Yes, we have spoken with many seal manufactures and they all say " we can build what ever you want" but very little idea on how to do a seal mounted in the concrete and not oin the gate itself.

The gates are very old and are in good condition and not being replaced as a part of the project, so if possible it would be great to have the seal replaced in the same manner as the original seal, which is cast into the base of the ogee. But this poses a different problem as having an rubber item that is in the spillway flow is not a great idea I don't think.

So we are looking to see if there is anyone out there who has replaced a lead block seal, cast into the sill with anything modern?

 

[GC_Hopi]

Why keep the old style of sealing? You can retrofit a J bulb on the gate and cast a plate in the ogee for the J bulb to seal against.

 

[GC_Hopi]

Here is a reference from Corps of Engineers ETL 1110-2-2105, "Design of Hydraulic Steel Structures", see the option C below. I have never used a rubber block seal so outside my wheelhouse.

 

[Everynameistaken]

Hi GC_Hopi,

Thanks very much for this!

The only reason we have not yet recommended the seal be applied to the gate, is that any gate steel work is not a part of the currently proposed project. They intent to re-coat in a coupl eyears time, so adding the steel scope of adding a seal changes their work flows.

We just wanted to know if there was a way to replace using a similar style that does not change the work flow. We have only ever used seals mounted to the gate as well.