Storm Sewer under new building
Storm Sewer under new building
(OP)
I'm designing an industrial building expansion that will go over some existing storm sewer. Because of flow lines, I cannot route around the building. I was thinking of replacing the RCP pipe with steel (cast iron) and backfilling with cement stabalized sand to make sure it never moves.
Does anyone have any suggestions for putting storm sewer under a new building? It will be 24" ~ 150' long. Should I use some sort of restrained joint pipe?
Does anyone have any suggestions for putting storm sewer under a new building? It will be 24" ~ 150' long. Should I use some sort of restrained joint pipe?





RE: Storm Sewer under new building
RE: Storm Sewer under new building
RE: Storm Sewer under new building
RE: Storm Sewer under new building
If possible, allowance to be made to provide a covered trench within the building just in case the pipe needs to be replaced.
RE: Storm Sewer under new building
RE: Storm Sewer under new building
you should never place a new building over a pipe:
what if the pipe collapses in the future!
what if you need to maitain that pipe!
Dumb idea,
relocate the pipe!
RE: Storm Sewer under new building
RE: Storm Sewer under new building
Best solution is the use a pipe casing (sleeve)large enough to allow a new storm drain pipe to be jacked thru. This will allow for replacement in the future if the new portion should ever fail. If the building has grade beams or curtain walls, make sure the structural guys leave a large enough opening for the casing (Min. of 6" clear) and that they span the opening with the bldg loads.
RE: Storm Sewer under new building
The drain itself should be surrounded in a minimum of 150mm thick concrete, however it might be a good idea to allow a little movement via flexcell boards at each drain coupling, which breaks the concrete and allows a little flexibilty
RE: Storm Sewer under new building
Very good answers guys, especially the negative end of Mr.? waterflowsdownhill and the positive end in Mr.? bigot's crossing over discipline comments. It shows that sometimes all disclipines have to come together to solve a problem rationally. I liked the encasing comment of Mr.? WINhydro.
I belive that with this kind of starting comments you should be able to logically solve your problem. Make sure you talk to those structural and geotechnic guys also. This is not your everyday civil problem.
RE: Storm Sewer under new building
RE: Storm Sewer under new building
(1) Placing the pipe under a building is not optimal, but may be the lessor of all evils and most economical solution.
(2) The main considerations are leak proofing the pipe, replacing the pipe in the future and structual soundness. The commonly accepted solution is to sleeve the pipe, like in a "jack & bore" crossing. A 24" RCP pipe would propaply require a 36" mild steel sleeve because a minimum of 6" clearance around the bells is needed and a common standard size is usually cheapest. The sleeve prevents leaks under the building by moving them out side, usually 5' minimum beytound the footer, it also enables replacement of the carrier pipe and it usually is structually sound enough. You may want to check the loading at the footers and possible use a lintel over the pipe.
(3) Place the minimum size required by good design. Face it, storm water systems will always fail because a bigger than designed storm will sometimes occur. Just make sure that failure will not cause problematic flooding and remember that everywhere else will be flooded at the same time due to the downpour.
(4) Encasing the carrier pipe in concrete is not an optimum solution. It does not allow for pipe replacement and unless steel is used at all joints, it wil not prevet leakage. If any leakage should occur, the building will be endangered.
(5) If a larger pipe is needed in the future, then it will be "jack & bored"
Clifford H Laubstein
FL Certified PE #58662