Emergency exit from storm shelter

[Gitche Gumee Kid]

I want a second exit to my storm shelter . My plan is to attach a 60" culvert to the shelter which is a concrete block structure with a 12" reinforced poured concrete roof (below grade).

The top of the culvert will be approximately 24" below grade and day-light at a hill side.

My concern is the area of point of attachment for the culvert to the opening that will have to be cut into the block wall.The main concern if how to water proof where wall and culvert meet.

A potential separate problem would be possible frost heave action. Would the culvert have to be joined to the wall in a flexible manner?

I just purchased that mini excavator. A well maintained 2006 model( Takeuchi TB016 )

Many thanks to any back yard engineers out there.

GGK

 

[BHD]

where the culvert will attach, or am I visualizing this correctly, as you talk about the block wall which would place the culvert on the side of the cellar, and extend out past the edge of a hill, is that correct?

how deep is frost line?

I would think if the base of the culvert is below the frost line that will will not lift, now the exposed end most likely will not be below,

ideas for sealing
1. get some one who can do a rubber roof at the joint of the block and the culvert,
2. foam gap filler and foundation coating,
3. Ice and snow roof membrane flashed around the area,
4. foundation coating or roof patching tar, and tar paper pressed in to it, to flash it, (possible plastic sheet in sted of tar paper),
5. latex roof coating with foam gap filler (may be window or fiber glass screen) for reinforcement of joint area.


land scape so excess water flow away from the area,

 

[Gitche Gumee Kid]

where the culvert will attach, or am I visualizing this correctly, as you talk about the block wall which would place the culvert on the side of the cellar, and extend out past the edge of a hill, is that correct?

how deep is frost line?

I would think if the base of the culvert is below the frost line that will will not lift, now the exposed end most likely will not be below,

ideas for sealing
1. get some one who can do a rubber roof at the joint of the block and the culvert,
2. foam gap filler and foundation coating,
3. Ice and snow roof membrane flashed around the area,
4. foundation coating or roof patching tar, and tar paper pressed in to it, to flash it, (possible plastic sheet in sted of tar paper),
5. latex roof coating with foam gap filler (may be window or fiber glass screen) for reinforcement of joint area.


land scape so excess water flow away from the area,

<================================0====================================>

culvert will extend out 90 degrees to the wall.
Frost line 4 to 5 feet in depth.

GGK

 

[relaqbr]

View attachment 317452

I want a second exit to my storm shelter . My plan is to attach a 60" culvert to the shelter which is a concrete block
GGK

Been reading Robert Heinlein I see
That is how he built his bomb shelter.

Not much of an engineer, but it seems the junction with the wall will be at least for or five feet down. Not much frost heave at that depth is there?

As for waterproofing I don't think flashing will work. Depending on what the drainage is like I think you will need to seal it. Flashing would only work on water falling on it directly and then going on by. And you got the contraction of the metal vs concrete. Could you fashion a rudimentary Bulkhead out of plastic material and then seal it?

Probably a stupid idea but....

Good luck!

 

[mjncad]

Sealing the (metal I assume) culvert to the concrete wall will be a challenge. I also suggest you install that culvert on a bed of pea gravel or stone of some sort so the gravel can absorb ground movement. Actually I'd be tempted to surround the culvert in gravel, and line the trench with geotextile fabric before placing the gravel. The gravel will also help drain water away from the metal culvert; thereby keeping rust at bay longer than moisture holding dirt ever will. You might look at how concrete and fiberglass septic tanks are supposed to be installed regarding a gravel or stone bed. What are you going to do to keep wildlife from taking up residence in your culvert? I like the idea of a second entryway in case something happens to block the primary. You want this to be a shelter, not a tomb.

 

[Depmandog]

You should be able to contact the CMP manufacturer to purchase a connecting band specific for your application.

The connecting band will have matching corrugation angles on one side, and flat steel on the other. The connected band clamps around CMP, using a tar based sealant between the band and clamp. The other end is a smooth sleeve, that slides into a circular cut opening in your concrete shelter. Void spaces between the sleeve and concrete are grouted with hydraulic cement.

Over the outside of the connecting band /CMP joint & sleeve/ concrete penetration, a waterproofing membrane is installed.

The sleeve is also mechanically fastened to the concrete, using an appropriate epoxy based fastening system.

Once backfilled, assuming you are below the frostline, movement will be minor.

Think along the lines of storm sewers / storm water retention, concrete drop inlet boxes, etc. What you are proposing to do is done all the time. Do you have a precast plant close by? That's probably where I would start asking questions. I know they can get you set up.

 

[kiotiken]

Not sure I fully understand, but for waterproofing the junction, there's a product called Blueskin that will do it.

 

[relaqbr]

You should be able to contact the CMP manufacturer to purchase a connecting band specific for your application.
....1
Once backfilled, assuming you are below the frostline, movement will be minor.
....2
Think along the lines of storm sewers / storm water retention, concrete drop inlet boxes, etc. What you are proposing to do is done all the time. Do you have a precast plant close by? That's probably where I would start asking questions. I know they can get you set up.

I deal with pond leaks every day. Concrete, membrane, etc, a lot depends on how well it is installed but I have seen very few products and materials that will stay waterproof in 10 years. I doubt seriously that any of the storm drains and such mentioned would be impervious to water and not leaking it's just that they don't leak much and are usually in locations where it doesn't matter. I assume you do not want your storm shelter filling up with water after it rains And of course it will be back filled so do you really want to be digging it up in 7 years?

That said, if the hole in your concrete wall was grouted smooth and had pretty close tolerance to the cmp-- Corrugated metal pipe you could pack the junction with something like Henry's

 

[GLyford]

Do you have enough height that your culvert can slope down towards the "daylight" end some? If you have more than enough, maybe even a perforated drain tile running just under the culvert out to daylight would at least keep the joint area from sitting in water...

 

[Gitche Gumee Kid]

Do you have enough height that your culvert can slope down towards the "daylight" end some? If you have more than enough, maybe even a perforated drain tile running just under the culvert out to daylight would at least keep the joint area from sitting in water...

Yes. I have enuf for your sugestion. Thanks ,everyone. Drain tiles will go under the 60" pipe in abed of pea gravel .

The Blueskin product looks interesting.

GGK