Demise of My Service Pit

[garyde]

Hi Dale. Were you planning to form the side walls or to use cinder block. I think if you clear out the pit & pour the floor of the pit, you coud then use cinderblock for the sidewalls. You may have already thought this thru so just a thought.

[dale farley]

Gary, I was originally planning to pour the floor then build a box form and place it in the pit and pour around it. I had the hole the exact size to allow 4 inches of concrete all the way around the form. That is going to be a little more difficult now. I am now thinking about building two walls; one to hold the dirt and the other for the concrete. All this is going to complicate my procedure for installing the rebar.

I haven't thought about using blocks. I am not sure that would be strong enough. Not sure it wouldn't either. I am open to any suggestions, since I have a while to wait until the ground dries out a little before I start digging again.

[Jon Wehrenberg]

The walls on my pit are poured concrete. Whatever you decide to do the only requirement is to make absolutely certain that you eliminate any possibility that there will be side loads on the walls so the pit does not collapse inward when the weight of the bus is near it.

There is likely a modest pressure on the floor when the bus is on the tires, but as soon as you place stands under the bus and support the weight on them the concentrated weight puts a much heavier load on a very small area of the floor. All those loads are vertical, which is good, and they remain vertical unless the floor thickness and the base beneath the floor is such that it fails to support the load.

My floor beneath the bus is 7" of reinforced concrete and beneath that is a generous base of 1" crushed stone. I know from the various jobs I have done that support stands and jacks can get placed as close as several inches from the pit. If there is any question about the concrete supporting that weight then there will be a need for substantial steel plates beneath the jacks or supports to spread the load.

[MangoMike]

Dale,

I can offer no advice, just support. Bummer.

I guess that's where the term "pit in my stomach" comes from.

Mike

[Denny]

Dale,

There are cement blocks made for retaining walls. I believe they are 10 and 12" blocks and have a recessed area on each side of the top of the block to place rebar in a horizontal position. I used them for a retaining wall when building my garage. I have at lease 6 feet of fill sand behind the wall and they have not move. I also put vertical rebar in and filled them with concrete since the area is on a slope and there is a concrete drive on top of the fill. Four years later there has been no movement.

Denny

[wrongagain]

dale,
not to be kicking you when you are down, but given what just happened, after you get this done whats is going to keep it from being your new service pond.
just a thought.

[dale farley]

I think I am going with the concrete block walls. Once the ground dries enough to remove the dirt, I will form and pour the pit floor then lay the block wall. That seems to be the most logical solution at this point. Thanks for everyone's input.

[garyde]

Hi Dale. 6"x12"or 8"x12" block will work. You should have #4 rebar minimum for verticle reinforcement, every block or 16" on center. L shaped so that it is part of your slab pour. If you speak to a supply house, they should be able to point you in the right direction as far as guidelines. There is a standard drawing for 3-4 ft. retaining walls which you should use as a guideline. I can e-mail one if you like.

[rmboies]

I think I am going with the concrete block walls. Once the ground dries enough to remove the dirt, I will form and pour the pit floor then lay the block wall. That seems to be the most logical solution at this point. Thanks for everyone's input.

Dale, sorry to see what happened to your pit after all that hard work! We use cinderblock alot here in the south. Two of my barns were built with cinderblock. In the stall areas, we built the walls with wire between the block, put re-bar in the top openings of the block,(which is a little tricky to do since the blocks are layed in an alternating design), and finally we poured concrete from the top to re-inforce the walls. The walls have never cracked and if one of the horses kicked them, I guarantee you they only did it one time before they learned the wall was certainly stronger then their 1k bodies Good luck!

Debi

[dale farley]

Gary, Send me the drawing. Thanks.