engineered cinder block walls

[peterjgibson]

Greetings! I've been searching the web to try to find how does one build a n engineered cinder block wall for a shop. Here is the confusion, I've never done it before. The county I live in wants me to start with 12" wide blocks for the first couple of layers, then use 8" block for the mid and top layers. How do I go about putting in rebar to make sure it will go through both blocks with the different width? Where can I find an illustration? Part of the wall will be 6 ' high and another section will be 8' high. It will be used as soil retaining and is also for a shop addition. I greatly appreciate any information, suggestions and ideas. Thanks Pete

[AndyS]

Andy comments

This could get tricky. The soil retaining wall will have a lot of horizontal pressure and may need the rebar and concrete filler. The shop wall will have mostly downward pressure and doesn't need to be as "solid". So it depends on how high the soild retaining wall is and whether the shop wall is being built on top of it........

If you put drainage pipe on the "soil side" and use gravel as backfill, there will be a lot less pressure, assuming you can find a place to run the drainage off to..... Also, the wall will probably leak, and may get

your shop wet.....

So, you see, your question can get complicated...

Here's an idea: Excavate about two feet back from the shop wall, and there put a second, lower wall for your soil retention. That till give you easier specs for each wall, and a place to store your lawnmower and pictures of your mother-in-law. Drainage will be easier, also, tho you might have a small moat after a rain, but, heck, you can stock it with fish......

Andy in Eureka, Texas

[Bob Morrison]

The simplest thing would be to have an engineer design the wall with the necessary details. Then the county will have very little to complain about.

[peterjgibson]

Thanks Bob. It actually is an engineered, county approved wall that is requiring me to start with the 12" wide and then going to 8" wide block towards the top. It will also be filled with cement and rebar. I not sure how to place the rebar or the placement of the 8" block on top of the 12" block at the trancition?

[peterjgibson]

Andy Thanks for the reply. I did forget to mention that this wall will have both rebar and be filled with cement as per county approved plans that were engineered. I'm assuming that they know about the pressures as you are and mentioned.

[Bob Morrison]

The engineer didn't give you details? He or she should have. There should be complete details showing required bar placement with dimensions at all locations. If you do not have this information then the wall has not been properly engineered and the county should not have approved the design.

Go back to the engineer and ask for more information. Did you pay this person?

[Glenn]

When I was younger, cinder block was used occasionally but at least around here, I haven't seen one for 50 years. Do they still make those poor quality things or is "cinder block" a regional euphemism for the concrete block of today?

[Glenn]

OT. I see dozens of mile long coal trains go through this area daily. That has to make a lot of ash, ie cinders. Yet I never see any.

I know most furnaces at the P & L's powder the coal and then burn it. Now I know there is no such thing as burning anything completely. even gas has an exhaust. Does the coal ash go up the flue?

[AndyS]

Glen, I read a post a couple weeks ago about this. Blocks in olden times were actually made from cinders. They weren't very strong. Today all blocks are concrete of some form. They are much better quality. However, the "cinder block" term is a holdover. I doubt you could buy a real cinder block anywhere.

Anyway, that's what I read.... somewhere.... maybe here ...

Andy in Eureka, Texas

[Glenn]

Careful with that "olden times" expression. I remember they very well and I ain't "that" old. :)

Actually they weren't too bad but needed to be used above ground. They were lighter by about 1/3. They were porous though and easy to break. You needed to lay them with gloves because they were hell on the hands as in sharp rough. They were used mostly for inside partitions. Came in modular 4" and 8" but I don't remember ever seeing 12" although they probably did.

The cinder block name slays me though, we just call them concrete blocks around here and I haven't heard the other term for many, many years so as I said, it must be regional. Kansas City area,

[DanG]

Yes. It is collected and marketed as fly ash. It is used as a substitute for lime in ground stabilization and is used as a pozolin in concrete manufacture taking the place of much of the Portland.

______________________________ Keep the whole world singing . . . . DanG (remove the sevens) [e-mail]

[Jonny]

Cinder block in my part of the woods comes in 16" and 8" wide blocks. The

16" version is essentially two 8" blocks combined. Other than width, remainder dimensions are approximately 8"X8" for both blocks.

Since am unaquainted with 12" cinder block, I cannot know the cavity dimensions or if there is more than one cavity and in standard 16" wide cinder block. Fill me in.