1940's Rebar Dwg. Call-Outs? 1

[justhumm]

I've run into this before, so I should know it, but I'm drawing a blank...

For a 1940's retaining wall drawing, some of the bars are called out as 3/4" diameter (phi), for example.

And some of the bars are called out as 1/2" "square".

In 1940, were they still using actual square bars? If so, would they have likely been twisted?

Thanks!

 

[JAE]

Every square bar I've ever seen has been twisted.
So yes - the "phi" is a diameter symbol for a round deformed bar. The small square is the size of the twisted square bar.

 

[robyengIT]

hope it can help

 

[msquared48]

I agree with the above.

I have a section of twisted square bar I use as a paperweight to remind me of my former days.

I have reformed since then.

Mike McCann, PE, SE (WA, HI)

 

[DLBridge]

I have reformed deformed since then

Sorry couldn't help myself...

 

[msquared48]

I sit corrected... speechless...

Mike McCann, PE, SE (WA, HI)

 

[DLBridge]

Sorry, very poor attempt at "deformed" reinforcement humor on my part. Now that I re-read that, it comes off as rather insulting.

I'll leave the puns to the professionals and stick to engineering.

 

[Ingenuity]

Every square bar I've ever seen has been twisted.

For larger size square bar, my experience is that they are NOT twisted. For example, I removed 1" square bar from a 1930's era building and was deformed but not twisted.

 

[JAE]

Ingenuity - interesting but makes sense as those larger bars might be more difficult to permanently twist.

 

[bridgebuster]

Ditto what Ingenuity said. I have a piece of square bar at home that is deformed but not twisted.

 

[fel3]

In the 1980s I was the inspector for a pipeline project in western Los Angeles County. A small portion of the pipeline alignment was in a two-lane road that had once been Highway 101 before the adjacent freeway was built. About two feet below the asphalt pavement, the contractor encountered the 9-inch-thick concrete pavement that had been the original state highway. My project manager had told me that the old highway was built in the 1920s. The contractor's task was to remove a 300-foot-long section for the pipeline trench.* The demo'ed concrete included 1/2" square bars on 12" centers. The bars were straight, not twisted, and were not deformed.

* This was one of the few times I felt sorry for a contractor: Immediately after finding the old concrete pavement, the contractor told me this was a changed condition and he would be submitting a change order request. But, I knew about the concrete beforehand because of a note in that particular plan & profile sheet. And, the note was BIG, consisting of 3/8" high lettering surrounded by a thick border. So, I asked the contractor to get out his plan set. He had highlighted everything significant in the plans using four or five different colors according to some system he had to organize the information. But, the note was so big, he had missed it (seriously) and it wasn't highlighted. Needless to say, he was VERY upset with himself. He didn't seem to be a "Game Player," so I think it was an honest mistake on his part and not some long game to get a change order.

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"Is it the only lesson of history that mankind is unteachable?"
--Winston S. Churchill