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One Way or Two Way shear stress

One Way or Two Way shear stress

One Way or Two Way shear stress

Attached are the post results of shear stresses SQX and SQY of reinforced concrete tank with 36.33' of fill.

RE: One Way or Two Way shear stress

I can see the problem.

RE: One Way or Two Way shear stress

Do I choose slab thickness so it is below 120 psi for one way shear or below 240 psi for two way shear?

RE: One Way or Two Way shear stress

I'd have to see the tank and your results (you didn't include them). I can never keep straight those STAAD stresses. But i believe the one way shear number is the one you need.
But I do reinforced concrete tanks all the time. If you gave the dimensions of the tank, the liquid level and wall thicknesses, I could tell you if they're right.

RE: One Way or Two Way shear stress

Jed, Tank is 7.67 feet long x 4.57 feet wide x 9 feet high with no appreciative water inside.

RE: One Way or Two Way shear stress

wall is 8 inch thick and slabs are 12 inch thick

RE: One Way or Two Way shear stress

P.S. This is 1/4 of tank due to symmetry

RE: One Way or Two Way shear stress

For a tank that size 8 inch walls might work, but I'd recommend 12 inch walls for constructability.

RE: One Way or Two Way shear stress

The attached pdf shows SQX and SQY shear stress that are not continuous across the slabs like they are for box culverts with this much fill? I think this is closer to punch through stress versus one way stress?

RE: One Way or Two Way shear stress

Edward, I started responding to you because I thought it was funny that you said to look at an attached pdf, yet there was nothing attached. I felt kind of bad for teasing you, so I engaged with you.
But seriously, you need to learn how to attach your pdfs.

RE: One Way or Two Way shear stress

Jed, You are correct. It took me several 6 posts and I finally got the attachment on post 7 above. But the point of discussion from the shear stress models was from these models were they one way or two way (punch through) shear stress? I finally got an answer from Sye at Bentley that these 2 models are one way shear stress. This lrfd load factor value is about 129 psi for 5000 psi concrete. Edward1

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