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Bolted Tension Connections
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Limit State: Yield or Ultimate??
Yield: 36 ksi (strain = )
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Limit State: Yield or Ultimate??
12’ 24’
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Limit State: Yield or Ultimate??
P 12’ 322” long brace 24’
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mmmm….. Maybe we should not let it yield
P 12’ 322” long brace 24’
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mmmm….. Maybe we should not let it yield
P 12’ 322” long brace 24’
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If we limit the stress to less than yield, then….
P 12’ 322” long brace 24’
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If we limit the stress to less than yield, then….
P 12’ 322.4” long brace The brace would not extend more than 0.4” (do the math: eL = 0.4”) 24’
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If we limit the stress to less than yield, then….
P 12’ 322.4” long brace The brace would not extend more than 0.4” (do the math: eL = 0.4”) And the column would be leaning by no more Than 0.45” (do the math: Pythagoran 24’
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Then again…. Yield is no where near the maximum the steel can take.
P 12’ 322” long brace 24’
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Then again…. Yield is nowhere near the maximum stress the steel can take.
P 12’ 322” long brace 24’
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I mean…. Even if it yields at 36 ksi, it doesn’t break, right?
P 12’ 322” long brace 24’
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I mean…. Even if it yields at 36 ksi, it doesn’t break, right?
P 12’ 322” long brace 24’
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It seems like yielding is no big deal
P 12’ 322” long brace 24’
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It doesn’t break at 36 ksi (yield) Why not just say that 58 ksi (ultimate) is the limit??
P 12’ 322” long brace 24’
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It doesn’t break at 36 ksi (yield) Why not just say that 58 ksi (ultimate) is the limit??
P 12’ 322” long brace 24’
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If we limit the stress on the brace to Anything Less than Ultimate (58 ksi), then…
P 12’ 322” long brace 24’
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If we limit the stress on the brace to Anything Less than Ultimate (58 ksi), then…
P 12’ 425” long brace 132” The brace would not extend more than 103” (do the math: eL = 103”) 24’
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If we limit the stress on the brace to Anything Less than Ultimate (58 ksi), then…
P 12’ 425” long brace 132” The brace would not extend more than 103” (do the math: eL = 103”) And the column would be leaning by about 132” (do the math: its fun, complicated) 24’
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Now, we’re in the world of 2nd order effects (the Statics are changed because of the huge change in geometry P 12’ 425” long brace 132” The brace would not extend more than 103” (do the math: eL = 103”) And the column would be leaning by about 132” (do the math: its fun, complicated) 24’
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Gravity loads will make it collapse
12’ 425” long brace 132” The brace would not extend more than 103” (do the math: eL = 103”) And the column would be leaning by about 132” (do the math: its fun, complicated) 24’
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So….We DO NOT WANT THE MEMBER TO YIELD
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YIELD IS THE LIMIT FOR THE MEMBER
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But…The connection is different
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Around holes, a little bit of yielding is fine (holes are tiny).
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