bolted tension connections. limit state: yield or ultimate?? yield: 36 ksi (strain = 0.0013)
TRANSCRIPT
![Page 1: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/1.jpg)
Bolted Tension Connections
![Page 2: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/2.jpg)
Limit State: Yield or Ultimate??
0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.40
10
20
30
40
50
60Stress-Strain for A36 Steel in Tension
Strain (in/in)
Stre
ss (k
si)
Ultimate: 58 ksi (strain = 0.32)
Yield: 36 ksi (strain = 0.0013)
![Page 3: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/3.jpg)
Limit State: Yield or Ultimate??
0 0.1 0.2 0.3 0.40
102030405060
Strain (in/in)
Stre
ss (k
si)
12’
24’
![Page 4: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/4.jpg)
Limit State: Yield or Ultimate??
0 0.1 0.2 0.3 0.40
102030405060
Strain (in/in)
Stre
ss (k
si)
12’
24’
P
322” long brace
![Page 5: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/5.jpg)
mmmm….. Maybe we should not let it yield
0 0.1 0.2 0.3 0.40
102030405060
Strain (in/in)
Stre
ss (k
si)
12’
24’
P
322” long brace
![Page 6: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/6.jpg)
mmmm….. Maybe we should not let it yield
0 0.1 0.2 0.3 0.40
102030405060
Strain (in/in)
Stre
ss (k
si)
12’
24’
P
322” long brace
![Page 7: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/7.jpg)
If we limit the stress to less than yield, then….
0 0.1 0.2 0.3 0.40
102030405060
Strain (in/in)
Stre
ss (k
si)
12’
24’
P
322” long brace
![Page 8: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/8.jpg)
If we limit the stress to less than yield, then….
0 0.1 0.2 0.3 0.40
102030405060
Strain (in/in)
Stre
ss (k
si)
12’
24’
P
322.4” long brace
The brace would not extend more than 0.4” (do the math: eL = 0.4”)
![Page 9: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/9.jpg)
If we limit the stress to less than yield, then….
0 0.1 0.2 0.3 0.40
102030405060
Strain (in/in)
Stre
ss (k
si)
12’
24’
P
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
![Page 10: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/10.jpg)
Then again…. Yield is no where near the maximum the steel can take.
0 0.1 0.2 0.3 0.40
102030405060
Strain (in/in)
Stre
ss (k
si)
12’
24’
P
322” long brace
![Page 11: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/11.jpg)
Then again…. Yield is nowhere near the maximum stress the steel can take.
0 0.1 0.2 0.3 0.40
102030405060
Strain (in/in)
Stre
ss (k
si)
12’
24’
P
322” long brace
![Page 12: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/12.jpg)
I mean…. Even if it yields at 36 ksi, it doesn’t break, right?
0 0.1 0.2 0.3 0.40
102030405060
Strain (in/in)
Stre
ss (k
si)
12’
24’
P
322” long brace
![Page 13: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/13.jpg)
I mean…. Even if it yields at 36 ksi, it doesn’t break, right?
0 0.1 0.2 0.3 0.40
102030405060
Strain (in/in)
Stre
ss (k
si)
12’
24’
P
322” long brace
![Page 14: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/14.jpg)
It seems like yielding is no big deal
0 0.1 0.2 0.3 0.40
102030405060
Strain (in/in)
Stre
ss (k
si)
12’
24’
P
322” long brace
![Page 15: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/15.jpg)
It doesn’t break at 36 ksi (yield)Why not just say that 58 ksi (ultimate) is the limit??
0 0.1 0.2 0.3 0.40
102030405060
Strain (in/in)
Stre
ss (k
si)
12’
24’
P
322” long brace
![Page 16: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/16.jpg)
It doesn’t break at 36 ksi (yield)Why not just say that 58 ksi (ultimate) is the limit??
0 0.1 0.2 0.3 0.40
102030405060
Strain (in/in)
Stre
ss (k
si)
12’
24’
P
322” long brace
![Page 17: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/17.jpg)
If we limit the stress on the brace to Anything Less than Ultimate (58 ksi), then…
0 0.1 0.2 0.3 0.40
102030405060
Strain (in/in)
Stre
ss (k
si)
12’
24’
P
322” long brace
![Page 18: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/18.jpg)
If we limit the stress on the brace to Anything Less than Ultimate (58 ksi), then…
0 0.1 0.2 0.3 0.40
102030405060
Strain (in/in)
Stre
ss (k
si)
12’
24’
P
425” long brace
The brace would not extend more than 103” (do the math: eL = 103”)
132”
![Page 19: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/19.jpg)
If we limit the stress on the brace to Anything Less than Ultimate (58 ksi), then…
0 0.1 0.2 0.3 0.40
102030405060
Strain (in/in)
Stre
ss (k
si)
12’
24’
P
425” long brace
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)
132”
![Page 20: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/20.jpg)
Now, we’re in the world of 2nd order effects (the Statics are changed because of the huge change in
geometry
0 0.1 0.2 0.3 0.40
102030405060
Strain (in/in)
Stre
ss (k
si)
12’
24’
P
425” long brace
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)
132”
![Page 21: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/21.jpg)
Gravity loads will make it collapse
0 0.1 0.2 0.3 0.40
102030405060
Strain (in/in)
Stre
ss (k
si)
12’
24’
P
425” long brace
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)
132”
![Page 22: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/22.jpg)
So….We DO NOT WANT THE MEMBER TO YIELD
![Page 23: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/23.jpg)
YIELD IS THE LIMIT FOR THE MEMBER
![Page 24: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/24.jpg)
![Page 25: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/25.jpg)
But…The connection is different
![Page 26: Bolted Tension Connections. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)](https://reader035.vdocuments.mx/reader035/viewer/2022062409/5697bfec1a28abf838cb86a9/html5/thumbnails/26.jpg)
Around holes, a little bit of yielding is fine (holes are tiny).