1. Bolted Tension Connections

2. Limit State: Yield or Ultimate?? Yield: 36 ksi (strain = 0.0013)

3. Limit State: Yield or Ultimate?? 12’ 24’

4. Limit State: Yield or Ultimate?? 12’ 24’ P 322” long brace

5. mmmm….. Maybe we should not let it yield 12’ 24’ P 322” long brace

6. mmmm….. Maybe we should not let it yield 12’ 24’ P 322” long brace

7. If we limit the stress to less than yield, then…. 12’ 24’ P 322” long brace

8. If we limit the stress to less than yield, then…. 12’ 24’ P 322.4” long brace The brace would not extend more than 0.4” (do the math:  L = 0.4”)

9. If we limit the stress to less than yield, then…. 12’ 24’ P 322.4” long brace The brace would not extend more than 0.4” (do the math:  L = 0.4”) And the column would be leaning by no more Than 0.45” (do the math: Pythagoran

10. Then again…. Yield is no where near the maximum the steel can take. 12’ 24’ P 322” long brace

11. Then again…. Yield is nowhere near the maximum stress the steel can take. 12’ 24’ P 322” long brace

12. I mean…. Even if it yields at 36 ksi, it doesn’t break, right? 12’ 24’ P 322” long brace

13. I mean…. Even if it yields at 36 ksi, it doesn’t break, right? 12’ 24’ P 322” long brace

14. It seems like yielding is no big deal 12’ 24’ P 322” long brace

15. It doesn’t break at 36 ksi (yield) Why not just say that 58 ksi (ultimate) is the limit?? 12’ 24’ P 322” long brace

16. It doesn’t break at 36 ksi (yield) Why not just say that 58 ksi (ultimate) is the limit?? 12’ 24’ P 322” long brace

17. If we limit the stress on the brace to Anything Less than Ultimate (58 ksi), then… 12’ 24’ P 322” long brace

18. If we limit the stress on the brace to Anything Less than Ultimate (58 ksi), then… 12’ 24’ P 425” long brace The brace would not extend more than 103” (do the math:  L = 103”) 132”

19. If we limit the stress on the brace to Anything Less than Ultimate (58 ksi), then… 12’ 24’ P 425” long brace The brace would not extend more than 103” (do the math:  L = 103”) And the column would be leaning by about 132” (do the math: its fun, complicated) 132”

20. Now, we’re in the world of 2 nd order effects (the Statics are changed because of the huge change in geometry 12’ 24’ P 425” long brace The brace would not extend more than 103” (do the math:  L = 103”) And the column would be leaning by about 132” (do the math: its fun, complicated) 132”

21. Gravity loads will make it collapse 12’ 24’ P 425” long brace The brace would not extend more than 103” (do the math:  L = 103”) And the column would be leaning by about 132” (do the math: its fun, complicated) 132”

22. So….We DO NOT WANT THE MEMBER TO YIELD

23. YIELD IS THE LIMIT FOR THE MEMBER

25. But…The connection is different

26. Around holes, a little bit of yielding is fine (holes are tiny).