cancmm
Structural
- Dec 4, 2009
- 93
After a number of years working on bridge-type structures, I'm looking at a low-rise building for one of our newer projects. As such, I have a few questions regarding moment frame and shear wall design:
1) When working with a moment frame, is there a "better" method of determining lateral stiffness than modeling the frame with a unit force and correlating that to deflection? Is there standard equations to use (like with shear walls) that calculate the deflections quickly and easily?
2) I read in an outdated text that concrete moment frames must be poured monolithically. Obviously this is ideal but I can already hear the contractors complaining. Unless the rebar was insufficiently developed or the friction of the joint was too weak in shear, I don't see any reason for this. Any comments?
3) For moment frames with shallow footings, is it common to connect the footings with a strap rather than isolating each footing?
4) If a shear wall (or frame) is angled 45 degrees from the principal lateral load direction, how does it contribute to the stiffness of the system? (cos45? Neglected?)
Thanks!
1) When working with a moment frame, is there a "better" method of determining lateral stiffness than modeling the frame with a unit force and correlating that to deflection? Is there standard equations to use (like with shear walls) that calculate the deflections quickly and easily?
2) I read in an outdated text that concrete moment frames must be poured monolithically. Obviously this is ideal but I can already hear the contractors complaining. Unless the rebar was insufficiently developed or the friction of the joint was too weak in shear, I don't see any reason for this. Any comments?
3) For moment frames with shallow footings, is it common to connect the footings with a strap rather than isolating each footing?
4) If a shear wall (or frame) is angled 45 degrees from the principal lateral load direction, how does it contribute to the stiffness of the system? (cos45? Neglected?)
Thanks!
