R**********n
发帖数: 1109 | 1 Dear friends:
I met a problem in the desin of frame members in a building frame system.
The lateral load is taken by the shear wall. I consider the earthquake loads
and wind loads in the design of column and beams. However, my supervisor
said that I only need to consider the gravity loads in the design of those
members because we do not rely on them to resist lateral loads. But I do not
agree. Becausse physically, the earthquake and wind load still have effect
on beams and columns even though we |
M*********r
发帖数: 228 | 2 I suggest you ask your supervisor that what components, other than beams and
columns, can resist lateral loads.
I guess the reason you supervisor said so in your case is the earthquake
loads
and wind loads are not siginificant enough to be considered in actual
design. Only satisfying some construction criterion would be enough.
loads
not
effect
【在 R**********n 的大作中提到】
: Dear friends:
: I met a problem in the desin of frame members in a building frame system.
: The lateral load is taken by the shear wall. I consider the earthquake loads
: and wind loads in the design of column and beams. However, my supervisor
: said that I only need to consider the gravity loads in the design of those
: members because we do not rely on them to resist lateral loads. But I do not
: agree. Becausse physically, the earthquake and wind load still have effect
: on beams and columns even though we
|
R**********n
发帖数: 1109 | 3 Thanks for Mingforever.
The lateral load resisting system is concrete shear wall. If follow my
supervisor's direction, I am concerned that the some columns/beams might
collapse in an earthquake even though the whole building will not collapse (
since the shear wall is strong enough.)
Dick
and
【在 M*********r 的大作中提到】
: I suggest you ask your supervisor that what components, other than beams and
: columns, can resist lateral loads.
: I guess the reason you supervisor said so in your case is the earthquake
: loads
: and wind loads are not siginificant enough to be considered in actual
: design. Only satisfying some construction criterion would be enough.
:
: loads
: not
: effect
|
w***e
发帖数: 40 | 4 Your supervisor is completely right. |
R**********n
发帖数: 1109 | 5 Could you give me more hints about why?
I still think the column designed according to gravity load might be damaged
in an earthquake.
Thank you : )
【在 w***e 的大作中提到】
: Your supervisor is completely right.
|
w***e
发帖数: 40 | 6 One of the lateral force resisting systems is called "building frame system"
.
A building frame system has separate systems to provide support for lateral
forces and gravity loads. A frame provides support for all the grivity loads
with independent shear walls or braced frames resisting all lateral forces
. |
t******o
发帖数: 467 | 7 For rigid diaphram building, lateral loads distribution will be based on
stiffness. Typically your concrete shear walls will have relatively much
higher stiffness then other beams/columns. Therefore, concrete shear walls
will take 100% lateral loads for design purpose.
Your supervior is correct.
loads
not
effect
【在 R**********n 的大作中提到】
: Dear friends:
: I met a problem in the desin of frame members in a building frame system.
: The lateral load is taken by the shear wall. I consider the earthquake loads
: and wind loads in the design of column and beams. However, my supervisor
: said that I only need to consider the gravity loads in the design of those
: members because we do not rely on them to resist lateral loads. But I do not
: agree. Becausse physically, the earthquake and wind load still have effect
: on beams and columns even though we
|
R**********n
发帖数: 1109 | 8 谢谢 Mingforever， whype，tedamiao 。 我想我理解你们的意思，就是在考虑抗侧力
体系时，不计入柱和梁的贡献，这个我能理解。但是实际的地震过程中，梁和柱肯定也
受到因地震引起的应力的增加。 Think the problem physically, 地震力士普遍作用
与结构上的，结构的惯性力可定也可以通过板传给柱和梁， 虽然比例很小。
我的柱和梁的设计是从ETABS Model 中得到的轴力和弯矩（产生这些力的荷载组合多数
包括了地震力）。所以很多截面的配金很多。 |
n**********b
发帖数: 114 | 9 When you design shear wall buildings, the column and beams (except link
beams between shear walls) should be considered only under gravity load. So
if you design columns and beams under the lateral load, you will get a wrong
reinforcement plan. Or if you shear walls is very small relative to the
columns, you may consider the building as a combined frame and shear wall
building, which is called bearing walls building in ACI318-08 (I may be not
correct about this since my ACI is in the office.)
【在 R**********n 的大作中提到】
: 谢谢 Mingforever， whype，tedamiao 。 我想我理解你们的意思，就是在考虑抗侧力
: 体系时，不计入柱和梁的贡献，这个我能理解。但是实际的地震过程中，梁和柱肯定也
: 受到因地震引起的应力的增加。 Think the problem physically, 地震力士普遍作用
: 与结构上的，结构的惯性力可定也可以通过板传给柱和梁， 虽然比例很小。
: 我的柱和梁的设计是从ETABS Model 中得到的轴力和弯矩（产生这些力的荷载组合多数
: 包括了地震力）。所以很多截面的配金很多。
|
R**********n
发帖数: 1109 | 10 Thank you, needagoodjob. I think the building system you are talking about
is called dual system in UBC 97 : )
It seems that I have to design the beams and columns under wind load case,
however, I still think it is more reasonable to design the frames also uder
seismic load, even though we do not depend on them to resist earthquake load.
So
wrong
not
【在 n**********b 的大作中提到】
: When you design shear wall buildings, the column and beams (except link
: beams between shear walls) should be considered only under gravity load. So
: if you design columns and beams under the lateral load, you will get a wrong
: reinforcement plan. Or if you shear walls is very small relative to the
: columns, you may consider the building as a combined frame and shear wall
: building, which is called bearing walls building in ACI318-08 (I may be not
: correct about this since my ACI is in the office.)
|
s*****y
发帖数: 146 | 11 if the total weight of new members is not great than 5% of the existing
structure, the effect due to gravity or lateral loads of new addings to
exsting shall be ignored. |
R**********n
发帖数: 1109 | 12 Thank you, snowboy : )
【在 s*****y 的大作中提到】
: if the total weight of new members is not great than 5% of the existing
: structure, the effect due to gravity or lateral loads of new addings to
: exsting shall be ignored.
|
