几何尺寸与公差论坛

 找回密码
 注册
查看: 813|回复: 0

2006 ibc seismic design

[复制链接]
发表于 2009-9-7 08:28:47 | 显示全部楼层 |阅读模式
2006 ibc seismic design
i am trying to wrap my arms around this. i am just trying to get a broad over view of the design method. for example this is how i believe it works.
1)    sds sd1
2)    building period
3)    seismic base shear
4)    later force @each story
5)    ?
6)    ?
i am just trying to make sure i have the procedure correct. could someone give me a boot in the correct direction?
thanks for the help..

brief summary of seismic design steps
1.  determine location of project and find s1 and ss.
2.  determine site classification (a-f) and get fa and fv  
     factors
3.  determine sds and sd1
4.  determine seismic design category from sds
     and sd1
5.  if sdc = a, then use the 0.01w load for e in load
      combinations
6.  if sdc = b or above, then determine whether
     the 鈥渟implified method鈥?or standard method is
     applicable (simplified is usually for light framed
     construction or lower buildings with flexible
     diaphragms throughout).
7.  develop the type and layout of the bracing system
8.  determine the r, ωo, and
     cd factors for the system chosen
9.  calculate a ρ factor (reliability factor) based
     on number and features of the bracing system.
10. determine the period of the building
11. determine the base shear v either from the simplified
     or standard methods.
12. determine the vertical distribution of the base shear
     at each level (formula given for each fx)
13. analyze the building for deflections and member forces.
     using the definition of
     e = ρqe +/- 0.2sdsd
     in the code load combinations.
14. determine if pδ effects are required to be
     included in the design.
15. design members
thanks jae that helps.
i guess it would be your number 15, 16 and torsion that confuses me. i will start with 16.
#16 detailing procedures. i want to make sure i understand this correctly. after i get my design done i go into the applicable code pull out the design info for the connections. (this is not specified in the asce)
#15 the vertical design, how do you apply this to a horizontal   
detailing - for steel design, the aisc seismic specification pretty well outlines what is required.  the theory behind this is that you design all the brittle, non-ductile connections for higher loads (times the omega factor) to ensure ductile failure mechanisms.  same for concrete - more attention paid to beam/column interfaces to ensure a ductile and non-brittle failure.  to go into all the details here is impossible.  you just need to understand all the specified requirements - again - for steel look through aisc if that is your applicable spec.
#15 - not sure what you mean by "vertical design" in light of what #15 is saying.
torsion:  i think you are close in your understanding.  basically the building codes have specific instances when the application of the story shear is required to be applied at a slight horizontal distance off from the actual center of mass - separately in each direction.  this produces either a further, or closer, eccentricity between your center of mass and center of rigidity, which produces horizontal torsion in the floor/roof diaphragm.  this then induces higher and lower lateral forces in the braces on each side of the floor system.

# 15, i was asking how your vertival loads are applied in reference to you   
vertical loads are in the ibc load combination in the form of 0.2(sdsd.
vertical distribution of the horizontal base shear is per the ibc - where there is an equation for f at each level of the building.
which are you referring to?

fasboater,
there is a good article on the internet, in the april 08 edition of gostructural.com, titled "2006 ibc section 1605.2.1".
the article outlines, with some examples, what jae has been describing for you.
hope that this helps.   
follow the link below for very detailed analysis and design examples for seismic design.
您需要登录后才可以回帖 登录 | 注册

本版积分规则

QQ|Archiver|小黑屋|几何尺寸与公差论坛

GMT+8, 2024-5-19 00:22 , Processed in 0.036317 second(s), 19 queries .

Powered by Discuz! X3.4 Licensed

© 2001-2023 Discuz! Team.

快速回复 返回顶部 返回列表