Smart questions
Smart answers
Smart people
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Member Login




Remember Me
Forgot Password?
Join Us!

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips now!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

Join Eng-Tips
*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Donate Today!

Do you enjoy these
technical forums?
Donate Today! Click Here

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.
Jobs from Indeed

Link To This Forum!

Partner Button
Add Stickiness To Your Site By Linking To This Professionally Managed Technical Forum.
Just copy and paste the
code below into your site.

ADAMK2310 (Structural)
17 Sep 08 16:50
Given:
2-story building.
Wind controlled design.
Shearwall located under drag truss.

Is it necessary to design the drag truss to transfer the roof wind loads (wind loading on roof only) OR does it need to transfer the diaphragm loads (wind loading on roof + half of 2nd floor wall height)?

I know that the shearwall load at the top of the 2nd floor is the diaphragm load, but is it necessary to design my drag truss for this total load?

 
JAE (Structural)
17 Sep 08 17:25
Is the truss under the roof or under the floor?
JKStruct (Structural)
17 Sep 08 17:29
Do you have any diphragm at the truss bearing elevation?  Or is the wind load carried up the diaphragm attached to the top chord of the truss?  If it's the latter, then yes, design for the roof wind load and half the wall height.  Think of the section of wall exposed to wind between two shear walls.  Wind blows on the wall, half travels to the 2nd floor diaphragm, and half to the top of wall/truss bearing.  Since the diaphragm is on the top chord of the trusses, your collector truss has to transfer this down to the shear wall.   
msquared48 (Structural)
17 Sep 08 20:13
As I understand the question, the drag truss would only have to drag in the forces from the roof diaphragm to the shear wall underneath, let's call it shear wall "A", shear wall "A" being between the second floor and roof diaphragms.  

If there is a shear wall "B" below shear wall "A", then that shear wall would see roof plus second floor lateral forces, but not shear wall "A".  

Mike McCann
MMC Engineering

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close