×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • 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!
  • Students Click Here

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

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

T.O. Wall at Gable End Supported with Horizontal Truss

T.O. Wall at Gable End Supported with Horizontal Truss

T.O. Wall at Gable End Supported with Horizontal Truss

(OP)
Is the top of a masonry wall at a gable end typically supported with a horizontal truss?  I have a 40' long wall with a starting height of 16' and a peak height of about 33'.  I am going to use a gable end truss over the wall and am considering using a horizontal truss, spanning between the perpendicular walls, to brace the top of the masonry.  Thanks in advance.

RE: T.O. Wall at Gable End Supported with Horizontal Truss

Sounds like a good approach to me.

RE: T.O. Wall at Gable End Supported with Horizontal Truss

I'm sorry to get into this so late BUT, could you post a sketch?  I'm thinking that the truss you are talking about would have to be designed for both wind pressure and suction, so the truss has stress reversal - yes? And, how do you support the truss that supports the masonry wall, is it hung from the bottom chord of the roof trusses?

 

RE: T.O. Wall at Gable End Supported with Horizontal Truss

A sketch or couple of sections would be good as I am having a problem relating the 16 foot height to the 33 foot height, still supporting the top of the wall.  

Are the tops of the walls at the same height?  If so, no worries.

If not, I see a possible problem with a knuckle joint at the top of the CMU.

Mike McCann
MMC Engineering
Motto:  KISS
Motivation:  Don't ask

RE: T.O. Wall at Gable End Supported with Horizontal Truss

I think he has a 16' high masonry wall, then above that is a timber framed gable.  He is bracing at the ceiling level with a horizontal truss spanning the 40' dimension.

RE: T.O. Wall at Gable End Supported with Horizontal Truss

Ahh.. got it.  Thanks Hokie.

Mike McCann
MMC Engineering
Motto:  KISS
Motivation:  Don't ask

RE: T.O. Wall at Gable End Supported with Horizontal Truss

(OP)
Correct Hokie....except the gable end truss is cold formed steel.  The detail may clear things up.  The truss spacing is 4'0" o.c.    My intention is for the 1st interior truss to support the chord of the horizontal truss.  I have provided embedded plates at the top of the masonry wall (perpendicular to span) for truss attachment.  Originally, I wanted to drop the horizontal truss about 4" so it would anchor (at each end) to the face of masonry instead of the top but jogs in the wall prevented it.  Let me know if I can clear anything up.  I appreciate your input.

RE: T.O. Wall at Gable End Supported with Horizontal Truss

Lazzaroni:

Thanks for posting the sketch.  I see what you are doing, the horizontal truss braces the top of the masonry wall and the wall has a bond beam as the top course.  So, the horizontal truss must support its' own weight in the vertical direction and the wind load in the horizontal direction.  So, the horizontal truss has to take both wind pressure and wind suction - it has stress reversal based on wind direction.

1.  How do you handle that?  Is it a parallel chord truss that is anchored at the four corners to the masonry side walls?

2.  Do you have to be concerned with dumping load into the roof truss that holds the inside edge of the horizontal truss?  I think that would put the roof truss into torsion or at least bending in two directions.

3.  Do you have to worry about deflection of the horizontal truss from the applied wind load?
 

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

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!


Resources