×
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

please rate tj-pro ratings

please rate tj-pro ratings

please rate tj-pro ratings

(OP)
Can someone comment on how well this rating system is working out in real life?
I am just starting to mess around with it on a 22.5' span. It looks like l/720 LL defl typically gets a tj-pro 45 rating.
Code minimum I-joist floors don't feel that great to me (l/360), but am I "over engineering" with
this tj-pro rating system, especially for a rating above 45?
for example, tj-pro 50 is l/1000, tj-pro 55 l/999+ approaching zero

Also, it seems like once you start telling a client how subjective floor vibrations
are, it is difficult to sound like you really know how to design a floor correctly. I can still
pull it off, but it doesn't build the client's confidence in you immediately.

RE: please rate tj-pro ratings

I have never had a floor problem and we always design for TJI rating = 50. I can't comment on if it is over-engineering, but I agree the LL ratios typically is ~1000 as you mention and therefore have pretty robust ratios. Normally, it's not too big of a deal to meet. We usually have TJI 230 x 11 7/8 spanning ~16' or so. 18' or so and we transition to 14" joists. 22.5' and we would be using at least 16" joists. At that span, we'd try to break up the span with steel beams depending on the floor layout. Floors have always felt nice and stiff.

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