Steel Joist Uplift Calcs
Steel Joist Uplift Calcs
(OP)
I am a project manager for a commercial gc in tampa. The SE on my project says he needs the uplift calcs on the open web steel joists before he will approve the shop drawings. Our fabricator (Nucor) is stating that the calcs cannot be determined until the joists are fabricated. This is a cath 22. Who is right? Any insight would be appreciated.






RE: Steel Joist Uplift Calcs
If the forces are provided, I don't understand Nucor's response. They are responsible for fabricating the joists. They should know what their properties are and can use these properties in designing them.
RE: Steel Joist Uplift Calcs
Under Florida law this is a delegated function, specifically covered by the rules of the Board of Professional Engineers. They (Nucor) are obligated to provide the SEoR with adequate information (at his determination) to review and approve the shop drawings.
RE: Steel Joist Uplift Calcs
I live in Florida and have been practicing structural engineering her since the mid 80s. The SEOR of record is responsible for the entire structural integrity of any structure he designs. He may delegate the design of parts and portions of the structure according to Florida Administrative code. I like to point you to part 61G15-31.006 “Design of Structural Systems Utilizing Open Web Steel Joists and Joist Girders of the rules. These rules can be found at this link: h
Rule 61G15-31.006 specifically states "The Engineer of Record may require the submission of the steel joist and joist girder design calculations as an indication of compliance. When required to submit the steel joist and joist girder calculations, the steel joist and joist girder manufacturer shall submit a cover letter along with the steel joist and joist girder design calculations. The cover letter shall bear the seal and signature of a Florida registered professional engineer responsible for design of the steel joist and joist girders.”
What I usually do is require the shop drawings and the calculations to be submitted at same time. Then I can review the calculations and the shop drawings at same time. I normally specify the joist size and any special loading on the joists on my design plans. I indicate the minimum bridging and I require that the joist receive uplift bridging on the bottom chords per SJI specifications.
I am very familiar with Vulcarft (NUCOR) and they are intimately familiar with these requirements. I must say I never had a problem with them furnishing the calculations nor the shop drawings before fabrication I may add. If hey fabricate before approval they are taking a huge risk. I see shop drawing approval process not only as compliance but dimensional check by the contractor and also an engineer’s last resort to catch any “errors” before fabrication.
I indicate on my plans either the net uplift pressure or I indicate the gross uplift pressure on zones 1, 2 and 3 of the roof (this is FBC and ASCE 7 terminology). If I provide gross uplift pressure I do provide the dead load and let the joist engineer determine the net uplift.
I think you are misquoting the joist manufacture. They are not supposed to fabricate the joists until the shop drawings and calculations have been reviewed. They also cannot fabricate the joists till they run the calculations first. Therefore, I see no catch 22 situation. You may want to talk with the engineer and the joist suppliers in a conference call to clear any confusion. YOU MUST SUPPLY THE CALCULATIONS TO THE EOR.
Good luck.
RE: Steel Joist Uplift Calcs
Happy Turkey Day to all
RE: Steel Joist Uplift Calcs
RE: Steel Joist Uplift Calcs
I truly appreciate your expertise in this subject.
RE: Steel Joist Uplift Calcs
Two related issues that DO sometimes crop up- can't get material test records until material is delivered (to the fabricator)- or can't get welder certifications until welders are assigned. But calcs should be no problem.
RE: Steel Joist Uplift Calcs
I am heading to the mountains of West Virginia. I can smell the wood and coal buring fire places. Country Roads, take me home... to the place I belong...
I think everyone knows the rest.
Bye to all for now.
RE: Steel Joist Uplift Calcs
Also, we always show a gross uplift diagram on our drawings showing the various specialty trades (joists, deck, roofing, etc) exactly what gross uplift loads they should use for their calculations. However, if we did not have this, they would still be able to calculate it for themselves as in FLorida you are required by teh FBC to clearly state the wind design parameters on the structural drawings. This way, any specialty engineer, from anywhere, can correctly calculate the wind pressures for the particular building/site conditions.
I think Lutfi is right on. There is definitely some break down in the communication process here that a conference call would clear up right away, I am sure.