Advantages of Hot Rolled Steel over Built up sections

[Gregorydas]

Hi all,

Our company received a design for a workshop. The designer considered all the sections as built up sections..! Even the truss works & purlin.!!. We have informed the client about the extra cost to build up the built up section and then fabricate it. And they requested us to advise the designer to replace it with hot rolled sections etc. But the designer still not agreeing to use these sections but he dont have a reason to prove it. There will be a meeting after a couple of days. Please give your experienced insights to help me make some good points about the advantages of using hot rolled sections. Not only economically but also with design terms.

Thank You.

(I am not basically a design engineer. I am not aware of the terms stress, load etc etc. but I can use it with your help)

Thanks

 

[KootK]

The only parameter of significance, and it's a big one, is cost. For the overwhelming majority of members, built up sections are fine structurally. Turn of the century steel work was almost exclusively built up members. This will be reaching a bit but some other potential problems might include:

1) Galvanizing difficulties
2) More potential fatigue issues
3) Cost of weld/bolt inspection
4) Difficulties evaluating capacity for future renos

Did the designer provide a reason for his unconventional design? Is this shop being built in the mountains of Tibet where piece weight is uber-important? Is he/she a nostalgic centenarian? There's gotta be some rationale for the built up shapes. Normally, that would be more work for the designer too. Maybe it's regurgitated from a design where one of the requirements was to use mill yard scrap?


The greatest trick that bond stress ever pulled was convincing the world it didn't exist.

 

[hokie66]

Are these "built up sections" in a "preengineered" building? If so, there may be some economy to be had in the initial construction, mainly due to automation. But in that case, you are forever and a day stuck with a bare bones structure. If the building is being designed and constructed in the traditional manner, rolled sections are generally more economical because the fabrications costs are lower.