Recent content by PROYECTOR

Hi dik, AISC Design Guide 24 has a quite conservative design procedure for this condition, where the bending moment due to the lap eccentricity is evenly distributed between the connection plate and the gusset plate. I think it's a reasonable assumption as long as both plates have similar...

RAM Connection uses a rigid base plate model for determining the internal force distribution. So for this base plate, you won't get a realistic or accurate enough anchor rod force distribution using RAM Connection unless you provide a fairly rigid base plate. I don't think a 1-1/8" thick base...

Lomarandil, thanks for the clarification!

Yes, I think it does. However, I think you will find that a quite thick base plate is needed for the connection to work properly.

Please ignore the shear lug in the detail I just suggested.

It may work, but the outer anchor rods won't be very effective unless you provide a very stiff base plate. If that was my design, and there is no way to make it work with two anchor rods, I would use a base chair type connection (see attachment bellow).

Hi Lomarandil, where do those values come from? Some standards, like API 650, recommend using S1=1.25*PGA and Ss=2.5*PGA. In this case, PGA, as well as S1 and S2, correspond to a 2% probability of exceedance within 50 year period (maximum considered earthquake).

I just suggest that the top of the columns need to be properly braced. The elements used for that purpose (being a cold formed or a hot rolled section) need to be properly designed and connected to the roof diaphragm. Sorry, I didn't look at the floor system you are proposing, my...

I am with MIStructE, that is the best and easiest solution. 12m beams @ 3m or 2m (depending on the steel deck) seem very feasible to me. If height limit is a problem, you can use joists or castellated beams to accommodate the duct work and increase the available space. Also, I would remove the...

This is by far one of the best structural steel design books ever published, thanks for sharing!

Sorry, there is a little errata in the above calculations. The modification is indicated in red...

There is no reference, just statics assuming a plastic stress distribution in the flange plate due to minor axis bending. However, there is a quite similar approach for bolted column splices in Tamboli's book "Hand Book of Structural Steel Connection Design and Details". The equivalent flange...

If major and minor bending moments are concurrent, you can calculate an statically equivalent flange force to design the flange plate and weld. It can be calculated as: Puf = Pu/2 + (Mux/(d + tp)) + 4Muy/bp Where: Pu = Beam axial load (if any) Mux = Major bending moment Muy = Minor bending...

I recommend that you consult the book "Ductile Design of Steel Structures, Second Edition". That book has a chapter on plastic analysis and yield line theory.

I would use OMF at the front and back to avoid unnecessary torsional response. I think it could work depending on the required strength. However, if you need pinned base plates, I would not use HSS columns. In my opinion, a nominally pinned base condition is difficult to achieve in practice...