@hokie66 -- based on the short span Mll of 9 k-ft, I think the Mdl is actually 23 k-ft. It certainly appears that there is a decimal point between the 2 and the 3, but I think it is likely due to the quality of the scan.
Adam Vakiener, P.E.
Unless you want to answer some questions from the owner about this situation, I would suggest up-sizing the W8x10 to a W12x14. I had a similar situation a few years ago and the owner asked me why a small beam was used to support a larger beam. Since that time I have always tried to use at...
I am trying to determine the capacity of an existing concrete floor slab constructed using toupet tile. The existing drawings call for the joist to be spaced 13" apart. Obviously, the width of the joist will then be determined by the width of the toupet tile forms. Does anyone know how wide...
It sounds like you are describing Tectum deck. The company that produces Tectum is still in business - you should be able to get load tables from them.
Adam Vakiener, P.E.
WillisV,
Can you point me to the section of the SJI code that requires the parallel to joist load to be shown on the drawings? I was unable to find it in my copy of the 2005 SJI code. Thank you.
Adam Vakiener, P.E.
It looks like a bad detail to me. I typically weld the plate to the bottom of the lintel beam and extend the plate over the full bearing length on the masonry. This eliminates the need for a separate bearing plate. I also call for the cells below the bearing to filled with grout continuously...
I think the table in question is primarily deflection based. AISC has probably updated to using the plastic section modulus for plate bending to keep consistent with the provisions for structural shapes.
Adam Vakiener, P.E.
You could always stagger the joists to aloow the seats to extend over the beam web. This should eliminate the localized flange bending problem.
Adam Vakiener, P.E.
A typical P-M curve extends below the zero axis on the P-side. This covers the condition of tension combined with bending. There is minimal capacity for this condition as a concrete beam is tension controlled to begin with.
Adam Vakiener, P.E.
Andrew,
May I suggest that you contact D. Matthew Stuart, P.E., S.E., F.ASCE, SECB
He has written a series of articles on antiquated structural systems for STRUCTURE magazine. I know that he has an extensive catalog of proprietary joist information.
Adam Vakiener, P.E.
Maury,
Yes, 20.5 psf is correct. It is calculated simply as qh*G*Cn.
dcarr,
What table for components and cladding would you use for this type of rooftop equipment? It is neither a wall nor a roof and doesn't seem to fit the descriptions listed in Figure 6-21 for rooftop equipment.
I think...
Kz and qh are correct assuming terrain type B.
The Cn values are all correct except for Case B with gamma = 0. In this case they should be equal to -2.5 and -0.5.
Adam Vakiener, P.E.
Since an isolated slab on grade is not supported by the building structure I would not include it in the seismic weight of the structure. Anything supported on such a slab would likewise not be included in the seismic weight of the structure.
Adam Vakiener, P.E.
