I'm using AISC Design Guide 1 - in my situation I have a horizontal cantilever tube imparting the moment on the plate. There is no axial force P, plate dimensions N=11", B=11". Following the examples, I used e=M/P which goes to infinity, so e>e-crit so I have a large moment case.
Going...
Hi, I have a question on calculating deflection on sloped wood roof rafters. I'm working on a project where I am checking existing roof rafters on a residence. I have calculated my dead and live loads on the horizontal projection and using the horizontal span of the rafter to check strength...
NDS Table 11.5.1C shows spacing requirements between fasteners in a row. For loading perpendicular to the grain, and to allow the geometry factor C-delta to be 1.0, the table says the spacing requirement, paraphrasing here, is "spacing required by attached members." For C-delta less than 1 and...
Please pardon for the elementary question here I have on section modulus.
On a particular project I am working on, there is a timber built-up beam I am analyzing for capacity. Basically it is built-up out of three pieces of wood - a large rectangular beam, and then located on each side of the...
BA, we believe that at the time the slab was originally designed and constructed, it was done using WSD so we're trying to check the slab based on those design principles matching what was done back in those days.
Hi all. Am working on analyzing an old concrete slab/T-beam using ACE 318-63. Calculating the section modulus of the t-beam/slab, I of course get two section moduli - one based on the distance from the neutral axis to the top of the slab St, the other from the neutral axis to the bottom of the...
escrowe:
Thanks for your posts in this thread. For me at this point, I’m not concerned with a perfect design procedure and I don’t have a specific project yet to ask specific questions on. Each project is different and no specific or perfect design procedure will fit each case anyway.
I’m...
I have the following questions on info in the CalTrans T&S Manual. Please answer if you can. Thank you.
1) Pages 6-24, 8-5 state "surcharge pressures can be added directly to the soil diagram or may be drawn separately." Example 8-1, page 8-8 says "the surcharge can't be handled in the usual...
Not much offends me. But the holier-than-thou attitude that some people exhibit in these forums is uncalled for. It's a help forum, and nothing more. Yes, people should do research first, but when they already have, there is no reason they should be told their questions are too basic or...
I'm pretty sure the HP was "used." Still, in my opinion there would be no reason to take Fy anything less than 36ksi. The determination of the allowable stress for whatever situation (bending, compression, shear, tension) as identified in the specs of the AISC manual takes into account...
I thought about that too but the math is done for the conventional method.
Another question - can surcharge pressures simply be added to the net pressure diagram? I read in the CalTrans Trenching and Shoring manual that they can't - that an equivalent height of earth must be used. Agree/disagree?
I need to clarify a couple things.
The beam was an HP 10x42. AISC 9th edition lists Fy' as 29.4 ksi. The steel was A36 steel.
He actually substituted Fy' = 29.4ksi for Fy and made the allowable stress = 0.66(29.4ksi).
The beam I believe was not laterally braced in any appreciable way.
In designing temporary / short-term sheet pile wall and soldier pile wall earth retention systems, have you in your experience checked for system stability such as heave?
Also, is shear commonly checked when designing said earth retention systems?
Please share your experiences.
I recently reviewed a simple-support steel beam design performed by an outside consultant. The consultant used ASD. Allowable stress he used to check a HP 10x42 was Fy' = 29.4ksi. Why would this have been done?
I have never seen yet in practice or in books of Fy' (value of when flanges...
Question on the USS Sheet Piling Design Manual, version 1974:
Net earth pressure diagram for a cantilever system in granualar soil is shown on page 21. I understand how it is arrived at. But why when calculating the section modulus are various pressures both part of the net pressure diagram...