AISC 341-05 section 8.5a requires column axial anchorage to be designed for the required strengths of the steel elements connected at the base. In the case of a SCBF, this would be the summation of the required column strength per section 8.3 and the vertical component of the brace connection...
Hello all!
I have a question about the attached bracing configuration for a SCBF system. For a SINGLE story structure, would this bracing configuration violate the requirements of section 13.2c of AISC 341-05? In my opinion, it does violate the requirement because the load path will result in...
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I have a project in construction with a slab on grade that is ready to receive carpet and other finish materials. The contractor tested the relative humidy and PH values of the slab, and they were higher than those recommended by the manufacturer. The manufacturer will not honor the...
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Does anyone know if there's any code requirements for the surface where the CMU will sit on a concrete slab? I.E. does the concrete surface need to be roughened to a minimum amplitude?
Thanks!
Dear All,
I am modeling a sloped metal deck in ETABS. My first question is, do you all typically use a shell element to do this or the ETABS built in Deck Section modeler? For those that use shell elements, what method do you use to come up with an equivalent thickness of the deck to assign...
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I have a steel framed tower that will be clad with precast concrete panels. The floor to floor height is 11'-8" on the tower. The maximum width of the panel is about 17' per the architectural elevations. I'm planning to use 5" panels with 3/4" reveals. The panel design is delegated...
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I have a project with 30' deep piles currently in construction. The contractor has driven test piles and is testing them for lateral load capacity in accordance with ASTM D3966. He has indicated that the piles are failing the required capacity miserably. I am having him test another...
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Just wanted to get some confirmation from others that the requirements of Appendix D are not required for non-structural element anchorage. I am hanging an LCD screen from an existing concrete over metal deck floor. If I have to follow the requirements of App D and apply the 0.75...
Does anyone have any insight on aggregate base under a building slab (used as a capillary break) being substituted with CMB? My research so far hasn't turned up anything negative. Thoughts?
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I wanted to get some opinions on HSS columns placed inside of metal stud walls of the same width. i.e. an HSS6x6 placed inside of a 6" metal stud wall. I know i've heard that it should be avoided due lack of construction tolerances, but i'm wondering if anyone has any real...
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Does anyone have any experience with Rammed Earth Construction? I'm about to start a highly sustainable commercial-type project in New Mexico and rammed earth is being considered for the envelope. I've been searching google for information, but most things I find are not technical in...
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I'm currently working on a project where our geotechnical engineer has stated that we can expect seismically induced settlements ranging between 3.29" to 3.39" and differential seismic settlements ranging between 1.64" and 2.23". The depth of the liquefiable layer is fairly deep at...
Does anyone know how to calculate the plastic moment capacity of a composite shape with varying Fy? For example, a wide flange beam (Fy=50ksi) with channels welded to the top and bottom flanges (Fy=36ksi)? I did it by summing the moment capacity of the wide flange beam and the moment capacity...
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Are there any good references out there for designing connections for beams with torsion? For example, a curved HSS member uniformly loaded along its length. Any help would be appreciated.
Thanks
Hi all,
I'm currently working on a project that will have a trellis on the exterior. This trellis will be exposed steel HSS tubes. The trellis itself will be delivered in components and assembled in the field. The architect wishes to have all connections welded rather than bolted. Now...
Hi all,
I'm currently working on a project that will have a trellis on the exterior. This trellis will be exposed steel HSS tubes. The trellis itself will be delivered in components and assembled in the field. The architect wishes to have all connections welded rather than bolted. Now...
Hi everyone,
Do any of you have experience with specifying recycled content of steel shapes? With so much emphasis on green buildings and LEED these days, I've been having to specify recycled content percentages in steel shapes in my specifications. Anyone done this before and have a general...
Hi everyone,
I've been given a steel shop drawing for guardrails to check. I noticed the steel fab is using 1-1/2" diameter ASTM A513 grade tubes. I looked in my steel manual and could not find this grade of steel. A quick google search for the yield strength gives a range of 30-80 ksi...
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I'm designing lateral bracing for a mechanical unit and I have a question regarding the use of steel cables. Does anyone know of a standard to follow for determining the strengths of cables? I can't seem to find any information on the steel grades, yield strengths, etc. I'm also...
