When CJP welding a column with a 2" thick flange to a 2" thick base plate (to achieve base fixity of the column) what are the pitfalls with regard to making the weld? Any concerns with delamination of the thick material or tearing of the weld in such an application? This is in an area of low...
When using Factory Mutual or NFPA data sheets to determine pressures caused by combustible dusts, are those resulting pressures service or ultimate loads?
It makes sense to me that these would be ultimate loads (which can be used with the ASCE extraordinary even load combinations of 7-16...
I have a few questions for those of you who have dealt with large scale rack structures. I am particularly interested in the type which are framed with regular hot rolled sections and which are, themselves, buildings where the cladding is supported from the rack structure. Seismic Design...
I would like to increase the weld size on an existing double-angle brace connection from 3/16" to 5/16".
Is this permitted by AISC? Is there an established procedure to do this? Since this is in a tough spot to access, the less grinding the better.
Obviously proper fusion is a concern, but it...
I cannot find where weak-axis column connections for SCBFs are specifically disallowed by the manual. Am I correct to presume that this is permitted? All the connection design examples seem to be with the braces connecting to the column flange. Why?
What are the pitfalls to look for when...
I have searched Google to no avail, so now I’m turning to the even more powerful eng-tips forum members.
We have been seeing a type of shear connection where the web of a tee is fitted perpendicular to a girder web and the connecting beam is bolted through the flange of the tee using an...
My apologies for he re-post, but I posted this in the OSHA forum and could hear the ckickets whilst I was typing.
I was able to easily find OSHA's requirement for non-slip ladder rungs in 1926: "1926.1053(a)(6)(i) The rungs and steps of fixed metal ladders manufactured after March 15, 1991...
I was able to find OSHA's requirement for non-slip ladder rungs in 1926: "1926.1053(a)(6)(i) The rungs and steps of fixed metal ladders manufactured after March 15, 1991, shall be corrugated, knurled, dimpled, coated with skid-resistant material, or otherwise treated to minimize slipping..."...
ASCE dictates that we assign site class basd on the profile in the top 100' of soil. If there is a significant basement under the building, is the correct procedure to evaluate the 100' of soil below the basement level?
I have seen this done but I don't see it specifically addressed in the...
Does section 6.2 of NFPA 61 ("Enclosure Requirements") apply to silos (interior to a building) or is a silo a piece of equipment? Intuitively, it would seem that a silo is equipment, but Exception No. 2 under 6.2.1.2 specifically seems to pertain to silos (i.e. "Bins and Silos"). Chapter 7...
AISC says that "through-plate connections should be used when the HSS wall is classified as a slender element". I understand that this applies to single plate shear connections and when you have to go to a through plate. Does the slenderness limit apply to other types of HSS connections, such as...
We are soon submitting a small commercial building for permit in the city of Des Moines.
My Architect is telling me that bound calculations are required for submittal. While I know it is in the Code to submit calculations, it is unusual in the Midwest to actually do so.
Is anybody out there in...
We have come across an existing situation where some lightly loaded building columns are bearing on a rowlock header course of brick. The brick is not solid - it has two rows of decent-sized holes. Given the strrength of brick I'm sure the brick in this orientation has some capacity, but how...
http://www.statesman.com/blogs/content/shared-gen/blogs/austin/investigative/entries/2009/09/16/another_whitco_pole_topples.html
Evidently there is a massive recall for light poles manufactured by Whitco LP and sold in the last ten years. Generally these are poles over 70 feet tall. While there...
We are the EOR for a building for which blast effects will be a major consideration. While we have a moderate amount of experience in blast design we are hiring a sub-consultant to provide and refine the dynamic analysis. The framing for the entire building (blast effected and non-blast...
What are the pitfalls (if any) with design of a composite floor system using HSS shapes? Is there any shear "lag" of sorts to consider given that the studs will be welded in the middle of the relatively flexible top horizontal face? Are there any specific/special Code provisions which apply...
We have a 50' tall x 100' wide single slope PEMB with a 40 ton crane. The crane will be tied to the building but will have its own columns. The use of the crane is such that I'm calling it a service class D. Seismic is not an issue.
What sway do you all allow for such a building? Would you use...
We are looking at a job in NE Arkansas. We will be getting a copy of the current State code but I was hoping someone on here could give me a heads up on whether or not the State has its own provisions which override (and soften) the provisions of the IBC and ASCE 7-05.
I believe as recently as...
Is there an online resource for seismic hazard maps for Mexico? Everywhere I look references back to a global hazard map at http://earthquake.usgs.gov/regional/world/mexico/images/mexico_haz.gif . Are there better, more specific maps available? What is your experience designing in Mexico?
