I have a condition where the bottom floor of a 2 story building will be open. The end columns I have designed as moment frames. The columns are round HSS14x.625 columns. For protection, the arch would like to wrap the columns in concrete. I was thinking of having studs welded to the column so...
Thanks for all the responses. I checked with my insurance company and the NC board. NC board said I need to clearly indicate on the drawings that it is a standard design and what the criteria is for the design and provide a note that states it must be adapted for the specific site and building...
I have a client that wants me to design a steel column and bracket for a wind load of 150 mph. He wants to install this bracket all over the Country. Two questions 1. I am only licensed in a few States so he would only be able to use the design in the States I can seal for him. He says there is...
Asce 7-05 and IBC both call out for a live load of 100 psf at lobbies and first floor corridors. Is the lobby being referred to here for all floors? I generally design all upper floors of office buildings for a live load of 80 psf. You could have a large lobby area around an elevator shaft...
For fun, I've been trying to learn the Column Analogy Method. Well its not been as fun as i had imagined and i have a few questions i can't figure out. the first has to do with calculating the moment of inertia. I am following an example and have circled (2) places on each of the pages of the...
Joists are 5" wide at the bottom and taper out to 12" wide at the top. There is no taper at the ends of the span. Loads are factored.
I haven't gotten to the shear reinforcement yet, but I was planning on using carbon fiber there also. Is there a better way? A cheaper way?
Attached is a detail. Yes, sorry about that, I should be saying continuous not fixed. There aren't any stirrups. I will need to add reinforcement to the web to increase the shear strength. Based on the top bars going plastic, can I then be conservative and design the beam as a simple span and...
Yes, the joists are continuous with negative reinforcing at the girder. Under original loads, the joists do not work if you consider the ends pinned with a moment of wl^2/8 at midspan but it does work if you consider a fixed connection with a moment of wl^2/12 at the ends. This is why I assumed...
I need to increase the moment capacity of a few reinforced concrete joists by adding carbon fiber reinforcement to the bottom side only. The joists, originally built in 1958 appear to be designed with fixed ends. When I analyze them with the new loads and fixed ends, the moment is too high in...
An architect is wanting me to design a drive thru that has only 2 posts, similar to the structures they install over gas pumps. Has anyone ever designed one of these? Are the columns designed as a cantilevered column to resist lateral loads? It seem this is a very unstable structure. I've...
For an 8" slab on grade reinforced with #3 at 12" o.c. each way, is it better for the reinforcement to continue through control joints or be broken 2" each side of joint. Is a smooth, greased dowel required to allow horizontal movement but no vertical movement.
If no control joints are...
I have ordered the 75 year manual for steel joists but not gotten it yet and need to have the calculations completed tomorrow for an existing joist with a new load. Could someone please look up the allowable load and weight for a 22H7 joist. My span is 35'-1".
thanks in advance.
I have a pre-engineered building foundation I am designing. There will be a turndown around the perimeter. This building has an 8" cmu full height wall in some places. In the past i have specified an individual spread footing below the turndown to support the CMU. The contractor has requested...
I am working on a project that has steel I-beams that are encased with concrete carrying a concrete floor. From the underside of the floor there are 1'-0"x1'-0" terracotta tiles within the concrete slab. It looks like these were placed in the concrete form and the slab poured around them. In...
