Seismic Design Category is C. It is permitted under the Ordinary Moment Frame, but i totally understand. Fortunately its not very heavy, only grating for dead load other than self weight and its all open so just wind pressure on the face of the members so there isnt a ton of lateral loading and...
Update: Ry is not the R value from the table it is the ratio of the expected yield stress to the specified minimum yield stress. Also, if anyone could provide a design example thatd be helpful. I have the value now but it is in k-ft and im wondering how to put that into a tension/compression...
I am designing an exterior stair, so its subject to wind loads as well as seismic. For the seismic design, i am looking at Chapter 15 of ASCE 7-16 for nonbuilding structures similar to buildings. This stair isnt part of the lateral system and isnt detailed to attach to the building, so it has to...
Yes the weld is shown in the wrong place in the first attachment. It should be shown at the Column as i show in the second attachment, but still the same weld shape shown in the first attachment. And i know that Ip=Ix+Iy, but how do i get the Ix and Iy when you treat the welds as lines?
Ahh i see the confusion, here is a plan detail. There is an angle and its bolted to the channel but welded to the HSS column. Im looking at the weld to the column as the bolts are good.
https://res.cloudinary.com/engineering-com/image/upload/v1632406137/tips/Plan_View_Weld_cwgwfo.pdf
Can someone give me some guidance on how to determine the Ip for this weld group so i can determine if it is adequate for the bending force being applied to it due to eccentricity? I have found the Center of Gravity of the weld group but am having a hard time recalling how to get the Ip. In the...
@dik, I am ignoring the (1A1) connection because i cant get the allowable load. So my client added in the L4x4's with the Titen HD's @ 12" oc to take the load. Basically im wondering if i can distribute some of the load that the 1st bolt (closest to (1A1)) is seeing to the rest of the bolts in...
So as seen in the picture below, i have a stringer that was supposed to be connected to the wall using the 6 bolts in the bent plate (1A1) but the wrong bolts were installed that needed a spacing of 20"+ which obviously is not there. I cant get any values for the bolts that were used as the...
Why do you guys think that? The X bracing ties the landings together and helps stiffen the stair in the X direction. This is shown in the model. Obviously not saying that just because the model says its right that it is right, just curious why you dont like it.
So i ended up not modeling the concrete deck using plates because when i released the moments at the corners i ended up getting the same divergence issue as before. While the concrete deck will brace the landings somewhat, i dont think i could jsutify them being moment connected to the...
Yeah so the only way i can get the model to work is to increase the size of the stringers to C15's to increase stiffness. The issue then is a headroom issue with the now bigger stringer. Unfortunately the stair is kind of out in the open so connecting the landings to get some resistance in the X...
I agree with both of you, there is an instability issue because of the hanger system with this stair. My main concern is why when i add in the concrete plates in the model, it stiffens it up enough where i dont have an instability issue and all the original shapes work. So im trying to determine...
Anyone have experience modeling stairs in Risa3D? Was having convergence issues with this stair because of the unique hanger situation (Typ C12x20.7 stringers, C7x9.8 Flight headers, 1" dia. hanger rods)at the 4th landing, back left corner. Because of the supports it was twisting and pushing the...
dauwerda: its going to be a field weld, not sure exactly which process. I already brought up to my client, who then relayed it to the EOR, that it is just a recommendation but they said that they want calculations to prove that it is fine without that shelf distance.
DrZoidberWoop: Thanks for...
I am getting feedback from the EOR saying that a MC12x14.3 flange does not have enough space to fit a 1.66" OD Pipe with a 3/16 fillet weld all around. This is unusual because this is an industry standard and the fillet weld is capable of withstanding the applied loads. The EOR is asking for...
I have a moment connection of a W beam to an HSS column. CJP weld of the flanges to the face of the column and a shear tab welded to the column and welded to the web of the beam. Capacity is not the issue but rather HSS Limitations as i have a W16x31 in one case and a W18x35 framing into a...
How am i supposed to go about determining if the weld can take these loads applied? There is the vertical shear and the horizontal axial load applied. See the attached pdf. Thanks for you help!
Yeah youre right, i ran the numbers and a stiffener is overkill. The plate itself is adequate even for the cantilever with the handrail attached. That being said, my boss just wants that extra security at the handrail locations.
