Hi,
I posted this thread a week ago and thank you for the responses.
I have a question regarding lateral torsional buckling. I have a plate that is stiffened with T-sections along its length, such that the web of the tee is welded to the plate. The plate is approximately 270 inches long...
I have a question regarding lateral torsional buckling. I have a plate that is stiffened with T-sections along its length, such that the web of the tee is welded to the plate. The plate is approximately 270 inches long and wide, with approximately 12 tees spaced 18 inches apart (approximate)...
I was adjusting my model a variety of ways and noticed that if I apply gravity as with time effects turned off, it doesn't matter if i reapply it with time effects turned on if my transient loading is a displacement time history. Results were the same whether i applied gravity or didn't apply...
I was wondering if anyone had issues or success using FSUM to extract results for a transient analysis. I applied a displacement time history to the base of my 2D model, and have been trying to get the shear and moment at different locations along the length using the FSUM command. I was able...
Thank you for your reply. Maybe i wasn't clear.
I understand that forcing the entire structure to accelerate due to the time history is not realistic. That is why I was trying to apply the displacement time history to the base. However, results do not look good as they shears and moments do...
I have a 3D model that is fixed at its base. I have both a acceleration time history and displacement time history to read into my model. I've tried 3 scenarios. First, i ran the acceleration time history on my model using using the mode superposition method. I applied the acceleration to...
Thanks for the info. It seems that the formula listed on the njb-united.com link is limited by 8.9*t/h and is a function of both thickness of slab and location of loading. While the formula i found in a structural engineering handbook (width of load + 2*0.6*a) where a is location of loading on...
I was wondering if anyone had any advice where to look for how to analyze concentrated loads on concrete decks. I've seen in AASHTO information on wheel loads. Specifically it mentions two cases, one case for a tire load with reinforcement parallel to the traffic path and one case for...
I am supporting several beams along a concrete wall, with the heaviest load being 23 kips. It was recommended to attach an angle along the wall with one row of bolts. I felt that it would be better to have a support for each beam with 2 rows of bolts to reduce the pullout force, however, I am...
The beam has not visibly deflected horizontally. Its just that if I assume the beam is braced adequately, my bending stress is approximately 80% of my allowable, while if I'm not braced adequately, my bending stress is approximately 150% of my allowable. I would say that either my concrete...
Thanks for the inputs.
This beam is an existing beam and did not have any shear studs installed. There was no metal deck form, and the concrete around the top flange has spalled along its length in various magnitudes. The fixed strut connection is a good point, that makes sense that it would...
I have 2 questions regarding the lateral bracing of beams.
First, when can a concrete deck sitting on a beam be considered to adequately brace the beam laterally? I know you can put shear studs in the beam, which would obviously brace the top flange from lateral movement. If there are no...
I am looking for opinions on the evaluation of corroded steel W-sections.
When you have a new section, it is easy enough to calculate your sectional modulus, and your maximum bending and shear stresses. Regarding your allowables, you can easily determine if you are compact, non-compact, or...
I am wondering if this connection is considered fixed or SS. Originally, it was a bolted connection, a beam with angles bolted to its web and the web of the beam it was bolted to. Due to existing conditions (heavy corrosion around the connection), constraints around the area, etc, one foot of...
I was wondering how you design welds for shear flow along a built up girder (i.e. the flanges are welded to the web) with a distributed loading. Say you have a simple span with a uniform distributed loading, you shear would be a linear function of the location along the beam, with the greatest...
The buckles extend almost the entire height of the web, and buckle in plane (no twisting). They occur all along the length of the beam.
Yes, shear load seems fine, but is it possible to get this kind of buckled shape from bending? The flanges exibit no deformation.
Sizes:
The beam is a built up section, with an 84" (clear distance between flanges) deep web with a 0.4375" thickness. This is welded to plates that extend very far in either direction, with other webs down the line, so when analyzing these as a flange width, i used the formula...