I have an elevated concrete platform and I am researching on performing a time history analysis for the structure. The equipment manufacturer has provided a set of dynamic loads at the rotor support points for both horizontal and vertical directions. I have assigned sine functions for vertical...
I have an elevated concrete platform modeled in RISA 3D and I am researching on performing a time history analysis for the structure. The equipment manufacturer has provided a set of dynamic loads at the rotor support points for both horizontal and vertical directions. I have assigned sine...
Hey Guys,
I have got a quick question on loose lintels. When designing a loose lintel we assume the loose lintel to be braced at the end points. I am curious as to how this is assumed. I came up with the following arrangements,
1. If the vertical leg is against the sheathing, is it...
Hey guys,
I am working on a project with Intermediate Moment frames as the Main lateral force resisting system. Is there any prequalified moment connection that connects to the column web? I did not see any details in AISC Seismic Design Manual. Is this allowed?
When designing a steel moment frame, if the beam is designed to support the full gravity load as a simply supported beam and the connection is designed for moment due to wind only (instead of envelope combinations including Dead and Live), how does this affect the drift? Do we have to check the...
I have a steel structure building with first floor two way structural slab. The columns plinths are fairly large (40" diameter) and we need to leave block-outs for steel columns.The blockouts would be about 28" in diameter so we have about 6" of slab bearing around the plinth. The critical...
Quick question for the California Structural Engineers. Do jurisdictions in California require the SEOR to design the Steel connections or can it also be delegated to the fabricators connection engineer as mentioned in AISC?
Also, do you all (the SEOR's) in California typically design your...
Has anyone modeled wood shear walls under rigid or semi rigid diaphragms in RAM structural system?
I know you could model it using the "Other" material in RAM but what properties of the wood shear wall would most accurately capture the behavior. I have a 2x6 width wall. You can specify the wall...
I have a building which has a vertical combination of seismic force resisting system. The lower structure has a R=3.25 and upper structure has R=5.
Per 12.2.3.1 (ASCE 7-10), the R value for upper can be used for the upper portion and R value for lower can be used for the lower portion. The...
In Hilti Profis, the process of calculating shear capacity for anchors sitting on grout follows ETAG 001 Annex C (European guideline- Considers flexure in Anchor). While section D.6.1.3 Appendix D of ACI 318-11 just requires the shear capacity to be multiplied with 0.8 when a grout pad is used...
I am working on a Hotel project which has a 1 story steel podium (Non-composite slab) and 4 stories of wood above it located in California (Seismic Controlling).
We have masonry shear walls in the building which we want to use as our main LFRS. I have a few concerns about this structure:
1. If...
Hi all,
We are having a discussion in the office regarding a particular cantilever connection detail and wanted to get more input on it.
The attached detail shows a cantilever beam with a back span connected to a column (This happens on two sides so that it is a cantilever frame). Does this...
I am working on a demolition and replacement of a concrete slab w/deck for a composite floor system. We are essentially removing the concrete slab along with the deck and all the shear studs.
We will be shoring and reusing the steel beams which will be installed with new studs and new concrete...
I have modeled the same building (Which is a Concrete structure) in ETABS and RAM with the exact same loading. However the dead load reaction seems to vary by as much as 20% between the two programs (Used results from RAM Frame). While I have not checked the live load reaction, I was expecting...
I have a building model in ETABS with 8 parking floors and 15 apartment floors on top. When I run the analysis and design for the structure, the columns near the ramps of the parking floors are giving out an error saying that " Factored axial load is greater than the Euler load".
I am positive...
Hello friends,
I am modelling a building in ETABS (V 9.2), and this is my first time using the software. I have already gone through the Tutorial and the reference manuals.
I have a question about modelling loads of different magnitudes on the floor.
To start, ETABS lets you input area loads...
