I am trying to calculate the deflection of larger wood diaphragm of an existing building to check the seismic separation. I used SDPWS Eq 4.2-1 to calculate the diaphragm deflection using my pseudo static shear force. However, using ASCE 41-17, I am coming up with almost 2x the deflection I...
How does one determine the C&C wind load on walls of an open building? ASCE 7-16 Section 30.7 details how to calculate C&C loads on roofs, but not walls. Am I missing something?
I have attached a copy of our detail and the shop drawing detail.https://files.engineering.com/getfile.aspx?folder=3adb5a40-1419-495c-89f8-02f69b965773&file=Ftg_Ties_Rebar_Shop_Drawings.JPG
I am reviewing some rebar shop drawings for a project and have a question regarding the footing ties. On our drawings, we have a 10'-0" wide grade beam and we are showing continuous multi-ties with 6 vert legs. However, on the rebar shop drawings, they are not using continuous multi-ties. They...
I am reviewing a mix design for lightweight concrete to be used over metal deck and also as a polished slab. We specified a 3000 psi mix with a max w/c = 0.45 and a slump of 4". The proposed mix design has a w/c = 0.42, but the slump is listed as 8" +/- 2". Is this slump common for lightweight...
In my original design, I only checked the column using the amplified seismic load based on the mechanism analysis. As I understand it, I do not need to check the columns for an Omega load as the planchecker suggested. Is this correct?
I am working on a plancheck for a SCBF design I did and have a question about column design forces. I designed my columns based on forces developed from a mechanism analysis per AISC 341-10 Section F2.3(I) and F2.3(II). However, I received this plancheck comment:
"Column Designs: Axial load...
I am working on a 3-story moment frame building. It is 6 bays wide and has a 2 bay and a 3 bay moment frame connected by a simple supported beam.
I know the simple supported beam is a collector. But are the moment frame beams collectors? If so, I would need to design them with overstrength...
What is the best method to determine the uplift wind load on a horizontal sunshade (ASCE 7-10)? The sunshade protrudes about 3.5' from the side of the building.
My thought is to use Components & Cladding for a Gable Roof Overhang (< 7 deg). Do you agree?
Thanks!
I am working on a new 3-story woodframe project where the architect wants to use staggered stud walls for the exterior walls and corridor walls.
The exterior would be a 2x6 and a 2x4 staggered on a 2x8 plate. The corridor will probably be a 2x4 and a 2x4 on a 2x6 plate. Has anyone used...
I have a project in construction where I specified 3/4” of camber for a 44’ long W12x65 beam. The steel fabricator forgot to camber the beam and installed all of the stiffener plates (7 locations along its length). Then they cambered the beam.
They flange buckled locally at one location. A...
I reread 1616A.1.16 and realized I missed that the foundations need to be designed for the lesser of the three options as well. But this applies only to the concrete/reinf of the foundations, correct? The bearing pressures and mircropile friction can be sized using ordinary level forces, correct?
Unfortunately, it is DSA as this is a school building. It looks likes CBC 1616A.1.16 adds a section that requires the superstructure to foundation connection be designed for the strength of the system or overstrength forces. However, I do not see anything additional regarding the foundation design.
I am working on the foundation design of a 3-story special concentric braced frame building in California. The bedrock is very shallow at the site, so the grade beams will bear on bedrock. The geotechnical engineer recommends that I use micropiles or rock anchors to resist uplift loads. My...
Thanks for the replies. I am going to specify continuous 8" studs with wind girts at 15' and 32' to match the floor and low roof for the rest of the building. And I will provide an option to splice the studs just above the wind girts.
Thanks for the help!
I am working on the design of a theater building. The building will be steel construction with concrete over metal floors and roof. The exterior walls will be non-bearing metal studs with cement plaster finish. The lateral system will be braced frames set inside the exterior walls.
At one area...
Thanks for the feedback!
I didn't like the idea of putting the curtain wall in the plane of the moment frames and you all seem to agree. I will push back on this.
Thanks for the AISC Design Guide link. I had not seen that.
Thanks for all of the help!
