wallache:
So 1300 psi gives me 97% stress in bending, which leads me to believe that 1300 psi was used. With 1500 psi, demand capacity ratio (DCR) is 85%. As a side note, no issue in shear.
jayrod12:
I haven't seen much residual capacity in my area, especially in tilt-up warehouse building...
Hi everyone,
I have an old as-built drawing that shows the bending stresses, but it is worded differently than how it is worded now so if anyone can chime in based on his or her experience, it would be much appreciated. See the attached image for your reference.
In today's standard per NDS...
I have a project where the property line is very tight and the owner wants to capture the basement square footage as much as possible. This basement is locked by the soil in all four sides with one side having a ramp as a parking garage. Depending on the temporary shoring required and thickness...
Thanks guys!
Because Sms = Fa x Ss and Fa cannot be less than 1.2 if default site class D is selected per Section 11.4.3, it puts a penalty on the Sds. It is making all the sense now.
Down in Orange County, specifically in Irvine, there wasn't any increase. Up in Oakland, it went up almost...
Silly me.. It says Section 11.4.3.
Can anyone explain this section and the difference?
I have a project in Oakland and the difference in SDS is 1.9g for Default Site Class D and 1.6g for Site Class D.
Hi guys,
Do you guys understand the difference between Default Site Class D vs. Site Class D?
I went to SK Ghosh seminar and I believe Default Site Class D should be used if I do not have any soils report.
I am not sure where in the code this is stated.
Any thoughts?
Hi guys,
The geotechnical report is asking to use 4000 psi concrete due to moderate sulfate exposure. I will specify 4000 psi for footings but what about the stem of the CMU retaining wall?
I want to use CMU retaining wall (fully grouted). If so, does CMU block need to be protected from...
Fellow engineers,
I am in Southern California and almost every job site (residential) I have been to, the contractors do not install plywood sheathing for the entire exterior wall.
Rather, they only install where we call out wood shear walls.
I am curious from architectural and building...
Fellow engineers,
I am running into a problem in the field where beam penetrations through my steel beams need to occur. Our detail shows that the depth of the penetration can be D/3 (D = depth of steel beam) and the length of the penetration is 3/4*D.
This rectangular penetration has fillet...
Fellow structural engineers!
I have a residential custom home that requires a topping slab to accommodate the drainage system. Between the interior and exterior space, I am dropping the composite steel decking by 4" and allowing them to add a topping slab to slope to drain.
I am faced with a...
I have alway seen 2x14 being notched for wood stair. Can you notch a 4x wood stringer to fit the risers and treads??
I would appreciate any thoughts / concerns.
Never heard of this before. I don't think is the industry practice. Stiffness modifiers specified in ACI 318 reduces it. Are you saying that the paper / research states that reinforcements actually do not reduce the stiffness of beam, column, slab, wall, etc.?
Thanks for the response Mike. If you can expand on when you used it in the past, it would be so helpful. Is it strictly based on the fire rating and the limitations set by the architect in terms of floor assembly and ceiling space?
Have you guys used B-deck 1.5" + 2.5" LWC assembly before? I am designing a residential steel building and I am considering using B-deck instead of W3 or W2.
My past experiences with office buildings, we always used W2 or W3 deck for 2 hour fire ratings. For residential, I believe our building...
When it comes to figuring out the unbraced length of the chords, what do you guys use?
Currently, I have my unbraced length in weak-axis (call it yy) as 5 ft and in strong-axis (call it zz) as 55 ft. Now, because I am assuming that there is no bracing point vertically (in strong axis...
Thank you for your recommendations. I didn't expect to have such great discussions among everyone here. I am going to try to digest all of the suggestions above and keep you posted.
KootK:
1) Where on the span is the point load located? 50 ft span and point load is at 40 ft. (we have 10 feet on the other side (2 bays) that can fit 2 diagonals to reach to the support at the right)
2) Is the point load located at a panel point as one would expect? It is located at where...
rapt: I am getting expected axial loads at both top and bottom chords. With the depth 5 feet deep and each Bay 5 ft wide, my diagonals are pinned at 45 degrees, which is an ideal angle. So yes, all of the axial load dumps into the diagonal and goes straight back to the support since the load is...
