Great example Kestava!! Do you think you can continue this example with designing a strip footing (part 2 maybe) with the reinforcement details for this wall and show us a sketch for the reinforcement distribution along the wall and the footing? also can you show the reinforcement lap details between the CMU wall and the footing according to ACI maybe? That will be awesome!
Very nice video, thanks for sharing! I would be curious to know more about how you would calculate the load on the wall? In the example demonstrated in the video, it was given from the text. But in real life, how would you calculate the total load on the wall?
its all about the spans the wall is loading and the type of structure you are designing, aka whats the space being used for? assembly area? residential home? gym? office? the ASCE 7 / IBC give design criteria based on the use case. thats where it all comes from!
Great design example. Just one comment. Where you plug in the Pu in the masonry shear capacity, shouldn’t you use a load combination that gives you the list Pu (0.9D-0.2Sds) instead of the highest? I feel like the results won’t be conservative if you use what results in a higher axial load.
nothing this in depth, but parts of this could be, like the shear capacity equation may be something, and they would give you all the criteria needed to just plug and chug
shouldnt we ignore the shear capacity of concrete, when we are designing for seismic loads?.I think i read that in seismic provisions of chapter 18 of ACI318-19
This is a trick they like to use on the SE exam, they won't designate ordinary, intermediate or special in the problem statement but they will expect you to use the information given. I would reference chapter 12 of ASCE 7 to confirm which one is allowed given the building parameters and SDC. USUALLY if they don't say... the designation is special.
Yeah i wasn't sure which method I should have gone with, the example I was working through was strength design, but I believe its easier to design via ASD so ill confirm and most likely be doing that moving forward Jeff!
CMU are not great in seismic unless you can tie it down... CMU is also terrible for shear ... Hint: Make your sections solid and tied down... You have shit unless you tie -down is not done. Fully grouted just makes a vertical slab...again, you have to focus on the tie-down to the foundation.
absolutely! this was just a small sample of some of the steps in designing a CMU shear wall. we would absolutely need to design the tension hold down rebar at the ends of the walls and additional vertical rebar to even consider this as a shear wall. great point out!
Hey Rich great video bud, @8:51 found the equation to be 9-20 for TMS402-16
9-18 for TMS402-602
Thanks for posting this. I’m designing a cmu SW for a residential project. This was really helpful
Great example Kestava!!
Do you think you can continue this example with designing a strip footing (part 2 maybe) with the reinforcement details for this wall and show us a sketch for the reinforcement distribution along the wall and the footing? also can you show the reinforcement lap details between the CMU wall and the footing according to ACI maybe?
That will be awesome!
Vote up
Very nice video, thanks for sharing! I would be curious to know more about how you would calculate the load on the wall? In the example demonstrated in the video, it was given from the text. But in real life, how would you calculate the total load on the wall?
its all about the spans the wall is loading and the type of structure you are designing, aka whats the space being used for? assembly area? residential home? gym? office? the ASCE 7 / IBC give design criteria based on the use case. thats where it all comes from!
@@Kestava_Engineering Makes sense! And given the geometry and spans, do you calculate the tributary area to derive the load the wall is subjected to?
How to check special boundary element requirement for CMU shear wall. Let us know if you have any video.
Great design example. Just one comment. Where you plug in the Pu in the masonry shear capacity, shouldn’t you use a load combination that gives you the list Pu (0.9D-0.2Sds) instead of the highest? I feel like the results won’t be conservative if you use what results in a higher axial load.
I noticed this too. I believe you are correct.
Thanks for the video. Will this type/difficulty cmu wall design problem be expected on PE structural exam?
nothing this in depth, but parts of this could be, like the shear capacity equation may be something, and they would give you all the criteria needed to just plug and chug
@@Kestava_Engineering Thanks for sharing the idea. As always, your video helps me A lot. Two thumbs up 👍🏻
Why is an 8-inch wall actually 7.63 inches wide?
shouldnt we ignore the shear capacity of concrete, when we are designing for seismic loads?.I think i read that in seismic provisions of chapter 18 of ACI318-19
Great example! Would this be considered special reinforced masonry shear wall?
I would have to check all the requirements to consider special reinforced per the TMS but this should be most of the way there
This is a trick they like to use on the SE exam, they won't designate ordinary, intermediate or special in the problem statement but they will expect you to use the information given. I would reference chapter 12 of ASCE 7 to confirm which one is allowed given the building parameters and SDC. USUALLY if they don't say... the designation is special.
I’m also new to CMU design, I believe CMU is typically in ASD but I could be wrong?
Yeah i wasn't sure which method I should have gone with, the example I was working through was strength design, but I believe its easier to design via ASD so ill confirm and most likely be doing that moving forward Jeff!
I wish you would have shown where in the TMS402/602 you find the equations that you used.
ill be doing more of this moving forward! i think the most helpful thing is going through the code. thanks for your feedback!
Where is the max spacing around 13:00 from? I can't find it in TMS
7.3.2.6 (b) TMS 402-2016
When you calculated Pu, why didn't you also include the live load of 300 plf?
The live load does need to be considered since the load combination we are designing for is actually 1.2 D + 1.0 E + L + 0.2 S.
@@bikalshakya Why is it not included despite being in the load combination you stated?
CMU are not great in seismic unless you can tie it down...
CMU is also terrible for shear ... Hint: Make your sections solid and tied down...
You have shit unless you tie -down is not done.
Fully grouted just makes a vertical slab...again, you have to focus on the tie-down to the foundation.
absolutely! this was just a small sample of some of the steps in designing a CMU shear wall. we would absolutely need to design the tension hold down rebar at the ends of the walls and additional vertical rebar to even consider this as a shear wall. great point out!
How to calculate the vertical load on the wall?