Hey everyone
For building h<160ft, does anyone have a good example of what constitutes a porous vs non-porous parapet for C&C loading? What type of parapet would you apply +/-GCpi = 0.18 or 0.55? I can see how a CMU wall or tilt wall may have GCpi=0. What about metal stud parapet?
Most examples...
A question about concrete sway frame: (correct me where I’m wrong)
When designing the columns, ACI allows us to use 3 methods – (a) Nonlinear 2nd order analysis; (b) Elastic 2nd order analysis or (c) Moment magnification.
In strength design of the columns and beams for wind controlled building...
Hi Everyone
We are field welding a HSS2x2x1/4 to a HSS8x8x1/4, flat part of HSS8x8 only. The AISC manual shows the "Effective Throat" for flare groove in Table J2.2. If we use 5/8R where R=2t, this becomes 5/8*2*(1/4)=5/16". This is the "effective throat". However, the weld strength based on...
ACI states that a drop panel dimension should be L/6 in both directions. Is this required if the drop panel is being considered for punching only, not for flexural design (say when a two way slab has shearwalls)? Has anyone ever taken this approach?
Hi Everyone
I am having a problem with a roof deck not attaching to some edge beams. I have tried to delete and reestablish the deck and beams a few different ways. It appears as if the beams are 'grayed' out at the location where the deck cannot 'attach' - the deck load is not being distributed...
Looking at the 9-Pile example in CRSI (2002), the author specs a Pu=1233 kip and suggests using a 50 ton/pile cap. The table shows a capacity of Pu=1376 kip, but 50 tons x 9 piles = 450 tons= 900 kip which is (obviously) less than 1233 kip. I thought the pile capacity had to match or exceed the...
Hey, everyone
We use Ram Concept for PT design. In a PT/Podium project, we typically balance 100-125% of the dead load because of the upper floors weighing down on the slab. When looking at the output, the slab deflections, moments..etc.. look ok. However, when we look at the Design...
For rebar (say #4 or #5 bar) being used as a shear dowel for concrete floor deck, are the equations for shear capacity the same as anchor bolts? This is being used to transfer diaphragm forces to cmu shear wall. I attached a pic I found online. Thanks
Hey, fellow engineers
I am setting up a Ram Elements project with concrete columns and walls supporting a concrete PT slab. I have set up the columns and walls (materials, thickness etc..in Elements) I need to know how to set up the PT slab in Elements in order to transfer it and design it in...
Hey everyone
We are working on an improvement project in an old Chicago building. The structure dates back to 1897. The 1st floor is old clay tile and steel floor system over a basement. I am trying to find out what the design loads may have been and how to determine the capacity of this type of...
Hi, everyone
Attached is a floor plan of a 2story wood frame home. I need to transfer the 2nd floor shear wall (dashed line) to the 1st floor wall to the left and below (garage opening line). I plan on using the floor trusses to act as 'drag struts' where shown.
What I assume I can do is use...
Hello, all
Please refer to the attached plan and section. My question is:1- When using a drag strut to transfer wind load to an interior shearwall, should the sheathing of the interior SW go up to the ceiling diaphragm (in red) or could it stay at ceiling elevation?
2-Also, should there be any...
I am designing the exact weld shown on Pg 8-61 of 13ed of AISC manual. The load is a torsion of a HSS8x4x1/4, and I need to design the top weld for tension. From what I understand, equation Rn=0.6*F(EXX)*.7071*(D/16)*l is only for fillet welds. Anyone know what the tension weld strength equation...
I am designing a small CMU building (only 1200sf). The proposed roof by contractor will be cold formed Zee or Cee purlin joists with 1.5F 20Ga Vulcraft deck. I know that deck selected is ok for diaphragm loads, but is using Z or C cold formed shapes ok for this application? I've only used steel...
Does anyone have a resource with wood frame design example? Specifically, I am looking at a design example of a wood stud, rafter, ridge beam etc... to compare with the output of my structural software.
I know there is a good number of software, but verifying and ensuring you are using it...
I am designing a 50x262 icf building with cold formed/metal deck roof. Because the high aspect ratio of 5.24:1, we want to use some of the interior metal stud walls as shear walls.
Two questions are: Is this aspect ratio indeed too high to span the entire length without the interior shearwalls...
I have designed a couple of ICF homes with 8-10ft plate height where prescriptive design is allowed. However we are being approached about a commercial building with wall heights of 15-20ft. We are probably going to use flat wall. My question is what ACI method is most commonly used? Empirical...
