Force around an opening
Force around an opening
(OP)
Folks,
I have a situation for which I need a creative solution. What you see in the attachment is a leg of a tilt up panel, through which the owner needs to run a 10" dia. pipe for stormwater.
I am required to evaluate if he can do it, meaning provide some alternate way to transfer the forces around the opening and then down the foundation.
Does anyone have a similar experience?
Thanks
I have a situation for which I need a creative solution. What you see in the attachment is a leg of a tilt up panel, through which the owner needs to run a 10" dia. pipe for stormwater.
I am required to evaluate if he can do it, meaning provide some alternate way to transfer the forces around the opening and then down the foundation.
Does anyone have a similar experience?
Thanks






RE: Force around an opening
DaveAtkins
RE: Force around an opening
Thanks for the suggestion. I am trying to get some more understanding of how the force flow is achieved.
As in how does the force transfer from the concrete to the steel member, and then back into the concrete? I am essentially making up for the area of lost concrete, but how long does the member need to be/ how should it be connected and such?
RE: Force around an opening
The crushing strenght of the tube also needs to be considered for annular deflection. You can use mining tunnel pipe deflection formulae for this purpose.
Hope that helps!
Cheers,
YS
B.Eng (Carleton)
Working in New Zealand, thinking of my snow covered home...
RE: Force around an opening
RE: Force around an opening
From my tilt-up design experience, it just looks to me that there will be too much reinforcing required and too little structural space to utilize, especially considering shear reinforcing too. I can see two layers of #5 at 4 to 6" on center with ties, even if the hole is not there.
Mike McCann
MMC Engineering
RE: Force around an opening
RE: Force around an opening
Essentially you're treating the leg as a column. This has always been a point of annoyance for me: When is a tilt-up panel a wall, and when is it a column? I have never found a code that will draw a line between column vs. wall dimensions or aspect ratio, despite having looked for this guidance for a long time. I have always tried to treat any tilt up panel as a column if I believed the behaviour would be more likely to be column-like, or it it has a thickness to width ratio of less than 1/4.
And yes, the stirrups are for the shear capacity, but also for confinement. If you have a slender panel all around, then they are also to permit ductile plastic hinge formation at high seismic loads.
Cheers,
YS
B.Eng (Carleton)
Working in New Zealand, thinking of my snow covered home...