Could you use a concrete beam to span over the conduits with a void form between the beam and conduits? The beam could span between 2 footings and could be at or below the slab elevation?
-MMARLOW EIT
Woody,
In the Northeast, SPF is the most common lumber for wood framing. However, PT lumber is typically Southern Pine. I have typically seen PT framing called out as "P.T. 2X10" on the plans and in the general notes or specifications the requirements for PT lumber is defined
Hope that helps...
Duggerdoo,
I typed rafter tie when I should have typed collare tie.. but yes.
In typical wood framed construction the ridge plate is supported by the rafters when there are collar ties. I dont know why that wide flange beam at the ridge would need to be there. The collar ties will need to be...
Duggerdoo,
You said lower 3rd previously.
The rafters do not support the ridge in your sketch. The pitch does not matter.
You are correct, it is a simple question. A FBD gets you to the answer quite quickly.
-MMARLOW EIT
Duggerdoo,
Understood. Your sketch didnt show a tie and a free body diagram would have gotten you to the point that a tie would be required.
If there is a tie, id refer to it as a ridge plate and it is supported by the rafters.
If you have no tie, you need a ridge beam supported at its ends...
Im currently in my last course of the online MCE-structures program at Norwhoch University.
I went to Umass Amherst for undergrad, and stayed in touch with a few classmates who stayed there to finish their masters. Below are the differences that I picked up based on our conversations.
-There...
ASCE has a wind guide. Its full of examples of both procedures. I found it helpful.
I had free access to it at the school library in grad school. I would say it is worth the purchase for a young engineer.
Wind Loads: Guide to the Wind Load Provisions of ASCE 7-10
However, as stated before...
If you are referring to a concrete slab. I tend to do what you are saying, or I do a 12" section and get an equivalent reinforcement ratio. The only issue with this, as far as I can tell, is that when you are making an equivalent amount if rienforcing, if you use smaller bars they will develop...
Ideem,
Thank you for your input. Im using ACI 318-14.
I actually get quite a but of capacity out of the reinforced member:
f'c = 5*sqrt(3000) = 274psi
sx = (24*60^2)/6 = 14400 in^3
phi*Mn= 0.6 * 274 * 14400 *1/(12*1000) = 197k-ft
I'll look into that beam idea if we get to that point...
Hello,
I have a project where a customer wishes to tear down and existing boat house and build a new one on its foundation. With limited information we are assuming that the concrete foundations have the same width at the bottom as they do the top (2'-0") and that it is reinforced.
We know the...
Winelandv,
Thank you for the response. I have used load sharing before, but in this case I have end posts with pinned top connections that will not be able to transfer any load over to the other posts. This might work for center posts that have adjacent posts on either side, as the pin top rail...
Hello,
I'm sure someone has posted about this before, but I'm having trouble finding it.
I'm designing a temporary construction platform out of wood. The contractor is proposing 2X4 posts at 4' O/C (in the weak direction). I've seen this on construction sites before, but am unable to get this...
Hello,
Im in the process of analyzing an existing Joist Girder for the loads of new RTU's. The Web members are double angles and are 20-30% over stressed. Which does seem strange because the chord members appear adequate.
These web members have no intermediate connectors. Is it reasonable to...
There might be some concerns with welding and vibrations? Look into fatigue loading. You're loads are really low, so it might not be too big of an issue. Im not really understanding your issue with KootK's HSS approach? Why split up the dead load?
-MMARLOW EIT
