Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

RE: StructuralPedia - Main Wind Force vs C&C Wind Force

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Conrad,

It sounds like you might have a couple entries surrounding this topic (like what exactly a batten is?).

I would include something similar to what you start off with when you say " we don't really differentiate between MWFRS and C&C...". That alone is an interesting item that could be expanded on. Is that also true in Britain and Europe (Asia, Middle East, South America, etc.)? (See, I learned several things already. Now if there was only a place where I could write this stuff down that is searchable and have easy access to it...)

Different building elements are highlighted and how to handle them (walls, columns, beams, etc.) because I thought a designer would be looking to apply the MWF and C&C loading on an element by element basis. There are other elements that I didn't include that you may want to add. I don't have any code references to back up my statements other than the ones mentioned on this list, so anything that the code refers to about this topic is useful.

- Jeremy



Quoting Conrad Harrison <sch.tectonic(--nospam--at)bigpond.com>:

Jeremy,

How would I go about contrasting that with the local pressure factor
(kl)approach of AS1170.2, to add international context?

Here we don't really differentiate between MWFRS and C&C. Given the C&C
approach of ASCE7-05, and the research, there is an implication that maybe
we should probably be applying the local pressure factor in a lot more
situations. For example local pressure factor would be applied to roof
cladding and support batten, but not to any part of the roof truss nor
rafter. Nor to a wall stud. The validity of the approach is reinforced by
the timber framing code AS1684 and its accompanying structural model
AS1684.1. More over the truss or rafter and wall stud would be subject to an
area reduction factor (ka), and a load combination reduction factor (kc).
Most recent revisions to our code, seem to tend towards more ways of
reducing the wind loads not increasing. Maybe we should be tending towards
increasing loads.

On the other hand investigations after tropical cyclones tends to indicate
the code is providing adequate strength. The main changes have been improved
testing of steel cladding profiles for cyclonic conditions.

It seems our respective code authors have different philosophies regarding
risk, and accounting for extreme pressure coefficients: though neither of
our codes account for the Cp=-20 apparently recorded at Texas Tech full
scale building experiments.



Regards
Conrad Harrison
B.Tech (mfg & mech), MIIE, gradTIEAust
mailto:sch.tectonic(--nospam--at)bigpond.com
Adelaide
South Australia





******* ****** ******* ******** ******* ******* ******* ***
*   Read list FAQ at: http://www.seaint.org/list_FAQ.asp
*
*   This email was sent to you via Structural Engineers
*   Association of Southern California (SEAOSC) server. To
*   subscribe (no fee) or UnSubscribe, please go to:
*
*   http://www.seaint.org/sealist1.asp
*
*   Questions to seaint-ad(--nospam--at)seaint.org. Remember, any email you
*   send to the list is public domain and may be re-posted
*   without your permission. Make sure you visit our web
*   site at: http://www.seaint.org
******* ****** ****** ****** ******* ****** ****** ********




******* ****** ******* ******** ******* ******* ******* ***
*   Read list FAQ at: http://www.seaint.org/list_FAQ.asp
* * This email was sent to you via Structural Engineers * Association of Southern California (SEAOSC) server. To * subscribe (no fee) or UnSubscribe, please go to:
*
*   http://www.seaint.org/sealist1.asp
*
* Questions to seaint-ad(--nospam--at)seaint.org. Remember, any email you * send to the list is public domain and may be re-posted * without your permission. Make sure you visit our web * site at: http://www.seaint.org ******* ****** ****** ****** ******* ****** ****** ********