Structural Engineering: 2009-10-04

Saturday, October 10, 2009

Re: QUESTION REGARDING 18B40 (LIGHT BEAM SECTION PROPERTIES)

Just to add to the confusion, Canada had one steel mill (Algoma Steel) producing wide flange shapes from the 60's through the early 2000's.
They produced a W18x40 which had a depth of 17.74", width of 7.44", flg t of 0.44" and web t of 0.3". It was made in our 44W (Fy =44ksi) steel. To avoid confusion with the American W18x40 it was changed to a W18x41, in 1978 I believe. It was never listed in the AISC steel manual but some American manufacturers (& the odd European mill) picked up those different Canadian shapes up after Algoma got out of the wide flange business in 200X.
Gary

Harold Sprague wrote:

Katy,
You are going to have to measure the shapes in the field.

Richard,
The AISC data base is for shapes currently constructed and contained in the AISC 13th Edition. Katy indicated that this was constructed in 1970.

Katy,
The AISC 6th Edition was in force from 1963 to 1970 when the AISC 7th Edition came out. The convention of listing the depth and then the weight per foot was established before the 1950's. In the 1950's the convention was to call out the depth, shape, and weight per foot (example 14 WF 43). Plan steel shape designation was formalized in the AISC 7th Edition, p 1-10. The example cited in the AISC 7th Edition is the "New Designation W14x26... Old Designation 14B26". The practice was to list the depth in inches followed by the weight in pounds per foot. Bethlehem listed designations in their 1940's literature with "B" and the AISC designations were "WF". Later, AISC changed formalized the designation to for all member mills to "W".

I worked for a steel fabricator, erector and detailer from the mid 1970's until 1980. The company dated back to 1927. The engineer for whom I worked started his career in 1950. He taught me the old call outs as well as the new ones.

According to the AISC "Historical Record....", the shapes with a depth of 18 inches had a minimum weight of about 46 pounds per foot through the early 1950's. The AISC 7th Edition shows a W18x40. The W18x40 and W18x35 are the same family and first came onto the market somewhere in the 1960's. Per the AISC 7th Edition, the 3 mills that manufactured the W18's were Bethlehem, Inland, and US Steel. The only manufacture making this particular family of W18's of which I am aware was Bethlehem in the early 1960's according to the US Steel and Bethlehem product literature.

If the beam measures 18 inches in depth, has a 6 inch wide flange, a 1/2" thick flange, and the call out is somewhat correct, it is most likely a W18x40 manufactured by Bethlehem Steel.

Regards, Harold Sprague

From: RichardC@lbbe.com
To: seaint@seaint.org
Date: Fri, 9 Oct 2009 07:12:10 -0400
Subject: RE: QUESTION REGARDING 18B40 (LIGHT BEAM SECTION PROPERTIES)

Please look at

http://www.aisc.org/content.aspx?id=21908

If you're a member you can download the DB for free – I have it, but the file is likely too large to go thru the email…

and no, that isn't necessarily a W18x40 – some time ago different manufacturers used differing nomenclatures. I have an old 193x Carnegie steel book that uses similar nomenclature to this (I don't have access to it ATM) but following their nomenclature that section may well be a 40" deep by 18" wide section. And I believe they used B as well for wide flanges.

Best to get the full (mostly) DB from AISC to be certain.

From: Harold Sprague [mailto:spraguehope@hotmail.com]
Sent: Thursday, October 08, 2009 10:06 PM
To: seaint@seaint.org
Subject: RE: QUESTION REGARDING 18B40 (LIGHT BEAM SECTION PROPERTIES)

If it was built in 1970, it was a W18x40. The engineer was probably an old timer. The B was indicative of a Bethlehem beam.

Check out the references:
http://www.slideruleera.net/miscellaneous.html

Regards, Harold Sprague

> Date: Thu, 8 Oct 2009 16:49:29 -0700
> From: katy6827@cox.net
> To: seaint@seaint.org
> Subject: QUESTION REGARDING 18B40 (LIGHT BEAM SECTION PROPERTIES)
>
> I have an existing structure built in 1970 and the structural drawing calls out a 18B40 beam section. My AISC Steel Manual 6th Edition does not have the beam section listed under the "light beam" section and neither does the WF section. I was not able to find it in the AISC Historic Shapes database either. When comparing other shapes it appears as if the section properties of a W18x40 would be similar.
>
> Does anyone know where I can find information on a 18B40 beam section?
>
> Thanks,
> Katy
>
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Friday, October 9, 2009

PSSDB system

I am searching to get some material about the PSSDB system which stands for "profiled steel sheet dry borad". I wonder if you introduce me some website which contains that information. the area that i'm interested in is the contact between the concrete and profiled steel sheeting in composite slab. and also about the optimization of the profiled steel section.

Regards

--
Mahmood Seraji
H/P: +60-17-319-5820

StructuralPedia - Cofar Composite Slab

For any of the historical structural systems experts, I started an entry for Cofar slabs if you would like to add to it.

http://structuralpedia.com/index.php?title=Cofar_Composite_Slab

- Jeremy

Re: California SE exam

Sid-

I recommend the 3 volume 2006 IBC Structural/Seismic Design Manuals
published by SEAOC. Though the design reference is also the IBC, not
the actual CBC, the design examples are very close to the flavor of the
day 2 test. Maybe the same people wrote both but that is just a guess
on my part. Make sure you have a current CBC with all errata and
amendments and double check the code references to the IBC with the
corresponding CBC section as you study. When I took it the CBC was not
IBC, rather UBC based but the word from recent test takers in my office
is that this is still the best resource for studying for and reference
during the exam.

Good luck... BTW the day 2 test is much harder IMO than day 1 so be
ready. Taking them separately is probably a good strategy; the back to
back 8 hour brain crushes isn't the greatest way to kick off a weekend.

Donny Harris, SE
Los Angeles, CA

I am preparing for California SE exam (Seismic portion only). I passed
the National portion in April which was based on IBC 06.

I have Seismic and Wind Forces Structural Design Examples 3rd edition by
Alan Williams,updated to IBC 2006.

Is there any similar guide/reference available with CBC 07 reference?

Thanks!

Sid

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RE: QUESTION REGARDING 18B40 (LIGHT BEAM SECTION PROPERTIES)

Katy,
You are going to have to measure the shapes in the field.

Richard,
The AISC data base is for shapes currently constructed and contained in the AISC 13th Edition. Katy indicated that this was constructed in 1970.

Katy,
The AISC 6th Edition was in force from 1963 to 1970 when the AISC 7th Edition came out. The convention of listing the depth and then the weight per foot was established before the 1950's. In the 1950's the convention was to call out the depth, shape, and weight per foot (example 14 WF 43). Plan steel shape designation was formalized in the AISC 7th Edition, p 1-10. The example cited in the AISC 7th Edition is the "New Designation W14x26... Old Designation 14B26". The practice was to list the depth in inches followed by the weight in pounds per foot. Bethlehem listed designations in their 1940's literature with "B" and the AISC designations were "WF". Later, AISC changed formalized the designation to for all member mills to "W".

I worked for a steel fabricator, erector and detailer from the mid 1970's until 1980. The company dated back to 1927. The engineer for whom I worked started his career in 1950. He taught me the old call outs as well as the new ones.

According to the AISC "Historical Record....", the shapes with a depth of 18 inches had a minimum weight of about 46 pounds per foot through the early 1950's. The AISC 7th Edition shows a W18x40. The W18x40 and W18x35 are the same family and first came onto the market somewhere in the 1960's. Per the AISC 7th Edition, the 3 mills that manufactured the W18's were Bethlehem, Inland, and US Steel. The only manufacture making this particular family of W18's of which I am aware was Bethlehem in the early 1960's according to the US Steel and Bethlehem product literature.

If the beam measures 18 inches in depth, has a 6 inch wide flange, a 1/2" thick flange, and the call out is somewhat correct, it is most likely a W18x40 manufactured by Bethlehem Steel.

Regards, Harold Sprague

From: RichardC@lbbe.com
To: seaint@seaint.org
Date: Fri, 9 Oct 2009 07:12:10 -0400
Subject: RE: QUESTION REGARDING 18B40 (LIGHT BEAM SECTION PROPERTIES)

Please look at

http://www.aisc.org/content.aspx?id=21908

If you're a member you can download the DB for free – I have it, but the file is likely too large to go thru the email…

and no, that isn't necessarily a W18x40 – some time ago different manufacturers used differing nomenclatures. I have an old 193x Carnegie steel book that uses similar nomenclature to this (I don't have access to it ATM) but following their nomenclature that section may well be a 40" deep by 18" wide section. And I believe they used B as well for wide flanges.

Best to get the full (mostly) DB from AISC to be certain.

From: Harold Sprague [mailto:spraguehope@hotmail.com]
Sent: Thursday, October 08, 2009 10:06 PM
To: seaint@seaint.org
Subject: RE: QUESTION REGARDING 18B40 (LIGHT BEAM SECTION PROPERTIES)

If it was built in 1970, it was a W18x40. The engineer was probably an old timer. The B was indicative of a Bethlehem beam.

Check out the references:
http://www.slideruleera.net/miscellaneous.html

Regards, Harold Sprague

> Date: Thu, 8 Oct 2009 16:49:29 -0700
> From: katy6827@cox.net
> To: seaint@seaint.org
> Subject: QUESTION REGARDING 18B40 (LIGHT BEAM SECTION PROPERTIES)
>
> I have an existing structure built in 1970 and the structural drawing calls out a 18B40 beam section. My AISC Steel Manual 6th Edition does not have the beam section listed under the "light beam" section and neither does the WF section. I was not able to find it in the AISC Historic Shapes database either. When comparing other shapes it appears as if the section properties of a W18x40 would be similar.
>
> Does anyone know where I can find information on a 18B40 beam section?
>
> Thanks,
> Katy
>
> ******* ****** ******* ******** ******* ******* ******* ***
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Re: California SE exam

Sid,

I agree with Scott's thoughts here. When I took and passed the SE a few years back, it was when they had just changed to the 8-hr NCEES exam on Friday, and had the CA state specific 8-hr exam on Saturday. As Scott mentioned, you have to know the footnotes and exceptions that are throughout the California Building Code as they apply to hospitals (OSHPD) and to public schools (DSA). Things like using a 2x sill plate where the shear exceeds 350 plf as long as plate washers are placed...

If you don't know where all those little footnotes are at, you will lose a lot of time searching for those things. The state specific portion was an absolute bear. To pass the exam, you must manage your time.

I was fried, dejected and deflated as I walked out of the testing hall. I was seriously considering a career change. But, here I am.

Good luck with the exam.

On Thu, Oct 8, 2009 at 10:51 PM, Scott Maxwell <smaxwell@umich.edu> wrote:

You threw for a loop with the "seismic only" bit. While I have no direct experience the the new or old California SE exams, I would expect the state specific exam for CA SE is similar to what Wasington does with the Srtuct III exam for their SE license, which I do have direct experience with. If so, while will be heavily dominated by seismic design, you likely will also need to know non-seismic stuff as well. To my knowledge, the only "pure" seismic only exam that I am aware of in CA is the one that is part of getting your PE exam.

If the state specific CA SE exam is like WA's, then you will want to be VERY familar with all materials (wood, masonry, concrete, and steel) for both seismic and non-seismic. It might have less wind design stuff than WA's exam, but I suspect you will still see some. If nothing else, you will see some wind design on the NCEES Struct II exam. And try to be as familiar as possible with where stuff is in the code(s) as these exams tend to have MAJOR time component...if you spend a lot of time looking stuff up to figure out how to do a problem, you are more than likely "toast".

HTH,

Scott
Adrian, MI

On Oct 8, 2009, at 8:05 PM, "Lakhani, Sid" <slakhani@ebmud.com> wrote:

Scott,

Thanks!

No, I already have PE.

This is a recent change. Few years ago one had to take 16 hour California test (CBC reference code)

Now it is required to pass 8 hour National (IBC reference code) test which includes general structural analysis and design; and 8 hour California Seismic (CBC reference code)

Sid

From: Scott Maxwell [mailto:smaxwell@umich.edu]
Sent: Thursday, October 08, 2009 3:49 PM
To: <seaint@seaint.org>
Subject: Re: California SE exam

Do you mean the Seismic exam for the CA PE or do you mean the state specific exam (which to my knowledge is NOT "seismic only" along though it will certainly cover seismic stuff) portion for your CA SE? Those are two COMPLETELY different animals.

Regards,

Scott

Adrian, MI

On Oct 8, 2009, at 4:42 PM, "Lakhani, Sid" <slakhani@ebmud.com> wrote:

I am preparing for California SE exam (Seismic portion only). I passed the National portion in April which was based on IBC 06.

I have Seismic and Wind Forces Structural Design Examples 3^rd edition by Alan Williams,updated to IBC 2006.

Is there any similar guide/reference available with CBC 07 reference?

Thanks!

Sid

--
David Topete, SE

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

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@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@bigpond.com
> Adelaide
> South Australia
>
>
>
>
>
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Re: StructuralPedia - Main Wind Force vs C&C Wind Force

Gary,

Thanks for the feedback!

- Jeremy

Quoting "Gary L. Hodgson and Assoc." <design@hodgsoneng.ca>:

> Jeremy,
> You might want highlight the "log in" a little better. It took me a
> couple of minutes to spot it, but that is the problem with old eyes.
> Gary
>
> Jeremy White wrote:
>> For anyone who may be interested I have summarized the Main Wind
>> Force vs C&C Wind Force discussion as an entry on StructuralPedia.
>>
>> http://structuralpedia.com/index.php?title=Main_Wind_Force_vs_C%26C_Wind_Force Feel free to add to it or modify it as
>> necessary.
>>
>> One question I came up with when creating this is: Can a pilaster
>> be part of a masonry shear wall? Are pilasters typically part of
>> the shear wall? Usually you put a joint on one or both sides of a
>> masonry pilaster which I wouldn't consider capable of transferring
>> shear force.
>>
>> - Jeremy
>>
>>
>> ******* ****** ******* ******** ******* ******* ******* ***
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Re: StructuralPedia - Main Wind Force vs C&C Wind Force

Jeremy,
You might want highlight the "log in" a little better. It took me a
couple of minutes to spot it, but that is the problem with old eyes.
Gary

Jeremy White wrote:
> For anyone who may be interested I have summarized the Main Wind Force
> vs C&C Wind Force discussion as an entry on StructuralPedia.
>
> http://structuralpedia.com/index.php?title=Main_Wind_Force_vs_C%26C_Wind_Force
>
>
> Feel free to add to it or modify it as necessary.
>
> One question I came up with when creating this is: Can a pilaster be
> part of a masonry shear wall? Are pilasters typically part of the
> shear wall? Usually you put a joint on one or both sides of a masonry
> pilaster which I wouldn't consider capable of transferring shear force.
>
> - Jeremy
>
>
> ******* ****** ******* ******** ******* ******* ******* ***
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> ** This email was sent to you via Structural Engineers*
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Re: my periodic leak rant

Chuck,
I agree with you completely. I have always thought that having houses
designed by engineers was a waste. Prescriptive design ( under 6400 sq
ft & 3 stories) seems to be good for 90% of the homes and small
buildings being built out here, that and regular inspections by the
municipality. I still get work on houses and small buildings because
some houses may have unusual designs, are out of the scope of the
prescriptive part of the code, or have long span beams or poor soil
conditions. But the big protection comes from being able to sue the
municipality or inspector which keeps them on their toes. Also there is
no where in Ontario you can build without municipal approval, except on
federal property and even they will notify the municipality as a courtesy.
Gary

Chuck Utzman wrote:
> Andrew
> Based on my 7 years of doing nothing but residential forensic work in
> the '90s in the San Francisco area I've concluded our construction
> priorities are upside down. In Marin Co. all structural analysis &
> design gets peer reviewed & final occupancy requires an Observation
> report from the EOR for excavation, rebar, structural framing, & LFRS.
> IMHO we could dispense with all of the above & replace it with
> compitent inspection of the building's waterproof envelope. Heck, we
> could fire all the structural engineers & come out way ahead if we
> just stopped the leaks.
> California is spending literally billions every year dealing with
> decay & the design community and Building Departments don't see to be
> at all concerned.
> Chuck Utzman
>
>>
>>
>>
>>
>
>
>
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RE: QUESTION REGARDING 18B40 (LIGHT BEAM SECTION PROPERTIES)

Please look at

http://www.aisc.org/content.aspx?id=21908

If you’re a member you can download the DB for free – I have it, but the file is likely too large to go thru the email…

and no, that isn’t necessarily a W18x40 – some time ago different manufacturers used differing nomenclatures. I have an old 193x Carnegie steel book that uses similar nomenclature to this (I don’t have access to it ATM) but following their nomenclature that section may well be a 40” deep by 18” wide section. And I believe they used B as well for wide flanges.

Best to get the full (mostly) DB from AISC to be certain.

Hotmail: Free, trusted and rich email service. Get it now.

Thursday, October 8, 2009

Re: California SE exam

You threw for a loop with the "seismic only" bit. While I have no direct experience the the new or old California SE exams, I would expect the state specific exam for CA SE is similar to what Wasington does with the Srtuct III exam for their SE license, which I do have direct experience with. If so, while will be heavily dominated by seismic design, you likely will also need to know non-seismic stuff as well. To my knowledge, the only "pure" seismic only exam that I am aware of in CA is the one that is part of getting your PE exam.

If the state specific CA SE exam is like WA's, then you will want to be VERY familar with all materials (wood, masonry, concrete, and steel) for both seismic and non-seismic. It might have less wind design stuff than WA's exam, but I suspect you will still see some. If nothing else, you will see some wind design on the NCEES Struct II exam. And try to be as familiar as possible with where stuff is in the code(s) as these exams tend to have MAJOR time component...if you spend a lot of time looking stuff up to figure out how to do a problem, you are more than likely "toast".

HTH,

Scott

Adrian, MI

On Oct 8, 2009, at 8:05 PM, "Lakhani, Sid" <slakhani@ebmud.com> wrote:

Scott,

Thanks!

No, I already have PE.

This is a recent change. Few years ago one had to take 16 hour California test (CBC reference code)

Now it is required to pass 8 hour National (IBC reference code) test which includes general structural analysis and design; and 8 hour California Seismic (CBC reference code)

Sid

From: Scott Maxwell [mailto:smaxwell@umich.edu]
Sent: Thursday, October 08, 2009 3:49 PM
To: <seaint@seaint.org>
Subject: Re: California SE exam

Do you mean the Seismic exam for the CA PE or do you mean the state specific exam (which to my knowledge is NOT "seismic only" along though it will certainly cover seismic stuff) portion for your CA SE? Those are two COMPLETELY different animals.

Regards,

Scott

Adrian, MI

On Oct 8, 2009, at 4:42 PM, "Lakhani, Sid" <slakhani@ebmud.com> wrote:

I am preparing for California SE exam (Seismic portion only). I passed the National portion in April which was based on IBC 06.

I have Seismic and Wind Forces Structural Design Examples 3^rd edition by Alan Williams,updated to IBC 2006.

Is there any similar guide/reference available with CBC 07 reference?

Thanks!

Sid

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

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@bigpond.com
Adelaide
South Australia

RE: QUESTION REGARDING 18B40 (LIGHT BEAM SECTION PROPERTIES)

Hotmail: Free, trusted and rich email service. Get it now.

StructuralPedia - Main Wind Force vs C&C Wind Force

For anyone who may be interested I have summarized the Main Wind Force
vs C&C Wind Force discussion as an entry on StructuralPedia.

http://structuralpedia.com/index.php?title=Main_Wind_Force_vs_C%26C_Wind_Force

Feel free to add to it or modify it as necessary.

One question I came up with when creating this is: Can a pilaster be
part of a masonry shear wall? Are pilasters typically part of the
shear wall? Usually you put a joint on one or both sides of a masonry
pilaster which I wouldn't consider capable of transferring shear force.

- Jeremy

Re: my periodic leak rant

I agree with the problems of leaks. Over the life of a wood structure, it may experience the design earthquake or high winds, but it will definitely experience water from leaks or moisture buildup from the interior. The lack of gutters, eaves, poor drainage on the ground around the house, absence of a vapor retarder affects more wood structures in Alaska than winds and earthquakes combined. There was a report on the radio a few weeks ago about the fire station in Bethel (rural western bush Alaska). The firemen are not allowed to stay in the building overnight. There was a structural inspection done recently and when they peeled back some of the gypsum wallboard to look at the decayed wood studs, the roof of the building settled a bit. When you're depending on gypsum wall board for structural safety, you have big problems.

Chuck Utzman wrote:

Andrew
Based on my 7 years of doing nothing but residential forensic work in the '90s in the San Francisco area I've concluded our construction priorities are upside down. In Marin Co. all structural analysis & design gets peer reviewed & final occupancy requires an Observation report from the EOR for excavation, rebar, structural framing, & LFRS.
IMHO we could dispense with all of the above & replace it with compitent inspection of the building's waterproof envelope. Heck, we could fire all the structural engineers & come out way ahead if we just stopped the leaks.
California is spending literally billions every year dealing with decay & the design community and Building Departments don't see to be at all concerned.
Chuck Utzman

akester@cfl.rr.com wrote:

Richard has it right with newer homes in FL, although my house was built in the 50s and older homes often are crawspace on CMU stem walls and piers with wood frame walls. I like the look of heavy timber such as in ski lodges, and in log cabins, so it has its place. I am about to do a back porch addition out of exposed wood rafters with a 1x tongue and groove ceiling/decking. In dry, western, seismically active regions, I see why timber may be used as a preferable material. But I am a CMU guy all the way for Florida for all the reasons others have stated: wind pressure, wind borne debris debris, uplift resistance, termites, and moisture and vapor control, thermal R values, sound, and moisture and rot damage. In new construction in S FL you barely see wood at all except for trusses and interior walls. I did a forensic job at a house in Miami with a steel joist and concrete floor system, I was amazed...

Since I have been doing a lot of forensics the last five years all over the state, a lot of the wood damage I have seen has made me a believer that it is an uphill battle in a sub tropical climate. Of course these things cannot be overlooked but usually are: sprinklers near buildings, the MUST of gutters and getting water away from buildings, proper and functional roof slope design (too many funky hips and valleys always creates problems), and flashing flashing flashing.... Just general smart architecture would help.

Did a job a while back at a house with moisture damage and roof issues. They were from Bosnia and also not impressed with our construction methods.
I think a lot of it has to do with the fast track nature of much of home construction during the bubble, especially in FL and probably in AZ, CA and other hot real estate market states. Big tract housing was thrown up at huge scales using untold numbers of subs who used unskilled immigrant workers (not their fault, just fact). The bottom line often wins out over quality. I got the same complaint from northerners/Yankees who pissed and moaned about how much better they did it up north. Maybe they have a point. But another dirty secret in the housing market, absent of a company like Richard's, is that many houses are not designed by professionals. I am not saying they are not signed and sealed by professionals, just not designed. It is the biggest off the shelf plan and copy and paste scam, and they can always find someone with a seal to rent. I know about if first hand, which is why I rarely did full residential jobs, and never did neighborhoods. Sorry, I will not just review and seal your drawings Residential Cad Design Inc. for $200.

I digress, sorry this was long winded. Go CMU and concrete! Wood, sorry, you have your place. My dream house in FL will use wood on the floors, cabinets, balconies, and maybe some of the roof. Also, I am a big fan of a safe room. Every room in 'cane country should just take a master walk in closet or something like that and make it a safe room. CMU with #5s @ 40" o.c., all solid grout, 4" slab ceiling. No windows, hardened or steel door. 12" thick mat foundation. Bring it on! Then just design the rest of your house to code or a little higher. To me, that is the best mix of safety and practicality and economics...

Andrew Kester, PE

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RE: California SE exam

Scott,

Thanks!

No, I already have PE.

This is a recent change. Few years ago one had to take 16 hour California test (CBC reference code)

Now it is required to pass 8 hour National (IBC reference code) test which includes general structural analysis and design; and 8 hour California Seismic (CBC reference code)

Sid

From: Scott Maxwell [mailto:smaxwell@umich.edu]
Sent: Thursday, October 08, 2009 3:49 PM
To: <seaint@seaint.org>
Subject: Re: California SE exam

Do you mean the Seismic exam for the CA PE or do you mean the state specific exam (which to my knowledge is NOT "seismic only" along though it will certainly cover seismic stuff) portion for your CA SE? Those are two COMPLETELY different animals.

Regards,

Scott

Adrian, MI

On Oct 8, 2009, at 4:42 PM, "Lakhani, Sid" <slakhani@ebmud.com> wrote:

I am preparing for California SE exam (Seismic portion only). I passed the National portion in April which was based on IBC 06.

I have Seismic and Wind Forces Structural Design Examples 3^rd edition by Alan Williams,updated to IBC 2006.

Is there any similar guide/reference available with CBC 07 reference?

Thanks!

Sid

QUESTION REGARDING 18B40 (LIGHT BEAM SECTION PROPERTIES)

I have an existing structure built in 1970 and the structural drawing calls out a 18B40 beam section. My AISC Steel Manual 6th Edition does not have the beam section listed under the "light beam" section and neither does the WF section. I was not able to find it in the AISC Historic Shapes database either. When comparing other shapes it appears as if the section properties of a W18x40 would be similar.

Does anyone know where I can find information on a 18B40 beam section?

Thanks,
Katy

Re: FL construction

I would be careful that you are not mixing up general residential
construction quality with the use of specific materials. While the two
issues are kind of tied together, to me, your issue has more to do with
residential construction quality than type of material, per se.

You can design and build a perfectly good wood stick framed home...if it is
detailed properly for envelope issues and structural resistance to loads and
then build by a competent, quality construction company that does not place
"getting it out the door" over "doing it right". To me, in today's
residential construction world, there is WAY too much focus on the "fluff"
(i.e. The kitchen cabinet color, type of counter tops, whether or not the
appliances are stainless steel...both by the buyers and the home builders to
satisfy the buyers) and not enough on the "meat" (i.e. Building envelope
sealing issues, structural systems, etc) and this can result in some of the
"bones" of the home getting neglected during construction. Since wood stick
frame construction is the overwhelmingly predominate material of choice for
residential home construction in the US, this is why it is easy to associate
the poor construction issues with stick frame constructions...to me at a
least. Since masonry or reinforced concrete or steel construction is much
less common in residential construction, you have much better odds of
getting a contractor who is willing to do it right since no too many have
this area of "expertise" and thus, there are lot less "yahoos" out there who
do it for the "bottom-line buck" only and are more likely to to "get it
right".

This is a big reason why when I have looked at homes for myself, I tend to
look at older homes. Both of my houses that I have owned have been built in
the 50s. Some of the construction of "tract homes" that I have seen in the
90s and later just scares me in terms of quality.

The point is that I would argue you could certainly design a stick framed
home for Florida that would work just fine if you had an engineer and/or
architect detail it properly (including site issues such as NOT sloping the
ground toward the house) and a contractor who took the time to build it
correctly with quality in mind rather than just speed and bottom line cost.
But the reality is that most consumers do not know about or focus on that
type of stuff. They focus more on the "fluff" stuff such as stainless steel
appliances, granite countertops, the right paint color, the trophy master
bathroom, etc as all that other stuff is "greek" (so to speak).

Now, I do suspect that if you do detail such a home properly and get a
contractor to do it right, you will likely see a lot of the cost advantage
of the stick framed home disappear compared to a residential home in
masonry, reinforced concrete, and/or steel.

The end result is that if I ever build my "dream home", I will likely
consider masonry, steel, reinforced concrete, or some non-stick framed
construction as I would more likely be able to get a quality product, not
because they are inherently a better material. The problem with stick
framed construction is that there are just too many people out there doing
it that really should not be doing it as they do not care to do quality
work. This does not mean that you cannot get it done with quality, but more
that you will have a tougher time getting a contractor who does do quality
work.

Just my 2 cents.

Regards,

Scott
Adrian, MI

On 10/8/09 4:23 PM, "akester@cfl.rr.com" <akester@cfl.rr.com> wrote:

> Richard has it right with newer homes in FL, although my house was built in
> the 50s and older homes often are crawspace on CMU stem walls and piers with
> wood frame walls. I like the look of heavy timber such as in ski lodges, and
> in log cabins, so it has its place. I am about to do a back porch addition out
> of exposed wood rafters with a 1x tongue and groove ceiling/decking. In dry,
> western, seismically active regions, I see why timber may be used as a
> preferable material. But I am a CMU guy all the way for Florida for all the
> reasons others have stated: wind pressure, wind borne debris debris, uplift
> resistance, termites, and moisture and vapor control, thermal R values, sound,
> and moisture and rot damage. In new construction in S FL you barely see wood
> at all except for trusses and interior walls. I did a forensic job at a house
> in Miami with a steel joist and concrete floor system, I was amazed...
>
> Since I have been doing a lot of forensics the last five years all over the
> state, a lot of the wood damage I have seen has made me a believer that it is
> an uphill battle in a sub tropical climate. Of course these things cannot be
> overlooked but usually are: sprinklers near buildings, the MUST of gutters and
> getting water away from buildings, proper and functional roof slope design
> (too many funky hips and valleys always creates problems), and flashing
> flashing flashing.... Just general smart architecture would help.
>
> Did a job a while back at a house with moisture damage and roof issues. They
> were from Bosnia and also not impressed with our construction methods.
>
> I think a lot of it has to do with the fast track nature of much of home
> construction during the bubble, especially in FL and probably in AZ, CA and
> other hot real estate market states. Big tract housing was thrown up at huge
> scales using untold numbers of subs who used unskilled immigrant workers (not
> their fault, just fact). The bottom line often wins out over quality. I got
> the same complaint from northerners/Yankees who pissed and moaned about how
> much better they did it up north. Maybe they have a point. But another dirty
> secret in the housing market, absent of a company like Richard's, is that many
> houses are not designed by professionals. I am not saying they are not signed
> and sealed by professionals, just not designed. It is the biggest off the
> shelf plan and copy and paste scam, and they can always find someone with a
> seal to rent. I know about if first hand, which is why I rarely did full
> residential jobs, and never did neighborhoods. Sorry, I will not just review
> and seal your drawings Residential Cad Design Inc. for $200.
>
> I digress, sorry this was long winded. Go CMU and concrete! Wood, sorry, you
> have your place. My dream house in FL will use wood on the floors, cabinets,
> balconies, and maybe some of the roof. Also, I am a big fan of a safe room.
> Every room in 'cane country should just take a master walk in closet or
> something like that and make it a safe room. CMU with #5s @ 40" o.c., all
> solid grout, 4" slab ceiling. No windows, hardened or steel door. 12" thick
> mat foundation. Bring it on! Then just design the rest of your house to code
> or a little higher. To me, that is the best mix of safety and practicality and
> economics...
>
> Andrew Kester, PE
>
>
>
>
> ******* ****** ******* ******** ******* ******* ******* ***
> * 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:
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> * send to the list is public domain and may be re-posted
> * without your permission. Make sure you visit our web
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>

Re: "antiquated" floor systems

I would argue the use of wood stick frame construction in the US and
Canadian is largely driven by economics...i.e. The fact that we have HUGE
expanses of forests that are ripe for making relatively cheap building
materials compared to steel, concrete, and masonry...at least for
residential construction.

Regards,

Scott
Adrian, MI

On 10/7/09 8:04 AM, "Gary L. Hodgson and Assoc." <design@hodgsoneng.ca>
wrote:

> I watch a lot of these home programs (my wife's choice most of the time)
> and several show European construction; and I have been over there
> also. The British use a lot of solid masonry, the French and Italians
> seem to use a lot of natural stone and the Germans seem to use stone and
> clay tile. So there is small wonder their homes last hundreds of
> years. A polish friend commented on the "poor" quality of Canadian
> construction, i.e, wood frame const. I guess you get what you pay for.
> Gary
>
> Stuart, Matthew wrote:
>> Andrew,
>>
>> Thanks for your additional insights into the world outside of the continental
>> US.
>>
>> ________________________________
>>
>> From: akester@cfl.rr.com [mailto:akester@cfl.rr.com]
>> Sent: Tue 10/6/2009 6:05 PM
>> To: seaint@seaint.org
>> Subject: re: "antiquated" floor systems
>>
>>
>>
>> Mathew,
>> I thought the same thing that Julio said when I saw one of your articles on
>> those types of floor systems. My ex was from Spain and her dad is an
>> architect and contractor. I was lucky to go there many times (Tenerife, one
>> of the Canary Islands), and they use this system almost exclusively in every
>> home. They also use peculiar though impressive things such as large pad
>> footings, pre-fab rebar columns, and reinforced concrete beams- in HOUSES...
>>
>> Several reasons that I could come up with. First, wood and steel are imported
>> and the former used mostly as decoration in balconies and doors. However,
>> they sit on quite a pile of volcanic rock. Second, they go multi-story due to
>> land value and the cost of building in mountainous terrain, so a good floor
>> system is imperative. Finally, you get a great, stiff floor for all that
>> Spanish tile, and they are very quiet except for hard objects or certain
>> shoes falling on the tile floors above.
>>
>> Incidentally, through his travels to the US, my padrino has been impressed
>> with commercial construction. However, he thinks some US houses are quite
>> beautiful but the construction quality is poor for such a rich country.
>> Especially here in Florida, where we are obviously in a hurricane-prone
>> region, he cannot understand (outside of economics) why we use so much
>> wood...
>>
>> Andrew Kester, PE
>>
>> ******* ****** ******* ******** ******* ******* ******* ***
>> * 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
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>> * Questions to seaint-ad@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 <http://www.seaint.org/>
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>>
>>
>
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> * Association of Southern California (SEAOSC) server. To
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>

Re: California SE exam

Regards,

Scott

Adrian, MI

On Oct 8, 2009, at 4:42 PM, "Lakhani, Sid" <slakhani@ebmud.com> wrote:

I am preparing for California SE exam (Seismic portion only). I passed the National portion in April which was based on IBC 06.

I have Seismic and Wind Forces Structural Design Examples 3^rd edition by Alan Williams,updated to IBC 2006.

Is there any similar guide/reference available with CBC 07 reference?

Thanks!

Sid

my periodic leak rant

Andrew
Based on my 7 years of doing nothing but residential forensic work in
the '90s in the San Francisco area I've concluded our construction
priorities are upside down. In Marin Co. all structural analysis &
design gets peer reviewed & final occupancy requires an Observation
report from the EOR for excavation, rebar, structural framing, & LFRS.
IMHO we could dispense with all of the above & replace it with compitent
inspection of the building's waterproof envelope. Heck, we could fire
all the structural engineers & come out way ahead if we just stopped the
leaks.
California is spending literally billions every year dealing with decay
& the design community and Building Departments don't see to be at all
concerned.
Chuck Utzman

akester@cfl.rr.com wrote:
> Richard has it right with newer homes in FL, although my house was built in the 50s and older homes often are crawspace on CMU stem walls and piers with wood frame walls. I like the look of heavy timber such as in ski lodges, and in log cabins, so it has its place. I am about to do a back porch addition out of exposed wood rafters with a 1x tongue and groove ceiling/decking. In dry, western, seismically active regions, I see why timber may be used as a preferable material. But I am a CMU guy all the way for Florida for all the reasons others have stated: wind pressure, wind borne debris debris, uplift resistance, termites, and moisture and vapor control, thermal R values, sound, and moisture and rot damage. In new construction in S FL you barely see wood at all except for trusses and interior walls. I did a forensic job at a house in Miami with a steel joist and concrete floor system, I was amazed...
>
> Since I have been doing a lot of forensics the last five years all over the state, a lot of the wood damage I have seen has made me a believer that it is an uphill battle in a sub tropical climate. Of course these things cannot be overlooked but usually are: sprinklers near buildings, the MUST of gutters and getting water away from buildings, proper and functional roof slope design (too many funky hips and valleys always creates problems), and flashing flashing flashing.... Just general smart architecture would help.
>
> Did a job a while back at a house with moisture damage and roof issues. They were from Bosnia and also not impressed with our construction methods.
>
> I think a lot of it has to do with the fast track nature of much of home construction during the bubble, especially in FL and probably in AZ, CA and other hot real estate market states. Big tract housing was thrown up at huge scales using untold numbers of subs who used unskilled immigrant workers (not their fault, just fact). The bottom line often wins out over quality. I got the same complaint from northerners/Yankees who pissed and moaned about how much better they did it up north. Maybe they have a point. But another dirty secret in the housing market, absent of a company like Richard's, is that many houses are not designed by professionals. I am not saying they are not signed and sealed by professionals, just not designed. It is the biggest off the shelf plan and copy and paste scam, and they can always find someone with a seal to rent. I know about if first hand, which is why I rarely did full residential jobs, and never did neighborhoods. Sorry, I will not just review and seal your drawings Residential Cad Design Inc. for $200.
>
> I digress, sorry this was long winded. Go CMU and concrete! Wood, sorry, you have your place. My dream house in FL will use wood on the floors, cabinets, balconies, and maybe some of the roof. Also, I am a big fan of a safe room. Every room in 'cane country should just take a master walk in closet or something like that and make it a safe room. CMU with #5s @ 40" o.c., all solid grout, 4" slab ceiling. No windows, hardened or steel door. 12" thick mat foundation. Bring it on! Then just design the rest of your house to code or a little higher. To me, that is the best mix of safety and practicality and economics...
>
> Andrew Kester, PE
>
>
>
>
> ******* ****** ******* ******** ******* ******* ******* ***
> * 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@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
> ******* ****** ****** ****** ******* ****** ****** ********
>
>