Structural Engineering: 2009-01-04

Saturday, January 10, 2009

RE: Is it just me?

Thanks, Oshin.

T. William (Bill) Allen, S.E.

Consulting Structural Engineers
V (949) 248-8588 • F(949) 209-2509

-----Original Message-----
From: Oshin Tosounian [mailto:oshin@sdgseinc.com]
Sent: Friday, January 09, 2009 8:40 PM
To: seaint@seaint.org
Subject: RE: Is it just me?

Bill,

Don’t bother. Check this first:

http://www.strongtie.com/literature/TechTopics/eccentric_holdowns.htm

Oshin Tosounian, S.E.

From: Bill Allen [mailto:t.w.allen@cox.net]
Sent: Friday, January 09, 2009 4:02 PM
To: Seaint
Subject: Is it just me?

When specifying a Simpson PHD hold down, one of the footnotes reads "Post design by Specifier." In looking at the HDQ8 in 2-2x4s, the capacity is listed as 5,715 lbs. Based on an eccentricity of 3"(CL=1.5" + 1.5" for one 2x), the weak axis bending moment due to the eccentricity is 1,428 ft.-lbs. Assuming the 2-2Xs are face nailed adequately to transfer VQ/I stresses, this moment results in a bending stress of 3,266 psi on the gross section. The allowable stress on a 2x4 DF-L section is of course quite a bit lower than this, not even considering combined stresses.

Have I forgotten how to properly draw a free body diagram or is there something else going on here?

Otherwise, is it misleading to list 2-2Xs with a hold down of this capacity?

Regarding the VQ/I stresses, if the height of the studs are 8 feet, then the shear on the post is Pe/h = (1428)/(8)= 179 lbs. Then VQ/I = (179)((3.938)/(7.875)=90 lbs/in. Using 10d FN (capacity = 115 x 1.60 = 184 lbs each), the spacing would be 184/90 = 2" o.c.

This doesn't seem right to me.

If the two studs aren't nailed adequately to transfer VQ/I stresses, then the bending stress due to the eccentricity is even higher (6,528 psi) since S reduces to 2x1.313= 2.625 in³ from 5.25 in³.

Maybe I should put away the calculator on Friday afternoons.

If anyone would care to shed some light on the calculations, I would be most appreciative.

Thanks,

T. William (Bill) Allen, S.E.

ALLEN DESIGNS

Consulting Structural Engineers
V (949) 248-8588 • F(949) 209-2509

Friday, January 9, 2009

RE: Is it just me?

Bill,

Don’t bother. Check this first:

http://www.strongtie.com/literature/TechTopics/eccentric_holdowns.htm

Oshin Tosounian, S.E.

From: Bill Allen [mailto:t.w.allen@cox.net]
Sent: Friday, January 09, 2009 4:02 PM
To: Seaint
Subject: Is it just me?

Have I forgotten how to properly draw a free body diagram or is there something else going on here?

Otherwise, is it misleading to list 2-2Xs with a hold down of this capacity?

This doesn't seem right to me.

If the two studs aren't nailed adequately to transfer VQ/I stresses, then the bending stress due to the eccentricity is even higher (6,528 psi) since S reduces to 2x1.313= 2.625 in³ from 5.25 in³.

Maybe I should put away the calculator on Friday afternoons.

If anyone would care to shed some light on the calculations, I would be most appreciative.

Thanks,

T. William (Bill) Allen, S.E.

ALLEN DESIGNS

Consulting Structural Engineers
V (949) 248-8588 • F(949) 209-2509

Re: Is it just me?

Bill:

I didn't do the math, but I would never use 2 studs, because I know from my past field experienc that it is not likely that the contractor will provide the proper nailing stud to stud anyway. I would use a 4x4 and sleep nights.

Ray Shreenan

----- Original Message -----

From: Bill Allen

To: Seaint

Sent: Friday, January 09, 2009 4:01 PM

Subject: Is it just me?

When specifying a Simpson PHD hold down, one of the footnotes reads "Post design by Specifier." In looking at the HDQ8 in 2-2x4s, the capacity is listed as 5,715 lbs. Based on an eccentricity of 3"(CL=1.5" + 1.5" for one 2x), the weak axis bending moment due to the eccentricity is 1,428 ft.-lbs. Assuming the 2-2Xs are face nailed adequately to transfer VQ/I stresses, this moment results in a bending stress of 3,266 psi on the gross section. The allowable stress on a 2x4 DF-L section is of course quite a bit lower than this, not even considering combined stresses.

Have I forgotten how to properly draw a free body diagram or is there something else going on here?

Otherwise, is it misleading to list 2-2Xs with a hold down of this capacity?

Regarding the VQ/I stresses, if the height of the studs are 8 feet, then the shear on the post is Pe/h = (1428)/(8)= 179 lbs. Then VQ/I = (179)((3.938)/(7.875)=90 lbs/in. Using 10d FN (capacity = 115 x 1.60 = 184 lbs each), the spacing would be 184/90 = 2" o.c.

This doesn't seem right to me.

If the two studs aren't nailed adequately to transfer VQ/I stresses, then the bending stress due to the eccentricity is even higher (6,528 psi) since S reduces to 2x1.313= 2.625 in³ from 5.25 in³.

Maybe I should put away the calculator on Friday afternoons.

If anyone would care to shed some light on the calculations, I would be most appreciative.

Thanks,

T. William (Bill) Allen, S.E.

ALLEN DESIGNS

Consulting Structural Engineers
V (949) 248-8588 • F(949) 209-2509

RE: Is it just me?

There was an article about this is "Structure" magazine or "Structural
Engineer" magazine about this 8 or 9 years ago. I wrote a spreadsheet for
it. It is hard to make laminated studs work even with composite action. My
spreadsheet assumed each stud just grabs an equal amount of the moment. I
think the reason Simpson says its on the specifier because by code it hardly
ever calcs out.

I wouldn't sleep tonight if I were you knowing all the walls the are going to
crack in half at the holdowns during the next big one.

-----Original Message-----
From: Bill Allen [mailto:t.w.allen@cox.net]
Sent: Friday, January 09, 2009 3:02 PM
To: Seaint
Subject: Is it just me?

When specifying a Simpson PHD hold down, one of the footnotes reads "Post
design by Specifier." In looking at the HDQ8 in 2-2x4s, the capacity is
listed as 5,715 lbs. Based on an eccentricity of 3"(CL=1.5" + 1.5" for one
2x), the weak axis bending moment due to the eccentricity is 1,428 ft.-lbs.
Assuming the 2-2Xs are face nailed adequately to transfer VQ/I stresses, this
moment results in a bending stress of 3,266 psi on the gross section. The
allowable stress on a 2x4 DF-L section is of course quite a bit lower than
this, not even considering combined stresses.

Have I forgotten how to properly draw a free body diagram or is there
something else going on here?

Otherwise, is it misleading to list 2-2Xs with a hold down of this capacity?

Regarding the VQ/I stresses, if the height of the studs are 8 feet, then the
shear on the post is Pe/h = (1428)/(8)= 179 lbs. Then VQ/I =
(179)((3.938)/(7.875)=90 lbs/in. Using 10d FN (capacity = 115 x 1.60 = 184
lbs each), the spacing would be 184/90 = 2" o.c.

This doesn't seem right to me.

If the two studs aren't nailed adequately to transfer VQ/I stresses, then the
bending stress due to the eccentricity is even higher (6,528 psi) since S
reduces to 2x1.313= 2.625 in3 from 5.25 in3.

Maybe I should put away the calculator on Friday afternoons.

If anyone would care to shed some light on the calculations, I would be most
appreciative.

Thanks,

T. William (Bill) Allen, S.E.

ALLEN DESIGNS <http://www.AllenDesigns.com>

Consulting Structural Engineers
V (949) 248-8588 * F(949) 209-2509

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RE: Is it just me?

Bill:

You're just checking for bending. The NDS requires a bending combined with
tension through the net section unity check. Now you just gave all the new
plan reviewers something to hassle designers about until the rapture in 2012.

Scott

-----Original Message-----
From: Bill Allen [mailto:t.w.allen@cox.net]
Sent: Friday, January 09, 2009 3:02 PM
To: Seaint
Subject: Is it just me?

When specifying a Simpson PHD hold down, one of the footnotes reads "Post
design by Specifier." In looking at the HDQ8 in 2-2x4s, the capacity is
listed as 5,715 lbs. Based on an eccentricity of 3"(CL=1.5" + 1.5" for one
2x), the weak axis bending moment due to the eccentricity is 1,428 ft.-lbs.
Assuming the 2-2Xs are face nailed adequately to transfer VQ/I stresses, this
moment results in a bending stress of 3,266 psi on the gross section. The
allowable stress on a 2x4 DF-L section is of course quite a bit lower than
this, not even considering combined stresses.

Have I forgotten how to properly draw a free body diagram or is there
something else going on here?

Otherwise, is it misleading to list 2-2Xs with a hold down of this capacity?

Regarding the VQ/I stresses, if the height of the studs are 8 feet, then the
shear on the post is Pe/h = (1428)/(8)= 179 lbs. Then VQ/I =
(179)((3.938)/(7.875)=90 lbs/in. Using 10d FN (capacity = 115 x 1.60 = 184
lbs each), the spacing would be 184/90 = 2" o.c.

This doesn't seem right to me.

If the two studs aren't nailed adequately to transfer VQ/I stresses, then the
bending stress due to the eccentricity is even higher (6,528 psi) since S
reduces to 2x1.313= 2.625 in3 from 5.25 in3.

Maybe I should put away the calculator on Friday afternoons.

If anyone would care to shed some light on the calculations, I would be most
appreciative.

Thanks,

T. William (Bill) Allen, S.E.

ALLEN DESIGNS <http://www.AllenDesigns.com>

Consulting Structural Engineers
V (949) 248-8588 * F(949) 209-2509

Is it just me?

Have I forgotten how to properly draw a free body diagram or is there something else going on here?

Otherwise, is it misleading to list 2-2Xs with a hold down of this capacity?

This doesn't seem right to me.

If the two studs aren't nailed adequately to transfer VQ/I stresses, then the bending stress due to the eccentricity is even higher (6,528 psi) since S reduces to 2x1.313= 2.625 in³ from 5.25 in³.

Maybe I should put away the calculator on Friday afternoons.

If anyone would care to shed some light on the calculations, I would be most appreciative.

Thanks,

T. William (Bill) Allen, S.E.

ALLEN DESIGNS

Consulting Structural Engineers
V (949) 248-8588 • F(949) 209-2509

RE: Paying for clarification

The project is a design-build remodel. There are a lot of details to be worked out. I submitted a bare minimum amount of details to get into the plan check cue. I fully expected there would be questions and I was ready to provide a few extra calcs/details upon resubmittal along with my plan for submitting future revisions. I got no corrections:\

Michel

From: Gil Brock [mailto:gil@raptsoftware.com]
Sent: Wednesday, January 07, 2009 2:46 PM
To: seaint@seaint.org
Subject: RE: Paying for clarification

Michel,

At 04:03 AM 8/01/2009, you wrote:

> I don’t want the plan checker signing off my work because I am a 60-ish year old white haired engineer who he believes has the great knowledge of experience to rely upon.

I am 30-ish and am having insecure feelings that the plan checkers are starting to rely a little to much on me. I am not being arrogant, but I expected corrections on several of my recent submittals and got almost none.

Maybe I am mis-interpreting your comment but I find it worrying that you are relying on plan checkers to find your mistakes. Maybe I am old fashioned having but I always thought it was my job as a designer to get it right in the first place and make sure it leaves the office ready to be built. Not to be simply a first rough attempt at a design which I hope someone else will fix for me!

Regards Gil Brock
Prestressed Concrete Design Consultants Pty. Ltd. (ABN 84 003 163 586)
5 Cameron Street Beenleigh Qld 4207 Australia
Ph +61 7 3807 8022               Fax +61 7 3807 8422
email:            gil@raptsoftware.com
email:            sales@raptsoftware.com
email:            support@raptsoftware.com
webpage:         http://www.raptsoftware.com

Code Discussion

Dennis,
I know you (and several others) do not have a favorable opinion of the
recent building codes and the code writers but I would like to point out
that some these engineers spend hundreds/thousands of volunteer hours on
our behalf (there are others that the code committee is part of the
regular job). If we are not happy with the current progress, why not
volunteer some hours to make it better? I would rather spend my time and
passion improving the industry/code.

Each code committee is made up of a certain percentage of consumers
(design engineers from large, medium, and small companies), academia,
producers (industry rep's like masonry society) and building code
officials. There is just never enough volunteer-hours to do everything
on the committee's wish list so things only get done when someone
champions that particular item. Depending on how much time we have to
spare, let's put our money/time where our mouths are. ;-) Below is a
brief list of possibilities and I am sure there are more.

1.Joining one of the code committees - instructions are on the websites
and some are listed below for those interested. Time would be at least a
few hundred hours per year plus travel so this is for the most
dedicated:
ASCE7- http://content.seinstitute.org/committees/codes.html
IBC codes- www.iccsafe.org/cs/codes
ACI- http://www.concrete.org/COMMITTEES/COM_JOIN.asp
State building code- most adopt IBC with their own amendments and have
their own stru committee to review/accept and make changes
NCSEA- http://ncsea.com/directory.aspx?GroupID=6

2.Coming up with code language (or a reasonable attempt) to help simply
or improve the code and send to the chair of the respective committee.
Time could be anywhere from a few hours to a few hundred. Another
similar option would be to submit during public review period for each
code but I think the earlier in the code cycle the better chance of
getting it accepted into the code.

3. Emailing the committee chair/member and volunteering to proof some
new design methodology (say a simplified procedure) and compare it to
the current code offering results and feedback. This would be a good way
to contribute for someone, who is more limited on their volunteer hours.

With regard to the time cycle, I know ASCE 7 recently went to a 5 year
code cycle, which I personally feel was a step in the right direction.

Dennis, I know that you have personally spent a huge number of hours
volunteering to time and passion with SEAINT/SEA. I personally
appreciate what you have given of yourself through SEAINT. So Toda raba!
("thank you very much" in your Hebrew tongue). Over the past decade I
have benefited from your wisdom and your willingness to share your
knowledge..and I am in no way saying any one
person/committee/organization is anywhere near perfect. I have felt your
frustration through your posts. If perhaps, say, this time next year,
you still feel the same way about the specific code
committee/organization's lack of appreciation of your efforts, maybe try
another one. I am sure there is one out there that is the perfect fit
and would be extremely grateful for your efforts. You are a talented
engineer and leader. ;-)

Respectfully, Donna (who is attempting to do her small part to make the
codes better as an assoc committee member.)

_____________________________________
Donna Friis, P.E.
Structural Engineer
CDM
2301 Maitland Center Parkway, Ste 300
Maitland, FL 32751
Tel: (407) 660-6415, Fax: (407) 660-1243
mailto:FRIISDL@CDM.COM
www.cdm.com
_____________________________________

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17 Message:0017
17
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From: "Dennis Wish" <dennis.wish@verizon.net>
To: <seaint@seaint.org>
Subject: If so many agree, why remain apathetic - Code Discussion

This is a multipart message in MIME format.

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charset="us-ascii"
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I had not checked my e-mail in a few days (at least the seaint.org
list). I
suppose that I have almost lost interest in my profession due to the
seeming
attacks against small practitioners in the form of "improve the code and
damn construction quality" ideology of the professional code committees.
I
certainly did not expect near 100% agreement with me on my last rant. So
this leads me to my next question;

If you believe that the code creation process is flawed or that that the
professional associates and supporting industries are maintaining a code
publication schedule that results only in a market for those who wish to
sell books or hold seminars to explain in the most trivial means a
complicated method, then why do you continue to support the profession
rather than take a proactive if not anarchistic approach to changing our
profession (now for a deep breath). Seriously, I stood on principle
after
the debacle in 2000 over the codification of the 97 UBC along with the
internal censorship of the SEAINT Online paper publication I wrote and
SEAOSC distributed in 9 states by simply resigning from SEA?
Organizations
such as this are, in my best days, very worthwhile when they represent
their
members and serve to improve the quality of construction rather than
finding
a new and convoluted means to solve the same problems we were doing in
one
line calculations for years.

Seriously, as practitioners we made mistakes. For years we designed
plywood
shear walls based on an aspect ratio of height to width rather than
addressing actual deflection and it seems that we have inordinately paid
the
price many times over while the code creative committees of our
profession
continually put out "drek" (junk for those of you not of the Jewish
faith)
creating a vacuum for prescriptive codes to take over as most of us lost
in
the rhetoric lose design work on residential and low-rise wood framed
structures. These structures represent almost 90% of all buildings
erected
in the United States and are the source of income for most sole
proprietorships or small offices. Yes, we diversify and write insurance
reports, act as expert witnesses, repair damaged and non-compliant
buildings, but while the housing industry is in a downward spiral why
are we
not becoming more active as an independent group to force the code
creation
process back on track?

Years ago I believed the chasm between Architects / NAHB and Engineers
was
so wide that the differences could not be resolved politically. There is
a
need for prescriptive design, but as we learn more about wind and
seismic,
it seems the prescriptive methods won't cut it - yet this is what is
allowed
in the IRC and what we must compete with in the layperson world of our
clients and hungry developers.

This list (which I lay claim to creating with Shafat Qazi and the
support of
SEAOSC) has close to 15,000 members worldwide and certainly the power in
dues paid to the associations to make a difference. If the money dries
up so
does the work of the committees. Let me make this perfectly clear. I am
not
in favor of bringing SEA or ASCE or any other group down, I am in favor
of
reminding them forcefully how things were done before the computer age
when
SEA in California was still small and growing and ethics allowed SEA to
place their members first. Now the members are nothing more than a
source of
revenue to pay for dues, seminars, publications etc. In 2000+ when we
argued
the 97 code, we discovered that this list was able to hit an end of the
road
block wall that it could not pass. The list is a bitching post where
members
can work off frustration. We do serve the needs of peer-to-peer help and
this is a value we should not discount, but my goal to the creation of
the
list was to allow for all members to be able to speak and be heard as a
serious voice. This is not happening and possibly won't. After the
SEAOSC
board hears of this message, I may be history - but at least it is off
my
chest.

If the code is imperfect we have an ethical obligation to change our
profession rather than leave it to the few Sheppard's leading the lambs
to
slaughter. If you are interested, write me privately and I will start an
online petition which can be our voice by those not on the list who
still
have a voice in SEA. Next year, Michael Cochran, SE takes over as
president
of SEAoSC and as a former member I look forward to this change. Not only
do
I highly respect Michael as a friend and professional peer, but the
current
board president leaves much to be desired by means of compromise or
working
with the members for meaningful change. I believe Michael is more
empathetic
to the needs of the members as was his father Brian Cochran when I was
just
a young new active member of various committees.

Don't give in - become an active voice in change and it may just spread
into
an international effort.

Sincerely,

Dennis S. Wish

Dennis S. Wish, PE

California Professional Engineer (C-41250)

Structural Engineering

54625 Avenida Bermudas

La Quinta, CA. 92253

Phone: 760.564.0884 (phone, fax and messages)

dennis.wish@verizon.net

Thursday, January 8, 2009

RE: Paying for clarification

Dennis,

Try Standards Australia

http://www.standards.org.au/

type in code number and it will take to SAI global, from which can get
standards from around the world.

Here is AS4055 link

http://www.saiglobal.com/shop/script/Result.asp?DegnKeyword=AS4055&Db=AS&Sea
rchType=publisheronly&Status=all&Max=15&Search=Proceed

If ANSI is like AS then can probably get them from there.

Sorry AS only give brief description of code. No pdf to review. Though if
search site may find draft copy for public review.

Best I can do is scan a few pages. But don't have scanner set up at moment,
so may take a few days/weeks.

I have a simple Excel workbook for AS4055: which compares against AS1170.2.
I have placed some of my AS1170.2 and AS40555 workbooks on ExelCalcs:

http://www.excelcalcs.com

Or I can email directly.

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

RE: Paying for clarification

Dennis - try this:

http://www.gostructural.com/article.asp?id=2636

T. William (Bill) Allen, S.E.
ALLEN DESIGNS
Consulting Structural Engineers
V (949) 248-8588 . F(949) 209-2509

-----Original Message-----
From: Dennis Wish [mailto:dennis.wish@verizon.net]
Sent: Thursday, January 08, 2009 9:19 PM
To: seaint@seaint.org
Subject: RE: Paying for clarification

Are these available online on a reference site for review? Where do I find
them in the US?

Regards,

Dennis

-----Original Message-----
From: Conrad Harrison [mailto:sch.tectonic@bigpond.com]
Sent: Thursday, January 08, 2009 8:17 PM
To: seaint@seaint.org
Subject: RE: Paying for clarification

Dennis and others,

For an example of simplified wind loading take a look at:

AS4055: Wind loads for housing
AS1684.1 : Residential timber-framed construction : Design Criteria
AS1684.2 : Residential timber-framed construction : Non-cyclonic areas
AS1684.3 : Residential timber-framed construction : cyclonic areas

These are derived from and dependent on:

AS1170.2 : Structural Design Actions Part 2: Wind Actions
AS1720 : Timber Structures Code

AS1170.2 is similar to ASCE7-05, in the office I can trace it back to 1973,
which seems to be the first metric edition, prior to that seems to have been
called CA34. I assume ASCE7 has similar vintage and it didn't just spring
out off nowhere in 2005. Personally I'd expect licensed SE's to use ASCE7
and have significant experience using it, and be capable of simplifying for
themselves.

I don't have the wood framed construction manual (WFCM), but I have been
assuming it is similar to AS1684.1 and presents a prescriptive application
of ASCE7, identifying the pressure coefficients to use for rafters, studs
etc. If it has pressures like IBC:2003 (ps30), then it is too limited in
application. Though IR 16-7 seems to be heading in right direction.

Also given that the WFCM guides refer to V and exposure B, as does IBC:2003,
does suggest an industry wide lack of understanding of ASCE7 and the
calculation of qz and the relative constancy of pressure coefficients for a
given structural application. Whilst qz is a trivial calculation to suit the
site/building combination.

Using AS1684.2 a timber estimator, builder or architect can look up
pressures to apply to projected areas or directly look up forces for
tie-down and bracing. Once they have the applied force they can also look up
resistances and select appropriate connection and bracing details.
(Comparing against IBC:2003, I'd say connections given in IBC are not
suitable for V=100mph)

AS1684 = Simplified: no engineer required.

Though the tables in AS168.2 only go up to wind class N4. However wind class
N3 to N6 have same reference design speed (Vzu, qzu) as cyclonic classes C1
to C4. So for wind classes N5 to N6 could use the cyclonic prescriptions.

Being simplified AS4055 also tends to be conservative, and often builders
get engineers to check to AS1170.2 to reduce wind load and thus tie-down and
bracing requirements. Builders however, take member sizes from the span
tables, because, it would take far longer than 30 minutes to engineer all
the timber in a typical house. (AS1684 is only valid for 2 storeys)

And as an engineering technologist, with formal education in industrial,
manufacturing, and mechanical engineering, and having to learn structural
codes on the job: I most certainly expect a registered structural engineer
(NPER) to know more about AS1170.2 than I do. All my calc's are checked and
certified by engineers: though development act currently calls up
NPER(Civil): but structural relatively recent addition to NPER.

Whilst ASCE7-05 is not my code, I don't really see any difficulty learning
the wind loading requirements. The only difficulty I am having is
understanding the potential misapplication of empirical research and the
inappropriate prescriptive measures in the use of C&C pressures.

For if the way everyone wants to apply ASCE7-05 C&C pressures is correct,
then for years wind loads have been too low, and the MWFRS pressures are a
waste of time. Why calculate a gust factor G which comes out less than 0.85,
if all components (rafters, wall studs, trusses) have to be designed loaded
along entire span with C&C pressures?

The MWFRS Cp=+0.8 (Fig6-6) for windward wall does not occur over all the
surface of the wall at the same time, it is a peak value. Also say Cp=-0.4
on windward edge during transverse loading does not occur over entire
surface of a single roof plane. Further more these extremes do not occur at
the same time on all the surfaces being considered. The pressures based on
therefore should not be unconservative for design of a truss, or rafter or
wall stud.

There is a significant difference between applying external Cpe(W,L) for
roof planes of Cp(-0.4, -0.6), then deciding to be conservative and adopting
Cp(-0.6,-0.6) and then going ultra-conservative and replacing with magnified
C&C pressures Cp(-1.2,-1.2), assuming magnification factor from MWFRS to C&C
is 2. Which is effectively the consequence of applying C&C pressures to
design of a truss. Obviously the truss manufacturers will oppose: when
Cp(-0.4,-0.6) has otherwise been adequate for years: and implication is did
survive cyclone Larry if internal pressure set to Cpi=+0.7 (windows broken),
and topographical features considered: buildings not so designed were
amongst the wreckage.

However, difficult to have sensible discussion about wind loading
requirements when far too many are declaring ASCE7-05 far too complex.
Rather than referring to texts on the subject, and suggesting conservative
and practical simplifications which comply with ASCE7.

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

RE: Paying for clarification

Are these available online on a reference site for review? Where do I find
them in the US?

Regards,

Dennis

-----Original Message-----
From: Conrad Harrison [mailto:sch.tectonic@bigpond.com]
Sent: Thursday, January 08, 2009 8:17 PM
To: seaint@seaint.org
Subject: RE: Paying for clarification

Dennis and others,

For an example of simplified wind loading take a look at:

These are derived from and dependent on:

AS1170.2 : Structural Design Actions Part 2: Wind Actions
AS1720 : Timber Structures Code

AS1684 = Simplified: no engineer required.

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

RE: Paying for clarification

Dennis and others,

For an example of simplified wind loading take a look at:

These are derived from and dependent on:

AS1170.2 : Structural Design Actions Part 2: Wind Actions
AS1720 : Timber Structures Code

AS1684 = Simplified: no engineer required.

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

If so many agree, why remain apathetic - Code Discussion

I had not checked my e-mail in a few days (at least the seaint.org list). I suppose that I have almost lost interest in my profession due to the seeming attacks against small practitioners in the form of “improve the code and damn construction quality” ideology of the professional code committees. I certainly did not expect near 100% agreement with me on my last rant. So this leads me to my next question;

If you believe that the code creation process is flawed or that that the professional associates and supporting industries are maintaining a code publication schedule that results only in a market for those who wish to sell books or hold seminars to explain in the most trivial means a complicated method, then why do you continue to support the profession rather than take a proactive if not anarchistic approach to changing our profession (now for a deep breath). Seriously, I stood on principle after the debacle in 2000 over the codification of the 97 UBC along with the internal censorship of the SEAINT Online paper publication I wrote and SEAOSC distributed in 9 states by simply resigning from SEA? Organizations such as this are, in my best days, very worthwhile when they represent their members and serve to improve the quality of construction rather than finding a new and convoluted means to solve the same problems we were doing in one line calculations for years.

Seriously, as practitioners we made mistakes. For years we designed plywood shear walls based on an aspect ratio of height to width rather than addressing actual deflection and it seems that we have inordinately paid the price many times over while the code creative committees of our profession continually put out “drek” (junk for those of you not of the Jewish faith) creating a vacuum for prescriptive codes to take over as most of us lost in the rhetoric lose design work on residential and low-rise wood framed structures. These structures represent almost 90% of all buildings erected in the United States and are the source of income for most sole proprietorships or small offices. Yes, we diversify and write insurance reports, act as expert witnesses, repair damaged and non-compliant buildings, but while the housing industry is in a downward spiral why are we not becoming more active as an independent group to force the code creation process back on track?

Years ago I believed the chasm between Architects / NAHB and Engineers was so wide that the differences could not be resolved politically. There is a need for prescriptive design, but as we learn more about wind and seismic, it seems the prescriptive methods won’t cut it – yet this is what is allowed in the IRC and what we must compete with in the layperson world of our clients and hungry developers.

This list (which I lay claim to creating with Shafat Qazi and the support of SEAOSC) has close to 15,000 members worldwide and certainly the power in dues paid to the associations to make a difference. If the money dries up so does the work of the committees. Let me make this perfectly clear. I am not in favor of bringing SEA or ASCE or any other group down, I am in favor of reminding them forcefully how things were done before the computer age when SEA in California was still small and growing and ethics allowed SEA to place their members first. Now the members are nothing more than a source of revenue to pay for dues, seminars, publications etc. In 2000+ when we argued the 97 code, we discovered that this list was able to hit an end of the road block wall that it could not pass. The list is a bitching post where members can work off frustration. We do serve the needs of peer-to-peer help and this is a value we should not discount, but my goal to the creation of the list was to allow for all members to be able to speak and be heard as a serious voice. This is not happening and possibly won’t. After the SEAOSC board hears of this message, I may be history – but at least it is off my chest.

If the code is imperfect we have an ethical obligation to change our profession rather than leave it to the few Sheppard’s leading the lambs to slaughter. If you are interested, write me privately and I will start an online petition which can be our voice by those not on the list who still have a voice in SEA. Next year, Michael Cochran, SE takes over as president of SEAoSC and as a former member I look forward to this change. Not only do I highly respect Michael as a friend and professional peer, but the current board president leaves much to be desired by means of compromise or working with the members for meaningful change. I believe Michael is more empathetic to the needs of the members as was his father Brian Cochran when I was just a young new active member of various committees.

Don’t give in – become an active voice in change and it may just spread into an international effort.

Sincerely,

Dennis S. Wish

Dennis S. Wish, PE

California Professional Engineer (C-41250)

Structural Engineering

54625 Avenida Bermudas

La Quinta, CA. 92253

Phone: 760.564.0884 (phone, fax and messages)

dennis.wish@verizon.net

RE: Paying for clarification

Dennis,

That is not what I said. I along with everyone else makes mistakes. And there are many grey areas in design. My comment related to the statement "plan checkers are starting to rely a little to much on me".

Sounds to me like some engineers are relying too much on plan checkers to do their checking for them. In the same way that many architects these days (here I go getting into trouble again) are now relying on engineers to sort out their basic details for them.

At 10:55 AM 9/01/2009, you wrote:

Gil and Gautam,

I am a sole-proprietorship and have been in business as a small office/home office (SOHO) for over 22-years as I stated in the original e-mail. Anyone in my position is prone to making a mistake. I am not expecting the plan checker to educate me, but I sure as hell am expecting him to prevent something I overlooked or misinterpreted from getting past him. Without in-house peer review the plan checker is our last line of defense. To assume that we are perfect and should have a perfect package submitted for permit application also implies that there would be no purpose to plan check.

So, Gil, to assume that each of your packages leaves your office with all of the information completely accurate makes you very unique, possibly a deity. In our society of sole proprietors who juggle running a business, marketing, taking care of phone calls, billing, plan corrections (oops missed that one), and ringing phones and dead lines that are often rushed, the idea of perfection is a goal but not a reality. We strive for perfection, but achieving it 100% of the time is generally not possible.

Realistically, your argument goes to an extreme when my complaint is based on a centrist idea. In addition, if you consider perfection a realistic goal of the engineers package, how can you defend (if this is what you are doing) an imperfect code.

One short example; The 1997 UBC required by law (code) that almost all residential structures be designed as rigid diaphragm. The profession recommended, but did not change the code and therefore made each engineer responsible for potential liability through non-compliance with the letter of the law. I spent some time working as a sub-contractor to a contract plan check agency. Almost 100% of the submittals for structures in wood framing less than 3-stories were submitted using flexible diaphragm analysis with no consideration for rigid or semi-rigid diaphragm. In your comparison, you would have submitted the package in rigid because it is the letter of the law and therefore perfection while the profession's recommendation, that most used, cannot hold up in court if a failure should occur and the argument is that the diaphragm was rigid but the engineer followed a recommendation of the professional community that was not codified.

There is no such thing as perfection – it is only a goal we work to achieve.

Regards,

Dennis

From: Gautam Manandhar [ mailto:Gautam_Manandhar@ci.richmond.ca.us]
Sent: Thursday, January 08, 2009 3:48 PM
To: seaint@seaint.org
Subject: RE: Paying for clarification

Gil:

I agree with you that the designer should get it right in the first place. Mt attitude is that I am human and can (and will) make mistakes. To me, a good plan checker is a second set of eyes. I would rather he catch my mistakes rather that the contractor.

Gautam

From: Gil Brock [ mailto:gil@raptsoftware.com]
Sent: Wednesday, January 07, 2009 2:46 PM
To: seaint@seaint.org
Subject: RE: Paying for clarification

Michel,

At 04:03 AM 8/01/2009, you wrote:
> I don't want the plan checker signing off my work because I am a 60-ish year old white haired engineer who he believes has the great knowledge of experience to rely upon.

I am 30-ish and am having insecure feelings that the plan checkers are starting to rely a little to much on me. I am not being arrogant, but I expected corrections on several of my recent submittals and got almost none.

Maybe I am mis-interpreting your comment but I find it worrying that you are relying on plan checkers to find your mistakes. Maybe I am old fashioned having but I always thought it was my job as a designer to get it right in the first place and make sure it leaves the office ready to be built. Not to be simply a first rough attempt at a design which I hope someone else will fix for me!

Regards Gil Brock
Prestressed Concrete Design Consultants Pty. Ltd. (ABN 84 003 163 586)
5 Cameron Street Beenleigh Qld 4207 Australia
Ph +61 7 3807 8022               Fax +61 7 3807 8422
email:            gil@raptsoftware.com
email:            sales@raptsoftware.com
email:            support@raptsoftware.com
webpage:         http://www.raptsoftware.com

Regards Gil Brock
Prestressed Concrete Design Consultants Pty. Ltd. (ABN 84 003 163 586)
5 Cameron Street Beenleigh Qld 4207 Australia
Ph +61 7 3807 8022               Fax +61 7 3807 8422
email:            gil@raptsoftware.com
email:            sales@raptsoftware.com
email:            support@raptsoftware.com
webpage:         http://www.raptsoftware.com

Why continue to support professional associations involved in code creation?

If the majority of those who answered this are in agreement, then why the hell are you financially supporting the profession in dues to each association that is part of the code creation process. Why is there not more proactive movement among engineers to either slow down the code cycle in order to correct their errors and create less ambiguous rhetoric or simply leave your affiliation . At the codification and arguments that occurred upon the 1997 UBC, I understood that my only response to being stonewalled was to pull my financial support of SEA, ASCE or any other group who believes that they do not represent the foundation of members upon whose shoulders they stand?

Regards,

Dennis

From: Garner, Robert [mailto:rgarner@moffattnichol.com]
Sent: Tuesday, January 06, 2009 1:15 PM
To: seaint@seaint.org
Subject: RE: Paying for clarification

Dennis,

I am in total agreement with you. It's not appropriate to mention it here, but I have some ongoing i$$ues with S.K. Ghosh, also.

And as far as the new "codes" go, I agree with you, too.

I'm up to support a new code process. Anyone else?

Robert Garner, S.E.

From: Dennis Wish [mailto:dennis.wish@verizon.net]
Sent: Tuesday, January 06, 2009 12:32 PM
To: Seaint@seaint.org
Subject: Paying for clarification

I received an e-mail invitation to a one-day Seminar to be held on 1/15 and again on 2/18 featuring S.K. Ghosh, Susan Dowty and Kenneth Luttrell. For a fee plus airfare and accommodations (if necessary) I can fly from Palm Springs to Sacramento or Oakland to obtain clarification on the 2009 IBC new “Simplified Wind Design Provisions” (based on the ASCE 7-05/2006 IBC), Redundancy factor for Seismic Categories D through F, Rigid or Flexible Diaphragm flow chart to help identify when to you each procedure, and other important topics that have plagued us in 2008 since California adopted the ASCE 7-05/2006 IBC into the 2007 California Building Code. Before I comment, let me say that I am not criticizing Dr. Ghosh, Ms. Dowty or Mr. Luttrell for promoting a profit based or even if the earnings were donated to the profession a series of costly seminars.

My complaint is that I purchased the proper code manuals and accessory materials expecting to find the interpretations in a clear and concise format, flow-chart or explanation as I would expect to receive from the above seminar. I believe that the code publications committees had a responsibility to the engineering community to define the design process with as little ambiguity and with as much clarity as possible. For the engineers that I have spoken to in California, more than 80% of them have some level of confusion with how to interpret the code and coordinate the ASCE and IBC publications. I recent having to pay an additional amount of money that I can no longer afford to be sold another course or seminar only pay for something I believed I paid for already.

This reminds me of the Marx Brother’s “Day at the Races” when Groucho goes to the race track to place a two dollar bet. He is approached by Chico who tells Groucho that he can bet on a winner if only he buys the breeder’s guide. Groucho dishes out the money only to find the guide is in code. Chico tells him the code will cost extra and Groucho dishes out again to buy the code. Now the code identifies the jockey and and track information but does again Groucho will need to pay for yet two more books to identify the jockey and track information. Having no money left, Groucho cannot place his has bet, yet Chico places his with Groucho’s money and wins.

So who is the winner in this code creation debacles? Why publish and enforce a code that few can understand or properly comply with? Each trip to the building department reminds me of the mid 80’s when we wrote the draft for RGA 1-91 for seismic Retrofit in the City of L.A. to replace or augment Division 88. At the time, each submittal required special approval and plan checks were almost always a mutual learning experience devoted to debate.

I don’t want the plan checker signing off my work because I am a 60-ish year old white haired engineer who he believes has the great knowledge of experience to rely upon. I want to understand what I am doing and be sure that what I put on paper is properly thought out and not a risk to the public. Younger engineers have a tougher time than I might and I don’t believe I am any smarter or have any inside information than they do – in fact I would as much learn from an engineer much younger than I who has the understanding of what should have been presented to the practitioner in a clear and concise manner with examples at no additional price.

Am I the only one to think this way? Again, I am not criticizing education for those who have problems understanding the code after receiving a clear and non-ambiguous document that I expected to have originally paid for, but I doubt that even the seminar listed above could resolve all of this engineers questions in the one day seminar.

Sincerely,

Dennis S. Wish

Dennis S. Wish, PE

California Professional Engineer (C-41250)

Structural Engineering

54625 Avenida Bermudas

La Quinta, CA. 92253

Phone: 760.564.0884 (phone, fax and messages)

dennis.wish@verizon.net

RE: Wind design on hillside and slopes - tools

Yeah, but the Garmin GPS system is so much more fun when looking for
addresses and book stores :)

Happy New Year, Scott. How's the pup!

Regards,

Dennis

-----Original Message-----
From: Scott Maxwell [mailto:smaxwell@umich.edu]
Sent: Tuesday, January 06, 2009 6:37 PM
To: seaint@seaint.org
Subject: RE: Wind design on hillside and slopes - tools

You can get a good set of electronic topo maps from DeLorme. It only costs
$100 for the whole US. That is what I have used when have done the topo
factor on some projects. It will let you located site (most of time) by
street address...or you can always use lat and long.

Regards,

Scott
Adrian, MI

...... Original Message .......
On Tue, 6 Jan 2009 16:04:19 -0800 "Jeff Smith" <jeffsmith7@comcast.net>
wrote:
>
>I use a trail GPS for recreation , I wish I had remembered to take it with
me to the site I mentioned in my wind topo post. Since I do not have good
topo info, I started looking at google earth. You can get elevations by
moving your mouse over the image and you can measure distances with the
ruler tool. Unfortunatley there is not an topo layer in Google Earth, but
there is a topo terrain view in Google Maps, so you can go back and forth
between the two. I found that you can download and open a USGS topo map
overlay .kmz file and it will place the map over your point of interest in
Google Earth and you can print out the map at decent resolution. I found it
to be kind of buggy and sometimes does not load or loads after a long
delay. I found the file on a blog and I am not sure if it is legal to
distribute so I have not posted the link.
>
>Jeff
>---------------
>From: Dennis Wish [mailto:dennis.wish@verizon.net]
>Sent: Tuesday, January 06, 2009 12:47 PM
>To: seaint@seaint.org
>Subject: Wind design on hillside and slopes - tools
>
>
>I received a Garmin Nuvis 205W GPS for my car from family. The prices are
dropping and it was purchased for $100.00 locally and is normally over
$200.00. I discovered that it is not only accurate for pedestrian use to
find a cache from a game posted on the Garmin website where coordinates are
provided to help you locate a point of interest cache, but that the device
also maintained a proper elevation measurement while driving up into the
mountains. In the current wind force analysis of ASCE 7-05, a hillside
structure needs to be analyzed for wind traveling up the slope. The bottom
and top elevation of the hill needs to be