Structural Engineering: 2008-11-23

Thursday, November 27, 2008

Re: Use old 2D autocad typical details when putting plans together in Revit?

You load the 2D typical details in Revit and edit accordingly,,,

--- On Tue, 11/25/08, Ashwin Ranga Swamy <aswinpe@hotmail.com> wrote:

From: Ashwin Ranga Swamy <aswinpe@hotmail.com>
Subject: Re: Use old 2D autocad typical details when putting plans together in Revit?
To: seaint@seaint.org
Date: Tuesday, November 25, 2008, 10:03 AM

As a starting point I would suggest a hybrid set - major structural elements in
REVIT and details in AutoCAD.  Assuming it is a steel framed building, get all
your major steel framing in the model based on the Architectural background.  It
gets too cumbersome when you try to show every nut and bolt into the Revit
model.  You could show the sizes of the footings but rebar  and details could be
in  your AutoCAD drawing.  In this manner, you can still use the 2D standard
details.

Structural engineers have adapted the best to BIM since they have been working
with 3D analysis packages like ETABS and RISA for a very long time.


Hope this helps.

Ashwin Ranga Swamy, P.E.
Los Angeles, California

--------------------------------------------------
From: "Haan, Scott M POA" <Scott.M.Haan@usace.army.mil>
Sent: Monday, November 24, 2008 5:26 PM
To: <seaint@seaint.org>
Subject: Use old 2D autocad typical details when putting plans together in
Revit?

> I've never used a BIM model for putting together plans.  I am getting
thrown
> into a project using Revit where the 65% plans are due to soon, without
> training of course.
> 
> I haven't talked with anyone directly about their detail sheets when
they use
> BIM models for  their plans.  It seems like you don't want to draw all
your
> connections, slab on grade details etc... in 3D model space and put your
text
> for them in paper space.  It kind of defeats the purpose of typical
details.
> 
> Do people use their old  2D Autocad typical connection details and just
use
> the BIM model for the framing and foundation plans?
> 
> Thanks.
> 
> 
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Wednesday, November 26, 2008

Concrete Beam with Axial Loading

Does anyone have an example of the design of a rectangular concrete beam subjected to axial loads (tension/compression)? Of course, besides its common flexural and shear loads.

JJ

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Tuesday, November 25, 2008

RE: Progressive collapse

Maybe you should be thinking on PERFORM3D and SAP2000.

Sincerely,

-----Mensaje original-----
De: cairo briceño [mailto:cobdel@hotmail.com]
Enviado el: Martes, 25 de Noviembre de 2008 01:02 p.m.
Para: seaint@seaint.org
Asunto: Progressive collapse

Thank for your feedback on the software currently use for progressive collapse. We will looking into using SAP2000 or LSDYNA for the project.

Best regards.

Access your email online and on the go with Windows Live Hotmail. Sign up today.

Re: Use old 2D autocad typical details when putting plans together in Revit?

As a starting point I would suggest a hybrid set - major structural elements
in REVIT and details in AutoCAD. Assuming it is a steel framed building,
get all your major steel framing in the model based on the Architectural
background. It gets too cumbersome when you try to show every nut and bolt
into the Revit model. You could show the sizes of the footings but rebar
and details could be in your AutoCAD drawing. In this manner, you can
still use the 2D standard details.

Structural engineers have adapted the best to BIM since they have been
working with 3D analysis packages like ETABS and RISA for a very long time.

Hope this helps.

Ashwin Ranga Swamy, P.E.
Los Angeles, California

--------------------------------------------------
From: "Haan, Scott M POA" <Scott.M.Haan@usace.army.mil>
Sent: Monday, November 24, 2008 5:26 PM
To: <seaint@seaint.org>
Subject: Use old 2D autocad typical details when putting plans together in
Revit?

> I've never used a BIM model for putting together plans. I am getting
> thrown
> into a project using Revit where the 65% plans are due to soon, without
> training of course.
>
> I haven't talked with anyone directly about their detail sheets when they
> use
> BIM models for their plans. It seems like you don't want to draw all your
> connections, slab on grade details etc... in 3D model space and put your
> text
> for them in paper space. It kind of defeats the purpose of typical
> details.
>
> Do people use their old 2D Autocad typical connection details and just
> use
> the BIM model for the framing and foundation plans?
>
> Thanks.
>
>
> ******* ****** ******* ******** ******* ******* ******* ***
> * 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
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>

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RE: seismic forces

Chris,

Depending on your POV, Williams may even be better. As a talented but not bestselling SF/Fantasy author, Williams, unlike Mr. King, still gets edited...

(And I have read THE RIFT. Very well written.)

Gary

Gary J. Ehrlich, PE
Program Manager, Structural Codes & Standards
National Association of Home Builders (NAHB)
1201 15th Street, NW, Washington, DC 20005
ph: 202-266-8545 or 800-368-5242 x8545
fax: 202-266-8369
gehrlich@nahb.com
Attend the 2009 International Builders' Show
January 20-23, 2009, Las Vegas, NV
www.BuildersShow.com

-----Original Message-----
From: Christopher Wright [mailto:chrisw@skypoint.com]
Sent: Tuesday, November 25, 2008 12:08 PM
To: seaint@seaint.org
Subject: Re: seismic forces

On Nov 25, 2008, at 8:47 AM, Mike Jones wrote:

> Walter Jon Williams wrote a fictional account of a NM event
> happening "Today".
Probably something like 'Lucifer's Hammer.' I used to read a lot of
apocalyptic science fiction--if Williams is as good as _The Stand_
(Stephen King) it'll be pretty damn good.

In a related vein, the statistical approach to earthquake occurrence
give me serious heartburn. Nuke plants all have reams of SSE and OBE
response spectra, including plants in Minnesota and Nebraska and
other states with no particular seismic history. I play by the rules
and use them as if they were revealed wisdom, but sometimes I wonder
what the reality actually is. The whole process is so non-linear, I
can't imagine that any two damaging earthquakes really have any
similarity. The plates seem to move in the same relative direction,
but the contact geometry must really change enormously over time and
certainly during an earthquake. Tack on the discovery of new fault
lines from time to time and the predictability must be very iffy.

The small quakes probably do repeat to a degree, but extrapolation of
small quake behavior, which necessarily doesn't change much, to large
quake response which can move river beds seems like a leap of faith,
not science.

It really seems like a big stretch to pronounce a certain
acceleration as having a '2%-in-50 chance of exceeding an M7.1 to
M7.3 earthquake.' Statistical analysis of this sort demands a fairly
large population of nominally similar members and a solid
quantitative data base for numerical comparison. Damaging earthquakes
just don't fit these requirements, especially the big ones like the
Charleston and New Madrid quakes. We really can't determine when a
future earthquake may occur, let alone how big it might be, simply
because we only have so few examples. The idea of imposing some
notion of a time element on the really damaging quakes, to quantify
repetition seems far-fetched. The validity of a 2500 year event is
nonsensical. Seems to me like the do-something-even-if-it's-wrong
philosophy that we've all had to sweep up after.

Christopher Wright P.E. |"They couldn't hit an elephant at
chrisw@skypoint.com | this distance" (last words of Gen.
.......................................| John Sedgwick, Spotsylvania
1864)
http://www.skypoint.com/members/chrisw/

Re: seismic forces

Chris,

This goes to the bottom of my original post.

Thank you,

V. Steve Gordin, SE
Irvine CA

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

From: Christopher Wright

To: seaint@seaint.org

Sent: Tuesday, November 25, 2008 09:08

Subject: Re: seismic forces

On Nov 25, 2008, at 8:47 AM, Mike Jones wrote:

> Walter Jon Williams wrote a fictional account of a NM event
> happening "Today".
Probably something like 'Lucifer's Hammer.' I used to read a lot of
apocalyptic science fiction--if Williams is as good as _The Stand_
(Stephen King) it'll be pretty damn good.

In a related vein, the statistical approach to earthquake occurrence
give me serious heartburn. Nuke plants all have reams of SSE and OBE
response spectra, including plants in Minnesota and Nebraska and
other states with no particular seismic history. I play by the rules
and use them as if they were revealed wisdom, but sometimes I wonder
what the reality actually is. The whole process is so non-linear, I
can't imagine that any two damaging earthquakes really have any
similarity. The plates seem to move in the same relative direction,
but the contact geometry must really change enormously over time and
certainly during an earthquake. Tack on the discovery of new fault
lines from time to time and the predictability must be very iffy.

The small quakes probably do repeat to a degree, but extrapolation of
small quake behavior, which necessarily doesn't change much, to large
quake response which can move river beds seems like a leap of faith,
not science.

It really seems like a big stretch to pronounce a certain
acceleration as having a '2%-in-50 chance of exceeding an M7.1 to
M7.3 earthquake.' Statistical analysis of this sort demands a fairly
large population of nominally similar members and a solid
quantitative data base for numerical comparison. Damaging earthquakes
just don't fit these requirements, especially the big ones like the
Charleston and New Madrid quakes. We really can't determine when a
future earthquake may occur, let alone how big it might be, simply
because we only have so few examples. The idea of imposing some
notion of a time element on the really damaging quakes, to quantify
repetition seems far-fetched. The validity of a 2500 year event is
nonsensical. Seems to me like the do-something-even-if-it's-wrong
philosophy that we've all had to sweep up after.

Christopher Wright P.E. |"They couldn't hit an elephant at
chrisw@skypoint.com   | this distance" (last words of Gen.
.......................................| John Sedgwick, Spotsylvania
1864)
http://www.skypoint.com/members/chrisw/

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Re: seismic forces

On Nov 25, 2008, at 8:47 AM, Mike Jones wrote:

RE: seismic forces

An interesting comparison was recorded in Gottingen, Germany and compares the 1906 San Francisco earthquake with the 1989 Loma Prieta event. One can only imagine the 1812 or 1886 events.

http://earthquake.usgs.gov/regional/nca/1906/18april/got_seismogram_lp.php

Regards, Harold Sprague

Subject: RE: seismic forces
Date: Tue, 25 Nov 2008 09:05:33 -0500
From: gehrlich@nahb.com
To: seaint@seaint.org

The other factor that plays into the New Madrid and Charleston-area ground motions is that neither event (1812 or 1886) was recorded by seismographs. So, the "official" magnitudes are largely estimates based on the observed damage patterns (with a little bit of geology thrown in). And the average of the several estimates was weighted towards the higher guesses. So the seismic hazard in both places is essentially based on a 2%-in-50 chance of exceeding an M7.1 to M7.3 earthquake, which makes the MCE for those two areas a pretty damn big earthquake—ignoring the possibility that the 1812 and 1886 events ARE the 2500-year events. And, because the CEUS ground motions are not deterministically capped, the ground motions therefore come out equal to or larger than those along the well-known California faults.

Regards,

Gary

Gary J. Ehrlich, PE
Program Manager, Structural Codes & Standards
National Association of Home Builders (NAHB)
1201 15th Street, NW, Washington, DC 20005
ph: 202-266-8545 or 800-368-5242 x8545
fax: 202-266-8369
gehrlich@nahb.com
Attend the 2009 International Builders' Show
January 20-23, 2009, Las Vegas, NV
www.BuildersShow.com

From: Harold Sprague [mailto:spraguehope@hotmail.com]
Sent: Monday, November 24, 2008 8:25 PM
To: seaint@seaint.org
Subject: RE: seismic forces

It all happened on a dark and rainy night.

The BSSC NEHRP Provisions and NEHRP Commentary tell the story much better than I can. In a nut shell, the infrequent large historic earthquakes did not show up to properly characterize a uniform risk. The probability was adjusted to capture the large infrequent events by going to 2% excedance in 50 years as opposed to the more familiar 10% chance of excedance in 50 years and yielding a uniform hazard. This all happened in the late 1990's and was vetted with some incredibly bright engineers and seismologists. FEMA knew there was a problem, and the USGS zeroed in on it.

This probability shift made little difference in the classic California models, but made a huge difference in the Eastern North American seismic events. With all of that, there have been some recent revelations that indicate that the ENA events may be much more regular in time as evidenced in trenching studies. The implications are that a time dependent model may be more appropriate for ENA events. For example the NMSZ big one is actually 3 events occurring in less than a year but the triplets occur about every 400 years. This could drive the magnitude down in ENA events. But historically, these events were enormous and effected huge areas of the US because of the attenuation differences between ENA and Pacific rim earthquakes. In the NMSZ, between December 1811 and May 1812, there were 3 earthquakes that were larger than the 1906 San Francisco earthquake, and there were about 2,000 event recorded in Nashville, TN which is quite a distance from the perceived epicenter. There was damage recorded in Charleston and church bells rang in Boston. Now THAT is an earthquake.

There are some changes coming down the pike, but they are not here yet. You can follow the trends by watching what comes up on BSSConline.org. USGS is very methodically vetting the changes.

Regards, Harold Sprague

From: sgordin@sgeconsulting.com
To: seaint@seaint.org
Subject: seismic forces
Date: Mon, 24 Nov 2008 12:19:26 -0800

List,

Based on the 2006 IBC (ASCE07-05), the seismic accelerations for Hayward, CA (right on the Hayward fault) appear to be about 60% lower than those for Sikestone, MO, and about the same as for Summerville, SC.

Historic (1812 and 1886) considerations aside, any comments?

V. Steve Gordin, SE
Irvine CA

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Progressive collapse

Thank for your feedback on the software currently use for progressive collapse. We will looking into using SAP2000 or LSDYNA for the project.

Best regards.

Access your email online and on the go with Windows Live Hotmail. Sign up today.

Re: seismic forces

On Mon, Nov 24, 2008 at 11:33 PM, Christopher Wright
<chrisw@skypoint.com> wrote:
>
> On Nov 24, 2008, at 7:24 PM, Harold Sprague wrote:
>
>> between December 1811 and May 1812, there were 3 earthquakes that were
>> larger than the 1906 San Francisco earthquake, and there were about 2,000
>> event recorded in Nashville, TN which is quite a distance from the perceived
>> epicenter. There was damage recorded in Charleston and church bells rang in
>> Boston. Now THAT is an earthquake.
>
> Damn right. It changed the course of the Mississippi. In 1812 there weren't
> many real cities west of the Appalachian mountains--no Nashville, no
> Memphis, no Chicago, no Kansas City. The next New Madrid quake is likely to
> spoil your whole weekend.
>
> Christopher Wright P.E.

Walter Jon Williams wrote a fictional account of a NM event happening "Today".

http://en.wikipedia.org/wiki/The_Rift_(novel)

Good read.

Mike Jones

RE: seismic forces

The other factor that plays into the New Madrid and Charleston-area ground motions is that neither event (1812 or 1886) was recorded by seismographs. So, the “official” magnitudes are largely estimates based on the observed damage patterns (with a little bit of geology thrown in). And the average of the several estimates was weighted towards the higher guesses. So the seismic hazard in both places is essentially based on a 2%-in-50 chance of exceeding an M7.1 to M7.3 earthquake, which makes the MCE for those two areas a pretty damn big earthquake—ignoring the possibility that the 1812 and 1886 events ARE the 2500-year events. And, because the CEUS ground motions are not deterministically capped, the ground motions therefore come out equal to or larger than those along the well-known California faults.

Regards,

Gary

Attend the 2009 International Builders' Show
January 20-23, 2009, Las Vegas, NV
www.BuildersShow.com

From: Harold Sprague [mailto:spraguehope@hotmail.com]
Sent: Monday, November 24, 2008 8:25 PM
To: seaint@seaint.org
Subject: RE: seismic forces

From: sgordin@sgeconsulting.com
To: seaint@seaint.org
Subject: seismic forces
Date: Mon, 24 Nov 2008 12:19:26 -0800

List,

Historic (1812 and 1886) considerations aside, any comments?

V. Steve Gordin, SE
Irvine CA

Proud to be a PC? Show the world. Download the “I’m a PC” Messenger themepack now. Download now.

Monday, November 24, 2008

Re: seismic forces

On Nov 24, 2008, at 7:24 PM, Harold Sprague wrote:

> between December 1811 and May 1812, there were 3 earthquakes that
> were larger than the 1906 San Francisco earthquake, and there were
> about 2,000 event recorded in Nashville, TN which is quite a
> distance from the perceived epicenter. There was damage recorded
> in Charleston and church bells rang in Boston. Now THAT is an
> earthquake.
Damn right. It changed the course of the Mississippi. In 1812 there
weren't many real cities west of the Appalachian mountains--no
Nashville, no Memphis, no Chicago, no Kansas City. The next New
Madrid quake is likely to spoil your whole weekend.

Re: Use old 2D autocad typical details when putting plans together in Revit?

Scott,

Yes that's exactly right. You can use your regular details from autocad, but the framing plans are in Revit.

You can also cut sections in Revit to get basic geometry of a detail you'd like to make, then export to autocad and finish off.

If you are familiar with Etabs or Risa, Revit is very similar to building models in those programs.

I took a 3 day course in Revit training that was very helpful, but you can do pretty good yourself if you get the Autodesk Essentials training book for Structure 2009. It is a book with a step by step tutorial with a companion CD.

It would be better if they had videos for free like the Etabs guys have on their website, but then the training schools would be out of business.

Bottom line, it's easier than you think, but making the plans look nice takes a little more getting used to.

-gm

On Mon, Nov 24, 2008 at 5:26 PM, Haan, Scott M POA <Scott.M.Haan@usace.army.mil> wrote:

I've never used a BIM model for putting together plans. I am getting thrown
into a project using Revit where the 65% plans are due to soon, without
training of course.

I haven't talked with anyone directly about their detail sheets when they use
BIM models for their plans. It seems like you don't want to draw all your
connections, slab on grade details etc... in 3D model space and put your text
for them in paper space. It kind of defeats the purpose of typical details.

Do people use their old 2D Autocad typical connection details and just use
the BIM model for the framing and foundation plans?

Thanks.

******* ****** ******* ******** ******* ******* ******* ***
* 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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* Questions to seaint-ad@seaint.org. Remember, any email you
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Use old 2D autocad typical details when putting plans together in Revit?

I've never used a BIM model for putting together plans. I am getting thrown
into a project using Revit where the 65% plans are due to soon, without
training of course.

I haven't talked with anyone directly about their detail sheets when they use
BIM models for their plans. It seems like you don't want to draw all your
connections, slab on grade details etc... in 3D model space and put your text
for them in paper space. It kind of defeats the purpose of typical details.

Do people use their old 2D Autocad typical connection details and just use
the BIM model for the framing and foundation plans?

Thanks.

RE: seismic forces

From: sgordin@sgeconsulting.com
To: seaint@seaint.org
Subject: seismic forces
Date: Mon, 24 Nov 2008 12:19:26 -0800

List,

Historic (1812 and 1886) considerations aside, any comments?

V. Steve Gordin, SE
Irvine CA

Proud to be a PC? Show the world. Download the "I'm a PC" Messenger themepack now. Download now.

Re: seismic forces

Gordon and Thomas,

The discussion in the 2003 NEHRP is indeed very informative and concise.

However astronomical the return period is, it has very practical consequence:

the code-compliant design for identical structures in Hayward and Sikestone, will have the forces for the latter location 1.67 time higher than those for the former.

As for being "hosed" - imagine the implications for retrofit etc. I also wonder if the plancheck process in Minnesota and South Carolina is as rigorous as in California.

V. Steve Gordin, SE
Irvine CA

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

From: Gordon Goodell

To: seaint@seaint.org

Sent: Monday, November 24, 2008 14:24

Subject: RE: seismic forces

10% has been abandoned; now it's 2/3 of 2%, 50 yrs. That's a 2500 yr return! So in California, where the frequency of a design event is more like a few hundred years, known faults that have enough historical data use 1 ½ x the characteristic event. There's a good, brief discussion of the rationale behind this change in the commentary to the Ground Motion chapter of the 2003 NEHRP.

regards,

Gordon Goodell

From: David Topete [mailto:d.topete73@gmail.com]
Sent: Monday, November 24, 2008 2:39 PM
To: seaint@seaint.org
Subject: Re: seismic forces

Aren't the accelerations based on the 10% at 50 year event? So, that means New Madrid and Summerville have the potential for very large accelerations for the 475-year event. The fact that the Hayward fault (which I live on) is more active is because you have the Pacific plate rubbing constantly on the North American plate, or vice versa. If I'm off, I'm sure I'll be corrected. That's my just my view from basement...

On Mon, Nov 24, 2008 at 12:19 PM, SGE Structural <sgordin@sgeconsulting.com> wrote:

List,

Based on the 2006 IBC (ASCE07-05), the seismic accelerations for Hayward, CA (right on the Hayward fault) appear to be about 60% lower than those for Sikestone, MO, and about the same as for Summerville, SC.

Historic (1812 and 1886) considerations aside, any comments?

V. Steve Gordin, SE
Irvine CA

--
David Topete, SE

RE: seismic forces

Steve,

As Gordon has pointed out, most of the U.S. seismic parameters are based on an effective 2500 year return period which were derived from probabilistic studies and formula. As you get to the western part of the U.S. where we have known faults these values were transitioned with deterministic values based on actual seismic data (i.e. seismic acceleration recordings). It is probably closer to say your seismic values are about the same (may be may be not, I did not look them up) and the people in Sikestone and Summerville are now getting hosed.

Thomas Hunt, S.E.
Fluor

"Gordon Goodell" <GordonGoodell@harmonydesigninc.com>
11/24/2008 02:24 PM
Please respond to seaint

To	<seaint@seaint.org>
cc
Subject	RE: seismic forces

10% has been abandoned; now it's 2/3 of 2%, 50 yrs. That's a 2500 yr return! So in California, where the frequency of a design event is more like a few hundred years, known faults that have enough historical data use 1 ½ x the characteristic event. There's a good, brief discussion of the rationale behind this change in the commentary to the Ground Motion chapter of the 2003 NEHRP.

regards,
Gordon Goodell

From: David Topete [mailto:d.topete73@gmail.com]
Sent: Monday, November 24, 2008 2:39 PM
To: seaint@seaint.org
Subject: Re: seismic forces

Aren't the accelerations based on the 10% at 50 year event? So, that means New Madrid and Summerville have the potential for very large accelerations for the 475-year event. The fact that the Hayward fault (which I live on) is more active is because you have the Pacific plate rubbing constantly on the North American plate, or vice versa. If I'm off, I'm sure I'll be corrected. That's my just my view from basement...
On Mon, Nov 24, 2008 at 12:19 PM, SGE Structural <sgordin@sgeconsulting.com> wrote:
List,

Based on the 2006 IBC (ASCE07-05), the seismic accelerations for Hayward, CA (right on the Hayward fault) appear to be about 60% lower than those for Sikestone, MO, and about the same as for Summerville, SC.
Historic (1812 and 1886) considerations aside, any comments?

V. Steve Gordin, SE
Irvine CA

--
David Topete, SE

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RE: seismic forces

10% has been abandoned; now it’s 2/3 of 2%, 50 yrs. That’s a 2500 yr return! So in California, where the frequency of a design event is more like a few hundred years, known faults that have enough historical data use 1 ½ x the characteristic event. There’s a good, brief discussion of the rationale behind this change in the commentary to the Ground Motion chapter of the 2003 NEHRP.

regards,

Gordon Goodell

From: David Topete [mailto:d.topete73@gmail.com]
Sent: Monday, November 24, 2008 2:39 PM
To: seaint@seaint.org
Subject: Re: seismic forces

Aren't the accelerations based on the 10% at 50 year event? So, that means New Madrid and Summerville have the potential for very large accelerations for the 475-year event. The fact that the Hayward fault (which I live on) is more active is because you have the Pacific plate rubbing constantly on the North American plate, or vice versa. If I'm off, I'm sure I'll be corrected. That's my just my view from basement...

On Mon, Nov 24, 2008 at 12:19 PM, SGE Structural <sgordin@sgeconsulting.com> wrote:

List,

Historic (1812 and 1886) considerations aside, any comments?

V. Steve Gordin, SE
Irvine CA

--
David Topete, SE

RE: Progressive collapse

Return Receipt

Your RE: Progressive collapse
document:

was Tom Hunt/AV/FD/FluorCorp
received
by:

at: 11/24/2008 13:40:32 PST

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Re: seismic forces

On Mon, Nov 24, 2008 at 12:19 PM, SGE Structural <sgordin@sgeconsulting.com> wrote:

List,

Based on the 2006 IBC (ASCE07-05), the seismic accelerations for Hayward, CA (right on the Hayward fault) appear to be about 60% lower than those for Sikestone, MO, and about the same as for Summerville, SC.

Historic (1812 and 1886) considerations aside, any comments?

V. Steve Gordin, SE
Irvine CA

--
David Topete, SE

RE: Progressive collapse

Cairo:

Our firm has also used on numerous occasions SAP2000 Non-Linear for the analysis of actual steel moment frames needing to be designed and checked for DoD and GSA progressive collapse requirements. For even more refined (nitty gritty stuff), we have been involved with projects using LSDYNA.

Feel free to call me directly for more details. Hope this is helpful.

Take Care,

Henry Gallart, S.E.

Sr. Vice President

SidePlate Systems, Inc.

23332 Mill Creek Drive, Ste 205
Laguna Hills, CA 92653

Tel: 949-305-7889

Tel: 800-475-2077

Fax: 949-305-6395

www.sideplate.com

From: cairo briceño [mailto:cobdel@hotmail.com]
Sent: Friday, November 21, 2008 4:02 PM
To: seaint@seaint.org
Subject: Progressive collapse

Dear list members,

I have a simple question. Any suggestion about the best software to perform a progressive collapse analysis? The structure is a architectural stylish high rise building with all the irregularities you can imagine.

Thank you for advise.

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seismic forces

List,

Historic (1812 and 1886) considerations aside, any comments?

V. Steve Gordin, SE
Irvine CA

RE: Progressive collapse

I believe the software PERFORM developed by Computers and Structures does Progressive Collapse Analysis. We are just beginning to use this Software but I have heard many good things about it specially with regard to non-linear analysis of structural performance in design offices and the support system. I have to disclose that this program is developed by my colleague and friend Professor Powell of UC Berkeley. You may want to try this site for more information http://www.csiberkeley.com/products_PERFORM.html.

Of course, more high end software, such as DYTRAN and NASTRAN (both from www.mscsoftware.com) can be used to investigate progressive collapse. We have used these extensively and for about 8 years and are very satisfied with their capabilities and the support system.

Hope this helps.

Abolhassan Astaneh-Asl, Ph.D., P.E.,
Professor and Consultant on Structural Engineering,
Earthquake Engineering and Protection of Structures against Impact and Blast
------------------------------------------------

From: "Conrad Harrison" <sch.tectonic@bigpond.com>
To: <seaint@seaint.org>
Subject: RE: Progressive collapse

As far as I am aware there is no commercial software at present for
progressive collapse, just research. Also progressive collapse is more a
qualitative issue than quantitative.

Any frame analysis software with a programmable interface would be helpful
for the analysis. Without the programmable interface simply copy the model,
delete the members and change the loads. With a programmable interface
automatically delete members and change loads using the one model, and
search for the critical condition.

Regards

Conrad Harrison

B.Tech (mfg & mech), MIIE, gradTIEAust

mailto:sch.tectonic@bigpond.com

Adelaide

South Australia

Re: Seismic code for Iraq

When I initially said nothing was listed for Iraq, i was just looking at table for wind and snow loading... I found my error just as i clicked "send." Good luck.

On Fri, Nov 21, 2008 at 5:05 PM, Gautam Manandhar <Gautam_Manandhar@ci.richmond.ca.us> wrote:

David:

Thank you for your response. The UFC manual gives Ss and S1 on Table D-2 for Baghdad and Basra – the project is in Baghdad. At least, that is a start.

Gautam

From: David Topete [mailto:d.topete73@gmail.com]
Sent: Friday, November 21, 2008 3:18 PM
To: seaint@seaint.org
Subject: Re: Seismic code for Iraq

but they don't show anythign for iraq... great... sorry. Good luck, gautam.

On Fri, Nov 21, 2008 at 3:16 PM, David Topete <d.topete73@gmail.com> wrote:

it's UFC 3-310-01

On Fri, Nov 21, 2008 at 3:15 PM, David Topete <d.topete73@gmail.com> wrote:

There is a UFC document listing seismic and wind criteria for global military installations. I Believe it is UFC 3-310-00. Search http://www.wbdg.org/ccb/browse_cat.php?o=29&c=4,

On Fri, Nov 21, 2008 at 2:50 PM, Gautam Manandhar <Gautam_Manandhar@ci.richmond.ca.us> wrote:

List Members:

I have been approached to provide structural design service for a project in Iraq. I am looking for some info on lateral design requirements. I presume the US Army would have some sort of design manual for Iraq. Is anybody aware of one – I would appreciate a web link to such a document.

Does anyone have access to the wide flange steel beam section properties – the drawings call for HEA240, HEA300, and IPE360. I believe these conform to European standards.

Gautam

--
David Topete, SE

--
David Topete, SE

--
David Topete, SE

--
David Topete, SE

RE: OCBF Requirements

Return Receipt

Your RE: OCBF Requirements
document:

was RHoltham@CBI.com
received
by:

at: 11/24/2008 11:17:15 AM

RE: OCBF Requirements

Return Receipt

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document:

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Sunday, November 23, 2008

RE: Progressive collapse

As Conrad said, any commercial software can do the regular progressive collapse. In the FEMA 439 project Degenkolb employed SAP 2000 for progressive collapse.

LSDYNA is another program that can accommodate progressive collapse if higher degrees of sophistication are required. There are also commercially available programs such as:
http://www.appliedscienceint.com/Home.asp

Regards, Harold Sprague

From: sch.tectonic@bigpond.com
To: seaint@seaint.org
Subject: RE: Progressive collapse
Date: Mon, 24 Nov 2008 11:20:16 +1030

As far as I am aware there is no commercial software at present for progressive collapse, just research. Also progressive collapse is more a qualitative issue than quantitative.

Any frame analysis software with a programmable interface would be helpful for the analysis. Without the programmable interface simply copy the model, delete the members and change the loads. With a programmable interface automatically delete members and change loads using the one model, and search for the critical condition.

Regards

Conrad Harrison

B.Tech (mfg & mech), MIIE, gradTIEAust

mailto:sch.tectonic@bigpond.com

Adelaide

South Australia

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RE: Progressive collapse

As far as I am aware there is no commercial software at present for progressive collapse, just research. Also progressive collapse is more a qualitative issue than quantitative.

Any frame analysis software with a programmable interface would be helpful for the analysis. Without the programmable interface simply copy the model, delete the members and change the loads. With a programmable interface automatically delete members and change loads using the one model, and search for the critical condition.

Regards

Conrad Harrison

B.Tech (mfg & mech), MIIE, gradTIEAust

mailto:sch.tectonic@bigpond.com

Adelaide

South Australia