Structural Engineering: 2007-08-19

Saturday, August 25, 2007

RE: 2006 IBC Wind Load question

Dennis:

In my experience, unless the local jurisdiction completely modified the wind provisions for use in their local building code, the only item that you might get from the local code official is the wind speed. But, that would only really likely happen in areas along the East and South Coasts (i.e. hurricane zones where the wind speed maps get a little tough to read...it is good to check with the local official as to what wind speed to use...OR in special wind regions typically in mountous regions). The vast majority of the US is 90 mph (with the exception of the three West Coast states that magically have 85 mph winds when you cross the border into those states).

The only other thing that the code official MIGHT dictate is the Exposure Category, but that has been EXTREMELY rare in my experience.

Beyond that, there should be no difference between getting values off the map or getting them from the code official. The process is still the same...unless they have replaced the typical IBC/ASCE 7 wind provisions with something else or modified those provisions extensively.

Point is that I don't see a difference between getting wind parameters from a code official vs. a map in terms of the process for determining the wind loads. It is the same process...it is just that first little piece of data used to input into the process might differ.

Regards,

Scott

Adrian, MI

-----Original Message-----
From: Dennis Wish [mailto:dennis.wish@verizon.net]
Sent: Saturday, August 25, 2007 8:49 PM
To: seaint@seaint.org
Subject: 2006 IBC Wind Load question

I’ve discussed the design of wind loads for the next generation of IBC codes that California will adopt in 2008 to replace the 97 UBC. As most of you who use the UBC or California building code are aware, the 97 UBC is a fairly straight forward method to determine wind design.

Most of the engineers I’ve spoken to who are in IBC country have mentioned that they rarely use more than the windward side of loading and have not used the more extensive load design methods that check windward, leeward, uplift on eaves and on interior roof areas (where there is a percentage of space exposed to consistent wind loads). I do check uplift on the eaves but only if the uplift occurs on a very light roof such as asphalt shingle or metal. When clay tile is use and the exterior dead load exceeds a lightweight tile then I find that the roof weight rarely shows that uplift occurs. Of course I do not live in a high wind area that exceeds 90-psf wind gust.

My concern is that I have to add the wind design into the next version of MultiLat and as many of you know I have been suffering with the learning process based on the latest ASCE wind load design methods.

My question is whether or not you think that the values we need to design to will be provided by the local municipality in which you will design your structure or if you will be required to work everything out by maps and government references. Currently the building department sets the limits we design to and I’ve never had to rely on reference maps from government references.

Have any of you worked up a worksheet design method of the simplified wind load conditions to be used with the 2006 IBC and are willing to share it with me to help me understand the steps. I’ve been told that the design wind loads can be designed more like the 97 UBC if the design values are supplied by the building official. I wish to add this to MultiLat, but would prefer to use a method based on inputting local conditions provided by the building department your structure is designed for.

I would like some advices as to how many of you plan to design wind loads in the 2006 IBC and what you have done in the past AND what you expect to do in the next code cycle. If you are willing to share your ideas with me, I would be greatly appreciative. However, remember that I am in the mindset that whatever I create is submitted for public domain so that others can save a bit of time.

Thanks,

Dennis

No virus found in this outgoing message.
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2006 IBC Wind Load question

I’ve discussed the design of wind loads for the next generation of IBC codes that California will adopt in 2008 to replace the 97 UBC. As most of you who use the UBC or California building code are aware, the 97 UBC is a fairly straight forward method to determine wind design.

Most of the engineers I’ve spoken to who are in IBC country have mentioned that they rarely use more than the windward side of loading and have not used the more extensive load design methods that check windward, leeward, uplift on eaves and on interior roof areas (where there is a percentage of space exposed to consistent wind loads). I do check uplift on the eaves but only if the uplift occurs on a very light roof such as asphalt shingle or metal. When clay tile is use and the exterior dead load exceeds a lightweight tile then I find that the roof weight rarely shows that uplift occurs. Of course I do not live in a high wind area that exceeds 90-psf wind gust.

My concern is that I have to add the wind design into the next version of MultiLat and as many of you know I have been suffering with the learning process based on the latest ASCE wind load design methods.

My question is whether or not you think that the values we need to design to will be provided by the local municipality in which you will design your structure or if you will be required to work everything out by maps and government references. Currently the building department sets the limits we design to and I’ve never had to rely on reference maps from government references.

Have any of you worked up a worksheet design method of the simplified wind load conditions to be used with the 2006 IBC and are willing to share it with me to help me understand the steps. I’ve been told that the design wind loads can be designed more like the 97 UBC if the design values are supplied by the building official. I wish to add this to MultiLat, but would prefer to use a method based on inputting local conditions provided by the building department your structure is designed for.

I would like some advices as to how many of you plan to design wind loads in the 2006 IBC and what you have done in the past AND what you expect to do in the next code cycle. If you are willing to share your ideas with me, I would be greatly appreciative. However, remember that I am in the mindset that whatever I create is submitted for public domain so that others can save a bit of time.

Thanks,

Dennis

Reference needed

I asked this same question of a close friend, but thought I might get a wider range of references by posting this notice on the SEAINT List.

I have a need to write my own spreadsheet tool or TEDDS template that will allow me to design a spread footing with multiple eccentric loads (say two or three columns that share the same pad that might be common in custom home remodels). One of the problems stems from doweling two slab on grades together where a room addition is added and removing a wall to allow a pass-through. In some cases the framing is such that the reaction at each header column exceeds the soil bearing capacity of a typical turned down 12-inch wide continuous slab on grade foundation when considering the maximum distribution on the foundation should not exceed a 4:1 ratio. So if the combined reaction is 6-kips and the soil bearing pressure is only 1000 psf then the maximum bearing pressure you can distribute over the length of the slab foundation is 4:1 or 4-kips. However, if you provide a similar turn-down edge to the adjacent new slab on grade (rather the more common 8-inch thick slab edge that is used to dowel the two together) then you can double the bearing pressure by considering the width of the combined slab foundation to be 2-feet in width and the 4:1 max ratio will allow for an 8-kip reaction. The problem is that the column now has an eccentricity that must be considered.

The second condition is if the new and the existing are independently supported on two columns where the framing is parallel to one another. This provides two columns on two slab edges that are doweled together or on one rectangular (or square pad) with each column eccentric and not necessarily balanced in loading.

To be frank, after 21 years in private practice, I’ve relied on software to do the work and while my intuition is good, I would like to relearn my skills and go back to the basics so that I can write a spreadsheet for up to four of six eccentric loads on one pad foundation.

I’m looking for a back to basic soils or foundation design manual to help me work out the algorithms that I need to write the spreadsheet. I think I understand how to find the center of mass based on the load distributions but would like to compare it against a text. My foundation design manuals that I used in school seem more than complicated and I am looking for something fairly straight forward.

If I would prefer, I would also like the text to cover other types of foundations; continuous wall foundations; friction piles, spread footings that are used installed below an existing foundation (remodeling situation); distribution of shear from eccentric loading conditions where new foundations are doweled or added to the existing etc.

Please post your favorite references for foundation design. I think the Retaining wall reference published by Huge Brooks is the best I’ve seen and I use this as a primer to refresh my memory on retaining wall design, but for the other conditions I am seeking a text rather than a reference for a computer program that will do the work for me.

One of the problems with relying on computer software that I take for granted because I write most of my own tools is writing one that you have been used to designing by shortcut (for example a grade beam that takes the moment from each end at the base of a moment frame). I’ve designed these using a half page or less shortcut, but I want to restore my understanding of the basics as I have always done with code programs such as MultiLat™ that assisted me to understand what was in the mind of the code writer while I was recreating the spreadsheet.

At nearly sixty years old, I am not too proud to want to return to the basics and admit that I forgot some of my elemental skills. Help me restore my memory by suggesting the reference that you use when you need to do an analysis manually that you have not done for a long time.

Thanks

Dennis

Dennis S. Wish, PE

California Professional Engineering – C 41250 Exp 03/31/09

Structural Engineering Consultant

La Quinta California

FW: Test

Second try

From: Gunnar H. Isleifsson [mailto:ghi@pc.dk]
Sent: 26 August 2007 00:52
To: seaint@seaint.org
Subject: Test

No messages since August 14th???

Gunnar Hafsteinn Isleifsson

Denmark

RE: Anchor Bolts

With oversized holes in the baseplate, anchor bolts would not work for resisting the shear forces. Shear lugs would be required. Another option would be shear friction if the vertical force is always down. But with such a high shear load I do not think you could develop enough friction.

Shear lugs would also allow you to reduce the bolt diameter and use lower grade material. With such a high grade material the embedment depth would be significant to develop the anchor bolt.

Which force is vertical? Is it always down or is there an uplift?

Gary Loomis, PE

Master Engineers and Designers

Gents:

I have this scenario; a support reaction F x = 172 Kips, F y = 100 kips F z = 21 kips

Due to space restrictions I can only fit 4 - 1 ½" diameter anchor bolts.

What I'm planning to meet this requirement is to use a F1554 GR 105, and a shear lug. Can anyone suggest if this kind of Grade of fastener

Is good for resisting a high shear load?

Engr. Julius Micayas

P.E. license no.32969

Senior Lead Structural Engineer

Phone - 504-841-3014 (direct)

504 837-5275 (office)

Fax - 504-837-2986

e-mail: jmicayas@riverconsulting.com

Friday, August 24, 2007

Re: Job Opportunity - OT

Marlou Rodriguez wrote:

Message

If you want to be wealthy, then you go out and work for a Tech company

If you make this statement to a "tech guy," stand back. A large blast of wind is likely to result owing to unrestrained laughter.

I think it is very much a misconception that "tech guys" are all highly paid, especially relative to what folks in our profession make. It might have been true a decade ago, when the sudden explosion of "distributed computing" made designations like "Microsoft Certified Engineer" easily as marketable as an MBA from a highly-rated B-school.

But not anymore. Now, these folks are a commodity. My sister works for the Federal Courts system and my brother, for a large regional bank, both in Birmingham, Alabama. They are very accomplished, my sister an expert in .NET stuff and my brother with Java, SQL, etc., the major e-commerce/e-banking platforms. They each do all right, but no one is confusing them with wealthy, by any stretch of the imagination.

Ironically, I'm making almost as much right now as the both of them put together.

Re: Guano and Bridge Failure

On Aug 24, 2007, at 3:46 PM, Mark Deardorff wrote:

> Here you go. I saw this and thought it was interesting.
In a related vein can someone tell me how the bridge worked
structurally. I've guessed that the center span (the one that went in
the river) was was supported off cantilevered end spans like the
Firth of Tay bridge in Scotland. The Wiki article <http://
en.wikipedia.org/wiki/I-35W_Mississippi_River_bridge> describes it as
a deck-arch truss bridge which seems to be about the same idea on the
center span carries loads as an arch. Does anyone know how the
structure works.

When I saw the video of the collapse, it looked like both ends of the
center span dropped pretty much simultaneously, with the south end
dropping slightly ahead of the north end. I figured the center span
support connections let go and the end spans just tipped outward
because the load wasn't balanced. I was really only guessing, though.
Does anyone have any insight into the sequence of the collapse? Apart
from a long discussion on the corrosive properties of pigeon droppings.
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/~chrisw/

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RE: Guano and Bridge Failure

What's the matter? You don't have to be an engineer to enjoy reading about guano do you? In fact, some engineers do not enjoy it either.

RLH

-----Original Message-----
From: RUSSELL SCHMIDT [mailto:BAGMAN13@MSN.COM]
Sent: Friday, August 24, 2007 3:01 PM
To: seaint@seaint.org; Garner, Robert
Subject: Re: Guano and Bridge Failure

Does anyone out there know how to cancel my subscription to this e-mail service. My secretary signed me up thinking she was helping. I am not an engineer and have no reason to see these e-mail. HELP!!!   Thanks.

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

From: Garner, Robert

To: Garner, Robert ; seaint@seaint.org

Sent: Friday, August 24, 2007 3:46 PM

Subject: RE: Guano and Bridge Failure

'Scuse me, that would be more like 60 psf (I'm currently designing
something for a 2' snow and that influenced me).

-----Original Message-----
From: Garner, Robert [mailto:rgarner@moffattnichol.com]
Sent: Friday, August 24, 2007 2:43 PM
To: seaint@seaint.org
Subject: RE: Guano and Bridge Failure

------------------------------------------------------------------------
--
Your following message has been delivered to the list
seaint@seaint.org at 14:43:17 on 24 Aug 2007.
------------------------------------------------------------------------
--

If that guano was 100% saturated, that could add over 100 psf load.
Wow! Something to think about.

Bob

-----Original Message-----
From: Chance, Acie [mailto:AChance@lacsd.org]

Sent: Friday, August 24, 2007 2:32 PM
To: seaint@seaint.org
Subject: RE: Guano and Bridge Failure

     Years ago I worked for a company who designed and built canopies
for gas stations. There was a failure of a single column canopy as the
pigeons liked one side of the canopy more then the other. The side they
liked had more then a foot of pigeon guano built up on the roof deck.
If memory serves me correctly the column bent over to the point it had
to be replaced.

Acie Chance

-----Original Message-----
From: Mark Deardorff [mailto:mark@rstavares.com]
Sent: Friday, August 24, 2007 1:47 PM
To: seaint@seaint.org
Subject: Guano and Bridge Failure

Here you go. I saw this and thought it was interesting.

http://www.foxnews.com/story/0,2933,294153,00.html

Mark E. Deardorff, SE

R & S Tavares Associates, Inc
9815 Carroll Canyon Road
Suite 206
San Diego, CA 92131
Phone: 858-444-3344
Phone: 209-863-8928
mark@rstavares.com
www.rstavares.com

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Re: Anchor Bolts

Julius,

Shear lug(s) is your best bet, anchor bolts are not that good in taking the shear, especially, when you have so few of those. I would not recommend to combine the action of both.

V. Steve Gordin, SE
Irvine CA

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

From: Micayas, Julius

To: seaint@seaint.org

Sent: Friday, August 24, 2007 15:20

Subject: Anchor Bolts

Gents:

I have this scenario; a support reaction F x = 172 Kips, F y = 100 kips F z = 21 kips

Due to space restrictions I can only fit 4 – 1 ½" diameter anchor bolts.

What I'm planning to meet this requirement is to use a F1554 GR 105, and a shear lug. Can anyone suggest if this kind of Grade of fastener

Is good for resisting a high shear load?

Engr. Julius Micayas

P.E. license no.32969

Senior Lead Structural Engineer

Phone - 504-841-3014 (direct)

504 837-5275 (office)

Fax - 504-837-2986

e-mail: jmicayas@riverconsulting.com

Re: Guano and Bridge Failure

Talking about rescue...

To subscribe (no fee) or UnSubscribe, please go to: * http://www.seaint.org/sealist1.asp

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

From: RUSSELL SCHMIDT

To: seaint@seaint.org ; Garner, Robert

Sent: Friday, August 24, 2007 15:01

Subject: Re: Guano and Bridge Failure

Does anyone out there know how to cancel my subscription to this e-mail service. My secretary signed me up thinking she was helping. I am not an engineer and have no reason to see these e-mail. HELP!!!   Thanks.

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Anchor Bolts

Gents:

I have this scenario; a support reaction F x = 172 Kips, F y = 100 kips F z = 21 kips

Due to space restrictions I can only fit 4 – 1 ½” diameter anchor bolts.

What I’m planning to meet this requirement is to use a F1554 GR 105, and a shear lug. Can anyone suggest if this kind of Grade of fastener

Is good for resisting a high shear load?

Engr. Julius Micayas

P.E. license no.32969

Senior Lead Structural Engineer

Phone - 504-841-3014 (direct)

504 837-5275 (office)

Fax - 504-837-2986

e-mail: jmicayas@riverconsulting.com

Re: Guano and Bridge Failure

Does anyone out there know how to cancel my subscription to this e-mail service. My secretary signed me up thinking she was helping. I am not an engineer and have no reason to see these e-mail. HELP!!! Thanks.

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

From: Garner, Robert

To: Garner, Robert ; seaint@seaint.org

Sent: Friday, August 24, 2007 3:46 PM

Subject: RE: Guano and Bridge Failure

'Scuse me, that would be more like 60 psf (I'm currently designing
something for a 2' snow and that influenced me).

-----Original Message-----
From: Garner, Robert [mailto:rgarner@moffattnichol.com]
Sent: Friday, August 24, 2007 2:43 PM
To: seaint@seaint.org
Subject: RE: Guano and Bridge Failure

------------------------------------------------------------------------
--
Your following message has been delivered to the list
seaint@seaint.org at 14:43:17 on 24 Aug 2007.
------------------------------------------------------------------------
--

If that guano was 100% saturated, that could add over 100 psf load.
Wow! Something to think about.

Bob

-----Original Message-----
From: Chance, Acie [mailto:AChance@lacsd.org]

Sent: Friday, August 24, 2007 2:32 PM
To: seaint@seaint.org
Subject: RE: Guano and Bridge Failure

     Years ago I worked for a company who designed and built canopies
for gas stations. There was a failure of a single column canopy as the
pigeons liked one side of the canopy more then the other. The side they
liked had more then a foot of pigeon guano built up on the roof deck.
If memory serves me correctly the column bent over to the point it had
to be replaced.

Acie Chance

-----Original Message-----
From: Mark Deardorff [mailto:mark@rstavares.com]
Sent: Friday, August 24, 2007 1:47 PM
To: seaint@seaint.org
Subject: Guano and Bridge Failure

Here you go. I saw this and thought it was interesting.

http://www.foxnews.com/story/0,2933,294153,00.html

Mark E. Deardorff, SE

R & S Tavares Associates, Inc
9815 Carroll Canyon Road
Suite 206
San Diego, CA 92131
Phone: 858-444-3344
Phone: 209-863-8928
mark@rstavares.com
www.rstavares.com

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The information contained in the e-Mail, including any accompanying
documents or attachments, is from Moffatt & Nichol and is intended only
for the use of the individual or entity named above, and is privileged
and confidential. If you are not the intended recipient, be aware that
any disclosure, dissemination, distribution, copying or use of the
contents of this message is strictly prohibited. If you received this
message in error, please notify us.

******* ****** ******* ******** ******* ******* ******* ***
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*   This email was sent to you via Structural Engineers
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RE: Guano and Bridge Failure

'Scuse me, that would be more like 60 psf (I'm currently designing
something for a 2' snow and that influenced me).

-----Original Message-----
From: Garner, Robert [mailto:rgarner@moffattnichol.com]
Sent: Friday, August 24, 2007 2:43 PM
To: seaint@seaint.org
Subject: RE: Guano and Bridge Failure

------------------------------------------------------------------------
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Your following message has been delivered to the list
seaint@seaint.org at 14:43:17 on 24 Aug 2007.
------------------------------------------------------------------------
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If that guano was 100% saturated, that could add over 100 psf load.
Wow! Something to think about.

Bob

-----Original Message-----
From: Chance, Acie [mailto:AChance@lacsd.org]

Sent: Friday, August 24, 2007 2:32 PM
To: seaint@seaint.org
Subject: RE: Guano and Bridge Failure

Years ago I worked for a company who designed and built canopies
for gas stations. There was a failure of a single column canopy as the
pigeons liked one side of the canopy more then the other. The side they
liked had more then a foot of pigeon guano built up on the roof deck.
If memory serves me correctly the column bent over to the point it had
to be replaced.

Acie Chance

-----Original Message-----
From: Mark Deardorff [mailto:mark@rstavares.com]
Sent: Friday, August 24, 2007 1:47 PM
To: seaint@seaint.org
Subject: Guano and Bridge Failure

Here you go. I saw this and thought it was interesting.

http://www.foxnews.com/story/0,2933,294153,00.html

Mark E. Deardorff, SE

R & S Tavares Associates, Inc
9815 Carroll Canyon Road
Suite 206
San Diego, CA 92131
Phone: 858-444-3344
Phone: 209-863-8928
mark@rstavares.com
www.rstavares.com

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RE: Guano and Bridge Failure

If that guano was 100% saturated, that could add over 100 psf load.
Wow! Something to think about.

Bob

-----Original Message-----
From: Chance, Acie [mailto:AChance@lacsd.org]
Sent: Friday, August 24, 2007 2:32 PM
To: seaint@seaint.org
Subject: RE: Guano and Bridge Failure

Acie Chance

-----Original Message-----
From: Mark Deardorff [mailto:mark@rstavares.com]
Sent: Friday, August 24, 2007 1:47 PM
To: seaint@seaint.org
Subject: Guano and Bridge Failure

Here you go. I saw this and thought it was interesting.

http://www.foxnews.com/story/0,2933,294153,00.html

Mark E. Deardorff, SE
R & S Tavares Associates, Inc
9815 Carroll Canyon Road
Suite 206
San Diego, CA 92131
Phone: 858-444-3344
Phone: 209-863-8928
mark@rstavares.com
www.rstavares.com

******* ****** ****** ****** ******* ****** ****** ********

The information contained in the e-Mail, including any accompanying documents or attachments, is from Moffatt & Nichol and is intended only for the use of the individual or entity named above, and is privileged and confidential. If you are not the intended recipient, be aware that any disclosure, dissemination, distribution, copying or use of the contents of this message is strictly prohibited. If you received this message in error, please notify us.

RE: Guano and Bridge Failure

Years ago I worked for a company who designed and built canopies for gas stations. There was a failure of a single column canopy as the pigeons liked one side of the canopy more then the other. The side they liked had more then a foot of pigeon guano built up on the roof deck. If memory serves me correctly the column bent over to the point it had to be replaced.

Acie Chance

-----Original Message-----
From: Mark Deardorff [mailto:mark@rstavares.com]
Sent: Friday, August 24, 2007 1:47 PM
To: seaint@seaint.org
Subject: Guano and Bridge Failure

Here you go. I saw this and thought it was interesting.

http://www.foxnews.com/story/0,2933,294153,00.html

Mark E. Deardorff, SE
R & S Tavares Associates, Inc
9815 Carroll Canyon Road
Suite 206
San Diego, CA 92131
Phone: 858-444-3344
Phone: 209-863-8928
mark@rstavares.com
www.rstavares.com

******* ****** ****** ****** ******* ****** ****** ********

Re: Guano and Bridge Failure

Mark,

I missed this one. It all appears to come to the issue of maintenance. I wonder if any new technical information on that collapse is available.

A couple years ago, I saw some steel bridges in NYC that were in a very bad - to say the least - structural shape. Even Verrazzano did not look that good with rust showing through old paint. I wrote about that on the List trying to get attention of NYC engineers, but did not get any response.

This last May I was in NJ again, and did not find whole lot of changes with the Verrazzano bridge. Other city bridges - on the way to JFK - looked freshly painted, but I was not able to see if the holes (sic) in the girder webs were properly repaired.

Thanks,

V. Steve Gordin, SE
Irvine CA

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

From: Mark Deardorff

To: seaint@seaint.org

Sent: Friday, August 24, 2007 13:46

Subject: Guano and Bridge Failure

Here you go. I saw this and thought it was interesting.

http://www.foxnews.com/story/0,2933,294153,00.html

Mark E. Deardorff, SE
R & S Tavares Associates, Inc
9815 Carroll Canyon Road
Suite 206
San Diego, CA 92131
Phone: 858-444-3344
Phone: 209-863-8928
mark@rstavares.com
www.rstavares.com

******* ****** ******* ******** ******* ******* ******* ***
*   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
******* ****** ****** ****** ******* ****** ****** ********

Guano and Bridge Failure

Here you go. I saw this and thought it was interesting.

http://www.foxnews.com/story/0,2933,294153,00.html

Mark E. Deardorff, SE
R & S Tavares Associates, Inc
9815 Carroll Canyon Road
Suite 206
San Diego, CA 92131
Phone: 858-444-3344
Phone: 209-863-8928
mark@rstavares.com
www.rstavares.com

******* ****** ****** ****** ******* ****** ****** ********

RE: Stud Wind Load

We have a 3 story apartment with 9 foot ceilings in 115 mph Exp B. Using #2 SPF so that we do not have to worry about bowing, etc. The finger jointed studs are not used here much. The Contractor wants to use 2x4's so we are having to dbl them up which is of course causing heartburn. So I figured I would ask to see what others are doing!

-----Original Message-----
From: Josh Comfort [mailto:jcomfort@ggbse.com]
Sent: Friday, August 24, 2007 4:03 PM
To: seaint@seaint.org
Subject: RE: Stud Wind Load

C&C.

What size, spacing and length of studs do you usually see? Also, what sort
of wind region are you in?

For the region I generally design in the worst case is 90 mph, exp C. I
can't recall not being able to get 2x6 @ 16" exterior brg walls to work with
a moderate vertical load and 12' wall height. For taller walls and/or
heavier loads I have gone to 2x8s or 2-2x6, though.

Josh Comfort, P.E.
Golden, Graper & Burton, Inc.
1500 W. Fourth Ave., Suite 509
Spokane, WA 99204
(509)624-3224 (509)624-3225 Fax

-----Original Message-----
From: Zaitz, Michael [mailto:mzaitz@kerncoleman.com]
Sent: Friday, August 24, 2007 12:51 PM
To: seaint@seaint.org
Subject: Stud Wind Load

Interested to hear how others design wood or lt ga wall studs for wind
(multi-family housing). Do you typically use components and cladding or
MWFRS forces? The commentary of ASCE 7-05 indicates that wall studs would
be designed with C&C forces but based on these loads (D+W load combination)
we are getting wall studs much heavier than what I have seen.

Thanks

Mike
This electronic message and any attachments are confidential property of
Kern-Coleman & Co. LLC. The information is intended only for the use of the
person to whom it is addressed. Any other interception, copying, accessing,
or disclosure of this message is prohibited. If you have received this
message in error, please immediately notify Kern-Coleman & Co. Do not
forward this message without permission.

******* ****** ****** ****** ******* ****** ****** ********
This electronic message and any attachments are confidential property of Kern-Coleman & Co. LLC. The information is intended only for the use of the person to whom it is addressed. Any other interception, copying, accessing, or disclosure of this message is prohibited. If you have received this message in error, please immediately notify Kern-Coleman & Co. Do not forward this message without permission.

RE: Stud Wind Load

For transverse wind loads, it should be components and cladding pressures.
If the stud is the end post of a shearwall, then the axial load on the end
post will have a component due to MWFRS pressures as the shearwall would be
part of the MWFRS and thus that overturning/compression post load should be
due to the MWFRS pressure.

Regards,

Scott
Adrian, MI

-----Original Message-----
From: Zaitz, Michael [mailto:mzaitz@kerncoleman.com]
Sent: Friday, August 24, 2007 3:51 PM
To: seaint@seaint.org
Subject: Stud Wind Load

Thanks

******* ****** ****** ****** ******* ****** ****** ********

RE: Stud Wind Load

C&C.

What size, spacing and length of studs do you usually see? Also, what sort
of wind region are you in?

Josh Comfort, P.E.
Golden, Graper & Burton, Inc.
1500 W. Fourth Ave., Suite 509
Spokane, WA 99204
(509)624-3224 (509)624-3225 Fax

-----Original Message-----
From: Zaitz, Michael [mailto:mzaitz@kerncoleman.com]
Sent: Friday, August 24, 2007 12:51 PM
To: seaint@seaint.org
Subject: Stud Wind Load

Thanks

******* ****** ****** ****** ******* ****** ****** ********

Stud Wind Load

Interested to hear how others design wood or lt ga wall studs for wind (multi-family housing). Do you typically use components and cladding or MWFRS forces? The commentary of ASCE 7-05 indicates that wall studs would be designed with C&C forces but based on these loads (D+W load combination) we are getting wall studs much heavier than what I have seen.

Thanks

Mike
This electronic message and any attachments are confidential property of Kern-Coleman & Co. LLC. The information is intended only for the use of the person to whom it is addressed. Any other interception, copying, accessing, or disclosure of this message is prohibited. If you have received this message in error, please immediately notify Kern-Coleman & Co. Do not forward this message without permission.

RE: Job Opportunity - OT

I am currently monitoring this site to see if any of my employees are spending company time.

Just joking, I encourage my employees to participate in this stuff, it is part of their learning experience.

Marlou Rodriguez, S.E.

MBRodriguez Engineering Inc.

2355 Oakland Road, Suite 14

San Jose, CA 95131

Tel: (408) 432-4866

Cel: (408) 761-5013

From: Scott Maxwell [mailto:smaxwell@umich.edu]
Sent: Friday, August 24, 2007 11:42 AM
To: seaint@seaint.org
Subject: RE: Job Opportunity - OT

Me. I don't use company time for SEAINT stuff. As I am part-time and hourly and work from home, I have plenty of spare time to post. Don't know about the others... <grin>

Regards,

Scott

Adrian, MI

-----Original Message-----
From: Donald Bruckman [mailto:bruckmandesign@verizon.net]
Sent: Friday, August 24, 2007 1:49 PM
To: seaint@seaint.org
Subject: RE: Job Opportunity - OT

Who’s paying for all this time spent posting about all this time spent “working” ??

RE: Job Opportunity - OT

Amen…Kudos… Ditto…DO..

Julius

From: Marlou Rodriguez [mailto:mbrodrig@mbrodriguez.com]
Sent: Friday, August 24, 2007 1:50 PM
To: seaint@seaint.org
Subject: RE: Job Opportunity - OT

I am currently monitoring this site to see if any of my employees are spending company time.

Just joking, I encourage my employees to participate in this stuff, it is part of their learning experience.

Marlou Rodriguez, S.E.

MBRodriguez Engineering Inc.

2355 Oakland Road, Suite 14

San Jose, CA 95131

Tel: (408) 432-4866

Cel: (408) 761-5013

From: Scott Maxwell [mailto:smaxwell@umich.edu]
Sent: Friday, August 24, 2007 11:42 AM
To: seaint@seaint.org
Subject: RE: Job Opportunity - OT

Me. I don't use company time for SEAINT stuff. As I am part-time and hourly and work from home, I have plenty of spare time to post. Don't know about the others... <grin>

Regards,

Scott

Adrian, MI

-----Original Message-----
From: Donald Bruckman [mailto:bruckmandesign@verizon.net]
Sent: Friday, August 24, 2007 1:49 PM
To: seaint@seaint.org
Subject: RE: Job Opportunity - OT

Who’s paying for all this time spent posting about all this time spent “working” ??