Saturday, February 2, 2008

Use 8d nails or 10d nails for Structural Panel Shear Walls

I am re-tooling to 2007 CBC wood design. Many items need to be updated.

Many years ago, I was told to stay with 8d and 16d nails (common) as
much as possible. In Doug Thompson's design example 1A, page 19, in
the SDM Vol 2, he uses 10d nails on 4" o.c. with 510 plf allowable
shear. It looks to me that he has been using 10d nails since the 1997
UBC examples. I must be very out of date!

If Simpson Strong-tie's SSN10 nails (shorter than the real 10d) are
used in these applications, the 10d nails make sense. It would be
easier to drive into the studs.

My question is: "Are most of the plywood shear walls are specified
with 10d nails these days in your office standards?"

Thanks

Sam Chang

PS: Seems like a lot information on staples. Are they more commonly
used over the nails in the state of California now?

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Re: NDS 2005 Fe

Bill -
  According to Table 10.3.1 of 2005 NDS, the load duration factor is applied to the controling lateral or withdrawal fastener connection value when determining the adjusted value. It's not applied directly to the fastener's bearing strength.

HTH,
Charlie Canitz,
Annapolis, MD
    


-----Original Message-----
From: Bill Allen <T.W.Allen@cox.net>
To: seaint@seaint.org
Sent: Sat, 2 Feb 2008 10:02 pm
Subject: NDS 2005 Fe

Is Fe itself modified by CD? I'm looking at a table of nail capacities (prepared by someone else) and the author has different values for Fe based on different values of CD.
 
T. William (Bill) Allen, S.E.
Consulting Structural Engineers
 
V (949) 248-8588 F(949) 209-2509

More new features than ever. Check out the new AOL Mail!

NDS 2005 Fe

Is Fe itself modified by CD? I’m looking at a table of nail capacities (prepared by someone else) and the author has different values for Fe based on different values of CD.

 

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

ALLEN DESIGNS

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

Re: Bridges

Rhkratzse@aol.com wrote:
Sure, persuade people (i.e., taxpayers) that nothing's free and if you want your infrastructure to not fall apart you have to pay the taxes necessary for that. 
You're absolutely right. The people simply MUST start paying taxes.

The free ride is OVER.

Friday, February 1, 2008

RE: Steel shop drawings

First this requirement only applys to items that are designed by an engineer other than the structural engineer of record. Typically these are elements that are listed as being defered approval items. This does not apply to steel shop drawings where the design is fully documented on the permit documents.

What we have done is put a special shop drawing like stamp on the drawing and the Structural Engineer wet signs this stamp. The SE stamp never needs to be on these submittals. The stamp or in some instances a stickyback label states that we have reviewed the submittal with regards to the criteria used and how it interfaces with elements of the buildig that we have designed. I don't have the exact magic words handy.

After we afix this stamp to the deferred approval submittal it is then sent to the agency for their review.

DSA and OSHPD know better but they keep trying to get the structural engineer to put his SE stamp on the drawings. There is often a big difference between what they initially say they want and what they will accept.

Mark Gilligan

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RE: ASTM

Deformed bar anchors are not forrmally recognized by the building code. Welding of A706 rebar is not a DBA. Thus formally to use a DBA the building official needs to accept it as an alternate product.

Nelson and another firm have ICC Evaluation Reports which most building departments will accept without question. If you require compliance with one of these evaluation reports you do not need to specify the material or welding process used.

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RE: More wierd Bldg Dept. requests

It is not unheard of for the building department to require submission of changes to the permit documents as they are issued. If you do not get signoff on the modification before it is implemented you and the owner could be sticking your neck out if the building official finds problems at the end of the job. This practice is the norm for hospital and public school projects in California.

You do not have to submit the RFIs that did not result in a change to the permit documents. Some times the way you respond to the RFI can make the difference between a change or clarification.

If you adopt the practice of making the changes on the original CAD files and Xrefing the revised portion of the drawing into a 8.5x11 of 11x17 drawing that is issued with the RFI then you only need submit your sketches or the revised drawings. When I make changes I will submit only the revised sketches and not the RFIs. The building official only needs your revisions and not the RFIs.

With regard signing the shop drawings (and not design-built components), go to the building official and say no. It will not happen. If it is still a problem, after the building department has signoff on the RFI's and other changes to the permit documents, take the position that you have satisfied the requirements of the permit and demand that the certificate of occupancy be issued. The building official really has no option unless he wants to be personally liable for costs to the Owner for delays in opening..

Signing of the steel shop drawings could allow the Contractor to get off the hook if there were differences between the shop drawings and the contract documents.

Mark Gilligan

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RE: ASTM

Jason,
 
Not that you asked, but to add an experience, be aware that there are also minimum straight lengths of DBAs required to work with the welding guns.  If you're working in confinement zones with hooked candy cane bars be careful to give yourself enough room. You need about 10 to 12 inches of straight length before a hook for the gun to be able to grab and weld the bar to steel.
 
I had some confinement bars in the boundary zone of a concrete shear wall built around a steel frame and faced a real challenge getting DBAs with enough straight length to fit into the boundary zone the architect spared me (luckily enough). 
 
-Ben

Harold Sprague <spraguehope@hotmail.com> wrote:
In addition to what Ben stated, you can fillet weld either the A496 or A706, but you will not be able to use the stud gun unless you use the A 496. 
 
The manufactured DBA's have the dimple and come with the appropriate ferrules.  You would have to do a bit of custom machining to use a regular A 706 bar in a stud gun. 

Regards,
Harold Sprague



Date: Fri, 1 Feb 2008 12:44:16 -0800
From: enginerd666@yahoo.com
Subject: Re: ASTM
To: seaint@seaint.org

Jason,
 
A 496 material is the correct designation for the material used by the Nelson arc welding machines.
 
A 706 material would be acceptable for use, in lieu of A 496, if the contractor intended on providing all-around fillet welds to the structural steel (be prepared to give them an appropriate weld thickness schedule, and don't forget the visual inspection).  Fillet welds work up to #6 or somewhere in there before your cross sectional area to circumference ratio makes it impossible to connect with fillet welds.
 
If you're on a small job, contractors sometimes seem to opt for welding the bars themselves rather than bringing in the specialty equipment for the DBAs.
 
A 518?  From what I see this is an iron casting designation.
 
-Ben

Jason Christensen <jason@wcaeng.com> wrote:
Anyone know what the current ASTM designation for DBA (deformed bar anchor) is?
 
I have some shops coming in specifing A496, another set specifing A706 weldable rebar, and another set with A518. 
 
Just wonding what I should be specifing for just a general application?
 
Jason



Benjamin H. Maxwell, S.E.
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Benjamin H. Maxwell, S.E.


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RE: Welding of studs through deck to steel beams

I would suggest:
1.  Size the deck to either be shored or simple span
2.  Size the beams with enough width to accept the deck bearing and enough space for the stud welding.
3.  Lay out stud locations and restrict painting for the studs
4.  Hold the deck away from the stud weld area
5.  Weld the studs directly to the beam, and provide dams for the deck
6.  Field paint the studs and exposed top flange

Regards,
Harold Sprague



Date: Fri, 1 Feb 2008 10:21:25 -0600
From: mhemstad@mbjeng.com
To: seaint@seaint.org
Subject: Welding of studs through deck to steel beams

All,
We have a project using exposed steel beams under acoustic composite metal deck.  This is normal composite metal deck, with a flat perforated sheet of steel spot welded to the bottom of the deck.  Batts of insulation are then stuffed into the resulting cells.  I believe the perforated plate is painted before assemble.
 
When shear studs are then welded through the deck to the beams, they have to pass through two plies of steel.  Two questions arise:
 
AWS D1.1, section 7.4.2, forbids paint on the top flange of the beam.  I am concerned about the possibility of rainwater wicking between the deck and beam, rust blush forming on the beam flange, and then weeping down onto the beam, either requiring re-cleaning before painting or staining the paint after it is applied.  If two layers of metal deck, at least one of which is painted, don't compromise the stud weld, does a coat of shop prime on the beam flange?
 
Second question:  D1.1 section 7.2.7 forbids welding through more than two plies of deck.  Obviously, they will try to butt the deck sections where they can, but I am guessing there will be places where they will want to overlap sections of panel along their edges.  With our acoustic deck, I assume this means that at overlaps they have to cut or punch a hole in the top section of deck.  Since this will be a fight with the contractor, I would appreciate confirmation or thoughts on this.
 
Thanks,
Mike Hemstad
MBJ
Minneapolis, Minnesota
mhemstad@mbjeng.com


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Re: Re-roof on 1950's building

mail wrote:
>
> I have a customer who wants to retrofit a roof system on a school
> building built in the 1950's. The existing construction is concrete
> joists with metal deck, lightweight concrete and a built up flat roof.
> The customer wants to install a wood truss roof system with bearing on
> purlins spaced every few feet on the lightweight concrete deck instead
> of simply replacing the current flat roofing in order to avoid water
> problems and so forth.
>
> What is the proper procedure for addressing a building this old? I
> feel confident that I could design the roof truss system and even the
> anchorage to the existing framing, but what is the extent of my
> responsibility? I am unfamiliar with any existing building codes and
> new to the addition game, so any advice would be appreciated.
>
> Taylor W. Motley, PE
>
> /Strand Engineering, LLC/
>
> /224 Daytona St.// 6/
>
> /Conway//, SC 29526///
>
You would have to verify that the existing roof structure can handle the
additional dead load. Also, the roof/live load may have changed since
the original design and you would have to take that into account. Also,
you would have to check the existing structure for the increased lateral
loads from the additional seismic load (increased roof dead load) and
from the changes that the change in roof profile (increased wind loads).
The IBC allows you a 5% overstress for existing elements, see the
chapter on existing buildings. Also, you could look the International
Existing Building Code, they may have some sections that may help you. I
have only used this publication when dealing with minor alterations on
unreinforced masonry.

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RE: ASTM

In addition to what Ben stated, you can fillet weld either the A496 or A706, but you will not be able to use the stud gun unless you use the A 496. 
 
The manufactured DBA's have the dimple and come with the appropriate ferrules.  You would have to do a bit of custom machining to use a regular A 706 bar in a stud gun. 

Regards,
Harold Sprague



Date: Fri, 1 Feb 2008 12:44:16 -0800
From: enginerd666@yahoo.com
Subject: Re: ASTM
To: seaint@seaint.org

Jason,
 
A 496 material is the correct designation for the material used by the Nelson arc welding machines.
 
A 706 material would be acceptable for use, in lieu of A 496, if the contractor intended on providing all-around fillet welds to the structural steel (be prepared to give them an appropriate weld thickness schedule, and don't forget the visual inspection).  Fillet welds work up to #6 or somewhere in there before your cross sectional area to circumference ratio makes it impossible to connect with fillet welds.
 
If you're on a small job, contractors sometimes seem to opt for welding the bars themselves rather than bringing in the specialty equipment for the DBAs.
 
A 518?  From what I see this is an iron casting designation.
 
-Ben

Jason Christensen <jason@wcaeng.com> wrote:
Anyone know what the current ASTM designation for DBA (deformed bar anchor) is?
 
I have some shops coming in specifing A496, another set specifing A706 weldable rebar, and another set with A518. 
 
Just wonding what I should be specifing for just a general application?
 
Jason



Benjamin H. Maxwell, S.E.
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Re: Stainless Steel Washers...

Hey Christopher,
 
Thanks for the reply.  I'll have to follow up with Hilti about the use of A 240 material as a stainless steel washer.  Certainly the use of a washer for a concrete anchor is different than use in a structural steel connection.
 
I found in ASTM F 1077 "Standard Guide for Selection of Committee F16 Fastener Specifications" that there are no ASTM designations that cover stainless steel washers.  There are designations for SS bolts, nuts, hex cap screws, socket head screws, socket button and flat screws, and studs.  Just don't ask for stainless washers.
 
I guess that leaves one with using F 436 Type 3 washers.
 
-Ben

Christopher Wright <chrisw@skypoint.com> wrote:

On Jan 29, 2008, at 6:46 PM, Benjamin Maxwell wrote:

> The best approach I've seen is specifying stainless steel plate
> material ASTM A 240 AISI types 304 or 316 - depending on your
> application, with the washer dimensions conforming to ANSI B18.22.1
> Type A Plain. This was taken from the Hilti Product Technical
> Manual. Simpson and Powers have similar stuff, but not as detailed.
A-240 plate is supplied annealed--probably too soft for a washer
unless you're using it for something besides a washer. F-436 may have
more on washers for use with stainless fasteners.
>

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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Benjamin H. Maxwell, S.E.


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re-roof 1950's building

Hi:

 

Is the owner’s objective to get more slope on the roof?

 

If so, you may want to consider using new tapered rigid foam insulation over the lightweight concrete deck, then place roofing over the foam.  It will change the slope by the amount you specify.  It is not cheap, but there are several products which are computer cut for the slope you specify.  Another advantage is increased energy insulation.

 

An advantage with this alternative is there is no significant additional structural loads to the existing structure.  You may consider doing a calculation of the existing members.

 

If I understand your e-mail, however, for the system you are describing, I believe the Code requires a complete seismic analysis and possible seismic strengthening of the building.  Logically, in an earthquake, the new roof structure you are describing can take the earthquake diaphragm loads, transfer them to the existing walls, and then into the footings.  But, what about the existing steel structure?  It may collapse, leaving the new wood roof structure in tact.  Wood is much more flexible than steel deck with light-weight concrete fill.  The steel with fill would probably be significantly more rigid and try to take the entire earthquake diaphragm load till failure, then the load would be transferred to the wood diaphragm.  By then it may be too late.

 

With Joy and Hope,

Bob Freeman, AIA, EIT

IDS Group, Inc.

(949) 387-8500

RE: ASTM

Thanks,

 

Your comments were what I was thinking, except I had never seen the A518.

 

Jason

 

 

-----Original Message-----
From: Benjamin Maxwell [mailto:enginerd666@yahoo.com]
Sent: Friday, February 01, 2008 1:44 PM
To: seaint@seaint.org
Subject: Re: ASTM

 

Jason,

 

A 496 material is the correct designation for the material used by the Nelson arc welding machines.

 

A 706 material would be acceptable for use, in lieu of A 496, if the contractor intended on providing all-around fillet welds to the structural steel (be prepared to give them an appropriate weld thickness schedule, and don't forget the visual inspection).  Fillet welds work up to #6 or somewhere in there before your cross sectional area to circumference ratio makes it impossible to connect with fillet welds.

 

If you're on a small job, contractors sometimes seem to opt for welding the bars themselves rather than bringing in the specialty equipment for the DBAs.

 

A 518?  From what I see this is an iron casting designation.

 

-Ben

Jason Christensen <jason@wcaeng.com> wrote:

Anyone know what the current ASTM designation for DBA (deformed bar anchor) is?

 

I have some shops coming in specifing A496, another set specifing A706 weldable rebar, and another set with A518. 

 

Just wonding what I should be specifing for just a general application?

 

Jason




Benjamin H. Maxwell, S.E.

 


Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now.

Re: ASTM

Jason,
 
A 496 material is the correct designation for the material used by the Nelson arc welding machines.
 
A 706 material would be acceptable for use, in lieu of A 496, if the contractor intended on providing all-around fillet welds to the structural steel (be prepared to give them an appropriate weld thickness schedule, and don't forget the visual inspection).  Fillet welds work up to #6 or somewhere in there before your cross sectional area to circumference ratio makes it impossible to connect with fillet welds.
 
If you're on a small job, contractors sometimes seem to opt for welding the bars themselves rather than bringing in the specialty equipment for the DBAs.
 
A 518?  From what I see this is an iron casting designation.
 
-Ben

Jason Christensen <jason@wcaeng.com> wrote:
Anyone know what the current ASTM designation for DBA (deformed bar anchor) is?
 
I have some shops coming in specifing A496, another set specifing A706 weldable rebar, and another set with A518. 
 
Just wonding what I should be specifing for just a general application?
 
Jason



Benjamin H. Maxwell, S.E.


Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now.

RE: Re-roof on 1950's building

The existing gravel and built-up roof will be removed all the way down to the light weight concrete deck. The original roof framing will remain intact though. In any case the additional weight of the wood framing would probably not exceed the current weight of the gravel and membrane roof system it will be replacing.

 


From: Gerard Madden, SE [mailto:gmse4603@gmail.com]
Sent: Friday, February 01, 2008 3:04 PM
To: seaint@seaint.org
Subject: Re: Re-roof on 1950's building

 

Your gravity loads would be going up if I'm understanding correctly. You are "overlaying" a secondary roof without removing the original roof system and roof framing...



-gm

On Feb 1, 2008 11:56 AM, mail <mail@strand-engineering.com> wrote:

This would be going over the top of existing construction. Bigger question to me is am I assuming liability for the entire structure by re-designing the roof system (gravity loads are less, but lateral would increase a little), in which case I would need to analyze everything existing? Or am I only responsible for the portion that I design?

 


From: Gerard Madden, SE [mailto:gmse4603@gmail.com]
Sent: Friday, February 01, 2008 2:51 PM
To: seaint@seaint.org
Subject: Re: Re-roof on 1950's building

 

First thing to check is to see if it's okay to introduce a combustible material into the buidling.

or are you trying to go over the top of the existing contruction? (i.e. above the existing conc. filled deck) to somehow keep the structure weathertight during construction?

-gm

On Feb 1, 2008 11:19 AM, mail <mail@strand-engineering.com> wrote:

I have a customer who wants to retrofit a roof system on a school building built in the 1950's. The existing construction is concrete joists with metal deck, lightweight concrete and a built up flat roof. The customer wants to install a wood truss roof system with bearing on purlins spaced every few feet on the lightweight concrete deck instead of simply replacing the current flat roofing in order to avoid water problems and so forth.

 

What is the proper procedure for addressing a building this old? I feel confident that I could design the roof truss system and even the anchorage to the existing framing, but what is the extent of my responsibility? I am unfamiliar with any existing building codes and new to the addition game, so any advice would be appreciated.

 

Taylor W. Motley, PE

Strand Engineering, LLC

224 Daytona St. 6

Conway, SC 29526

 

 

 




--
-gm




--
-gm

Re: Re-roof on 1950's building

Your gravity loads would be going up if I'm understanding correctly. You are "overlaying" a secondary roof without removing the original roof system and roof framing...



-gm

On Feb 1, 2008 11:56 AM, mail <mail@strand-engineering.com> wrote:

This would be going over the top of existing construction. Bigger question to me is am I assuming liability for the entire structure by re-designing the roof system (gravity loads are less, but lateral would increase a little), in which case I would need to analyze everything existing? Or am I only responsible for the portion that I design?

 


From: Gerard Madden, SE [mailto:gmse4603@gmail.com]
Sent: Friday, February 01, 2008 2:51 PM
To: seaint@seaint.org
Subject: Re: Re-roof on 1950's building

 

First thing to check is to see if it's okay to introduce a combustible material into the buidling.

or are you trying to go over the top of the existing contruction? (i.e. above the existing conc. filled deck) to somehow keep the structure weathertight during construction?

-gm

On Feb 1, 2008 11:19 AM, mail <mail@strand-engineering.com> wrote:

I have a customer who wants to retrofit a roof system on a school building built in the 1950's. The existing construction is concrete joists with metal deck, lightweight concrete and a built up flat roof. The customer wants to install a wood truss roof system with bearing on purlins spaced every few feet on the lightweight concrete deck instead of simply replacing the current flat roofing in order to avoid water problems and so forth.

 

What is the proper procedure for addressing a building this old? I feel confident that I could design the roof truss system and even the anchorage to the existing framing, but what is the extent of my responsibility? I am unfamiliar with any existing building codes and new to the addition game, so any advice would be appreciated.

 

Taylor W. Motley, PE

Strand Engineering, LLC

224 Daytona St. 6

Conway, SC 29526

 

 

 




--
-gm




--
-gm

RE: Re-roof on 1950's building

This would be going over the top of existing construction. Bigger question to me is am I assuming liability for the entire structure by re-designing the roof system (gravity loads are less, but lateral would increase a little), in which case I would need to analyze everything existing? Or am I only responsible for the portion that I design?

 


From: Gerard Madden, SE [mailto:gmse4603@gmail.com]
Sent: Friday, February 01, 2008 2:51 PM
To: seaint@seaint.org
Subject: Re: Re-roof on 1950's building

 

First thing to check is to see if it's okay to introduce a combustible material into the buidling.

or are you trying to go over the top of the existing contruction? (i.e. above the existing conc. filled deck) to somehow keep the structure weathertight during construction?

-gm

On Feb 1, 2008 11:19 AM, mail <mail@strand-engineering.com> wrote:

I have a customer who wants to retrofit a roof system on a school building built in the 1950's. The existing construction is concrete joists with metal deck, lightweight concrete and a built up flat roof. The customer wants to install a wood truss roof system with bearing on purlins spaced every few feet on the lightweight concrete deck instead of simply replacing the current flat roofing in order to avoid water problems and so forth.

 

What is the proper procedure for addressing a building this old? I feel confident that I could design the roof truss system and even the anchorage to the existing framing, but what is the extent of my responsibility? I am unfamiliar with any existing building codes and new to the addition game, so any advice would be appreciated.

 

Taylor W. Motley, PE

Strand Engineering, LLC

224 Daytona St. 6

Conway, SC 29526

 

 

 




--
-gm

Re: Re-roof on 1950's building

First thing to check is to see if it's okay to introduce a combustible material into the buidling.

or are you trying to go over the top of the existing contruction? (i.e. above the existing conc. filled deck) to somehow keep the structure weathertight during construction?

-gm

On Feb 1, 2008 11:19 AM, mail <mail@strand-engineering.com> wrote:

I have a customer who wants to retrofit a roof system on a school building built in the 1950's. The existing construction is concrete joists with metal deck, lightweight concrete and a built up flat roof. The customer wants to install a wood truss roof system with bearing on purlins spaced every few feet on the lightweight concrete deck instead of simply replacing the current flat roofing in order to avoid water problems and so forth.

 

What is the proper procedure for addressing a building this old? I feel confident that I could design the roof truss system and even the anchorage to the existing framing, but what is the extent of my responsibility? I am unfamiliar with any existing building codes and new to the addition game, so any advice would be appreciated.

 

Taylor W. Motley, PE

Strand Engineering, LLC

224 Daytona St. 6

Conway, SC 29526

 

 

 




--
-gm

Re-roof on 1950's building

I have a customer who wants to retrofit a roof system on a school building built in the 1950’s. The existing construction is concrete joists with metal deck, lightweight concrete and a built up flat roof. The customer wants to install a wood truss roof system with bearing on purlins spaced every few feet on the lightweight concrete deck instead of simply replacing the current flat roofing in order to avoid water problems and so forth.

 

What is the proper procedure for addressing a building this old? I feel confident that I could design the roof truss system and even the anchorage to the existing framing, but what is the extent of my responsibility? I am unfamiliar with any existing building codes and new to the addition game, so any advice would be appreciated.

 

Taylor W. Motley, PE

Strand Engineering, LLC

224 Daytona St. 6

Conway, SC 29526

 

 

 

Re: Welding of studs through deck to steel beams

Mike,



I was a field engineer on a job where ordinary composite
floor deck was lapped on top of steel beams.
Studs were than welded through the two layers of deck onto the top
flange. A lot of the welds didn't work
because water from rain and dew had wicked between the two layers of deck and
between the deck and the beam. Also, the
operator didn't adjust the power on his welder properly. I think the beams were primed but can't
remember for sure.



It was educational to walk on the deck beside a row of studs
and tap each one with a light sledge hammer.
The good ones gave of a "ping" and the bad ones gave off a
"klunk" and fell over. I will
do this on all my jobs where I have the opportunity and would make that suggestion
to you.



hth


MJ

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Re: Crane rail weld/assembly papers

On Feb 1, 2008, at 9:48 AM, Harold Sprague wrote:

> In addition to what has been offered, you should reference the
> "Whiting Crane Handbook". You can get the third edition on this
> web site:
>
> http://www.slideruleera.net/miscellaneous.html

tanks for the link. This is a primo page. The Whiting Crane Handbook
is a gem.

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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ASTM

Anyone know what the current ASTM designation for DBA (deformed bar anchor) is?

 

I have some shops coming in specifing A496, another set specifing A706 weldable rebar, and another set with A518. 

 

Just wonding what I should be specifing for just a general application?

 

Jason

RE: Steel shop drawings

Right.

 

To be clear, Bob, this is really not much more than a shop drawing stamp with the addition of the S.E. seal, correct? I know when this procedure was developed quite a while back, DSA (that term dates me right off the bat) was sensitive to the concerns we had about stamping and signing shop drawings.

 

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

ALLEN DESIGNS

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

-----Original Message-----
From: Bob Freeman [mailto:robert.freeman@idsse.com]
Sent: Friday, February 01, 2008 8:44 AM
To:
seaint@seaint.org
Subject: Steel shop drawings

 

Hi Mr. Bruckman:

 

Only on School and Hospital projects are we required to ‘stamp and sign’ shop drawings.

 

We print our information about reviewing according to calcs and drawings on a label with the engineering seal, and sign the label, and stick it on the shop drawings.

 

With Joy and Hope,

Bob Freeman, AIA, EIT

IDS Group, Inc.

(949) 387-8500

RE: More wierd Bldg Dept. requests

I get asked to do this all the time but I never do. The best I can provide
is a shop drawing stamp stating "no exceptions taken". There is nothing more
I can do from a legal, moral or insurable point of view.

It sounds like the inspector is attempting to divert his share of
responsibility.

T. William (Bill) Allen, S.E.
ALLEN DESIGNS
Consulting Structural Engineers

> -----Original Message-----
> From: bruckmandesign@verizon.net [mailto:bruckmandesign@verizon.net]
> Sent: Friday, February 01, 2008 8:23 AM
> To: seaint@seaint.org
> Subject: More wierd Bldg Dept. requests
>
> I'm finishing up a big box construction up in NoCal, and as we go through
> final inspections, the inspector asks for a closeout set of all the wet
> stamped RFI clarification details that had been sent by the SE to the job.
> Okay...I get that. The RFI responses, technically altered the permit docs
> and should, I guess, be part of the record.
>
> But, here's the stunner, at least to me: He then says he wants the SE to
> also wet stamp and seal the structural steel shop drawings!!
>
> I say to him, "...you mean, wet stamp with that catch-all, 'I reviewed
> 'em, but take no responsibility for anything I saw' stamp?"
> "No", he says, "I want a full set of shop drawings wet-stamped SEALED AND
> SIGNED by your engineer."
>
> Now, first off, I'm not even sure it's legal to do that, since the shop
> drawings were not prepared by the SE; second, speaking with my architect's
> hat on, no way I'd do such a thing short of there being severe furnace
> problems in the underworld.
>
> I'll let you all know what the SE says when I break it to him today, but
> in the meantime....
>
> Anyone had to do this?
>
> -db
>
>
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Steel shop drawings

Hi Mr. Bruckman:

 

Only on School and Hospital projects are we required to ‘stamp and sign’ shop drawings.

 

We print our information about reviewing according to calcs and drawings on a label with the engineering seal, and sign the label, and stick it on the shop drawings.

 

With Joy and Hope,

Bob Freeman, AIA, EIT

IDS Group, Inc.

(949) 387-8500

Re: More wierd Bldg Dept. requests

Wow.  was there a lot of field issues that could have ruffles the feathers of said inspector?  I would go to the BO first.  Good luck.

On Feb 1, 2008 8:22 AM, <bruckmandesign@verizon.net> wrote:
I'm finishing up a big box construction up in NoCal, and as we go through final inspections, the inspector asks for a closeout set of all the wet stamped RFI clarification details that had been sent by the SE to the job.  Okay...I get that.  The RFI responses, technically altered the permit docs and should, I guess, be part of the record.

But, here's the stunner, at least to me:  He then says he wants the SE to also wet stamp and seal the structural steel shop drawings!!

I say to him, "...you mean, wet stamp with that catch-all, 'I reviewed 'em, but take no responsibility for anything I saw' stamp?"
"No", he says, "I want a full set of shop drawings wet-stamped SEALED AND SIGNED by your engineer."

Now, first off, I'm not even sure it's legal to do that, since the shop drawings were not prepared by the SE; second, speaking with my architect's hat on, no way I'd do such a thing short of there being severe furnace problems in the underworld.

I'll let you all know what the SE says when I break it to him today, but in the meantime....

Anyone had to do this?

-db


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--
David Topete, SE

RE: More wierd Bldg Dept. requests

Don:

Not sure about Calif., but in the Great State of Illinois, this is violation
of the
"Structural Engineering Act" which says that unless the SEOR (paraphrasing
here)
"Performs separate calculations and analysis sufficient to satisfy himself
that the design complies with all applicable codes" he cannot seal drawings
prepared by others.

Why on earth he would do that with shop drawings in the first place and take
on that liability, that's another matter.


His O and E carrier will go into the fetal position when he gets wind of
this.


No, if the shops are to be sealed (a spec requirement or larger projects
commonly), it must be by the steel fab's SE; not by the SEOR.

We get asked to provide sealed dwgs and calcs for precast components by the
City of Chicago, but they require that it be done by the PC's SE.


Actually, one time, when we were in a crunch, I actually (don't know why)
offered to seal the drawings of the precaster (VERY small project, after
doing the necessary checks, of course), but the City REFUSED to let us do
this.

Cheers,


David L. Fisher SE PE
Senior Director

The Fisher Companies Ltd. - Cayman
372 West Ontario Chicago 60610
75 Fort Street Georgetown Grand Cayman BWI
319 A Street Boston 02210


312.573.1701
312.573.1726 facsimile
312.622.0409 mobile

www.ccgch.com
www.fpse.com

-----Original Message-----
From: bruckmandesign@verizon.net [mailto:bruckmandesign@verizon.net]
Sent: Friday, February 01, 2008 10:23 AM
To: seaint@seaint.org
Subject: More wierd Bldg Dept. requests

I'm finishing up a big box construction up in NoCal, and as we go through
final inspections, the inspector asks for a closeout set of all the wet
stamped RFI clarification details that had been sent by the SE to the job.
Okay...I get that. The RFI responses, technically altered the permit docs
and should, I guess, be part of the record.

But, here's the stunner, at least to me: He then says he wants the SE to
also wet stamp and seal the structural steel shop drawings!!

I say to him, "...you mean, wet stamp with that catch-all, 'I reviewed 'em,
but take no responsibility for anything I saw' stamp?"
"No", he says, "I want a full set of shop drawings wet-stamped SEALED AND
SIGNED by your engineer."

Now, first off, I'm not even sure it's legal to do that, since the shop
drawings were not prepared by the SE; second, speaking with my architect's
hat on, no way I'd do such a thing short of there being severe furnace
problems in the underworld.

I'll let you all know what the SE says when I break it to him today, but in
the meantime....

Anyone had to do this?

-db


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More wierd Bldg Dept. requests

I'm finishing up a big box construction up in NoCal, and as we go through final inspections, the inspector asks for a closeout set of all the wet stamped RFI clarification details that had been sent by the SE to the job. Okay...I get that. The RFI responses, technically altered the permit docs and should, I guess, be part of the record.

But, here's the stunner, at least to me: He then says he wants the SE to also wet stamp and seal the structural steel shop drawings!!

I say to him, "...you mean, wet stamp with that catch-all, 'I reviewed 'em, but take no responsibility for anything I saw' stamp?"
"No", he says, "I want a full set of shop drawings wet-stamped SEALED AND SIGNED by your engineer."

Now, first off, I'm not even sure it's legal to do that, since the shop drawings were not prepared by the SE; second, speaking with my architect's hat on, no way I'd do such a thing short of there being severe furnace problems in the underworld.

I'll let you all know what the SE says when I break it to him today, but in the meantime....

Anyone had to do this?

-db


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Welding of studs through deck to steel beams

All,
We have a project using exposed steel beams under acoustic composite metal deck.  This is normal composite metal deck, with a flat perforated sheet of steel spot welded to the bottom of the deck.  Batts of insulation are then stuffed into the resulting cells.  I believe the perforated plate is painted before assemble.
 
When shear studs are then welded through the deck to the beams, they have to pass through two plies of steel.  Two questions arise:
 
AWS D1.1, section 7.4.2, forbids paint on the top flange of the beam.  I am concerned about the possibility of rainwater wicking between the deck and beam, rust blush forming on the beam flange, and then weeping down onto the beam, either requiring re-cleaning before painting or staining the paint after it is applied.  If two layers of metal deck, at least one of which is painted, don't compromise the stud weld, does a coat of shop prime on the beam flange?
 
Second question:  D1.1 section 7.2.7 forbids welding through more than two plies of deck.  Obviously, they will try to butt the deck sections where they can, but I am guessing there will be places where they will want to overlap sections of panel along their edges.  With our acoustic deck, I assume this means that at overlaps they have to cut or punch a hole in the top section of deck.  Since this will be a fight with the contractor, I would appreciate confirmation or thoughts on this.
 
Thanks,
Mike Hemstad
MBJ
Minneapolis, Minnesota
mhemstad@mbjeng.com

Re: Crane rail weld/assembly papers

Thanks for all the replies. ADG 7 was what I was remembering. I'll also
check out the other references.

Jordan

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RE: Crane rail weld/assembly papers

Jordan,
In addition to what has been offered, you should reference the "Whiting Crane Handbook".  You can get the third edition on this web site:

http://www.slideruleera.net/miscellaneous.html

Regards,
Harold Sprague



To: seaint@seaint.org
Subject: Re: Crane rail weld/assembly papers
From: Tom.Hunt@fluor.com
Date: Thu, 31 Jan 2008 12:38:53 -0800


Jordan,

If are looking for requirements of the rail then you should first look at CMAA #70.  For other reference material (and they are free) would be CISC, Crane-Supporting Steel Structures, and UFC 3-320-07N, Weight Handling Equipment.  AISCs closet design guide might be Steel Design Guide Series 7, Industrial Buildings.  If you search AISC Journal you will also find lots of good articles.

Thomas Hunt, S.E.
Fluor



"Jordan Truesdell, PE" <seaint2@truesdellengineering.com>
01/31/2008 12:14 PM
Please respond to seaint
To
seaint@seaint.org
cc
Subject
Crane rail weld/assembly papers





I thought that there was an AISC design guide on crane rails, but just
looked and it wasn't in my binder.  I seem to remember something from
AISC on crane rails, but can't remember where I saw it. Can someone help
jog my memory?

Any other papers on weld failures for crane rails would be helpful, if
you know of them.  The instance I'm looking at is a crack at the
channel-W interface where there was tight spacing for the weld. I
haven't inspected it, so I can't really expand on details. It's been
several years since I've done a crane rail and I'd like to shake off the
rust before I go take a look at it in person.

--
Jordan


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