Structural Engineering

mailto:sch.tectonic@bigpond.com

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

-----Original Message-----
From: Daryl Richardson [mailto:h.d.richardson@shaw.ca]
Sent: Friday, December 05, 2008 8:43 AM
To: seaint@seaint.org
Subject: Re: Cost Effective Mechanical Lap Splice?

Fellow engineers,

Sorry to be butting into this discussion at such a late date; but why don't you just weld on an extension to the rebar to increase the length of the lap? Logic (at least to me) suggests that the force in the bars will be decreasing from the pour break to the end of the bar, therefore, the weld will be in a location of low force; and, therefore, even a poor quality weld (or slightly heat deteriorated rebar as a result of the weld) should be more than adequate.

Just a thought.

Regards,

H. Daryl Richardson

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

From: Bill Allen

To: seaint@seaint.org

Sent: Thursday, December 04, 2008 7:24 PM

Subject: RE: Cost Effective Mechanical Lap Splice?

If the contractor uses 7,000 psi concrete to get the required lap length short enough, can he go back to 5,000 psi concrete beyond the lap splice?

I can't see any reason why not, but I could be missing something.

TIA,

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

ALLEN DESIGNS

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

re: lap splices

Conrad,

From a numbers/equation standpoint, the formula in ACI for lap splice length is roughly (without getting into all the nitty gritty factors and conditions):

Bar yield stress * diam bar * other factors (coated bars/ normal wt concrete)

(25 or 20)* sq rt of compressive strength of concrete

So increasing the concrete strength decreases your required lap strength, albeit in an “inverse square” relationship so it is of a diminishing return. I think I said that properly.

From a mechanics background perspective, it is related to the splitting strength of concrete, which is related to tensile strength, which is approximately 10-15% of the compressive strength . From what I understand before the 1970s there were flexural bond and anchorage bond requirements. But that did not properly address issues with splitting, specifically in situations where bars had little cover.

This makes for some pretty good bedtime reading if you are tossing and turning, ACI R12.1 Commentary…. There are three solid pages in ACI dedicated just to tension lap splices, but for most everyday situations you can boil the lap splices down to some very basic lengths. Most offices have a note on their dwgs that cover these situations. There are many others on this list who are more qualified to speak on this subject but that is a quick and dirty version.

Andrew Kester, PE

Orlando, FL

Re: Cost Effective Mechanical Lap Splice?

Fellow engineers,

Just a thought.

Regards,

H. Daryl Richardson

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

From: Bill Allen

To: seaint@seaint.org

Sent: Thursday, December 04, 2008 7:24 PM

Subject: RE: Cost Effective Mechanical Lap Splice?

If the contractor uses 7,000 psi concrete to get the required lap length short enough, can he go back to 5,000 psi concrete beyond the lap splice?

I can't see any reason why not, but I could be missing something.

TIA,

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

ALLEN DESIGNS

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

RE: Deletion of ASTM F1642 Airblast Testing from USGS Specs

David,
This is a timely question. The UFGS revision was kind of an interim. There is a more well crafted revision in the works. There has been no small amount of confusion with this. Some Corps districts (like Louisville) have developed their own specification which has enhanced the ambiguity.

I am getting a schedule of the next sanctioned revision of the specification and I will post it. Keep in mind that the UFGS is a guide specification. If you want to offer the airblast test per ASTM F1642, that is your call as the designer. If you do, I would encourage you to add more guidance about the airblast test if you feel it to be appropriate. They are supposed to be clear in the connection requirements. If the submittal is in doubt, whomever is doing the compliance determination should reject it.

Regards, Harold Sprague

Subject: Deletion of ASTM F1642 Airblast Testing from USGS Specs
Date: Thu, 4 Dec 2008 10:16:35 -0500
From: David.Dickey@masonandhanger.com
To: seaint@seaint.org

The option to use Airblast test results per ASTM F1642 to verify a window's adequacy for meeting UFC 4-010-01 antiterrorism requirements has been deleted from the latest versions of USGS window guide specifications. The only option now is to perform a design analysis with calculations. Why has the airblast paragraph been deleted?

There were many problems associated with using the airblast tests to approve a window system. For example, the size of the tested window had to be within +10%/-25% of the window size used on the project, or additional testing was required. The tested charge weight and standoff rarely matched project requirements. The pressure may have met the spec but impulse did not. Often the test results were not clear as to what type of connections to the supporting structure and their spacings were used. Clearing effects occur around a test apparatus that do not occur on a window installed in an actual building wall.

Were any of these problems the reason that the airblast option was eliminated, or is there a different reason?

Thanks,

David Dickey, PE

Lexington, KY

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RE: Moment Resisting Frame

Mondo,
Apparently you are referencing an older code. The use of Rw and the term seismic "zones" has been discontinued for quite some time.

That said, if you are in a region of low seismic risk as set forth in ACI 318-05 Section 21.2.1.2, you do not need to design for the seismic provisions of Chapter 21. But you may have some detailing to which you need to comply which is listed in Section 21.2.1.2.

Regards, Harold Sprague

Date: Thu, 4 Dec 2008 19:40:33 -0800
From: engr_mondo@yahoo.com
Subject: Moment Resisting Frame
To: seaint@seaint.org

All,

Regards,

Mondo

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Thursday, December 4, 2008

RE: Cost Effective Mechanical Lap Splice?

Thanks Dave,

I was leaning more towards what mechanism, causes such relationship? My
assumption being the bond the cement can provide is constant, and the
primary contributor to compressive strength of the concrete is the
aggregate. Therefore what is happening at the interface between the steel
and concrete to provide increased bond?

My further assumption being that if have an answer to that question, then
Bill has answer to where he can cut off the use of the higher strength
concrete and move back to normal strength: barring some code clause which
may otherwise prevent doing so.

And the practicality of mixing two grades of concrete in the new part of the
construction. How large is the retaining wall? How many pours? I assume
changing grades with the wet mix, is not a good idea, when the pour is
vertical, and the two can mix?

Not with holding, I don't understand reinforced concrete.

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

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Moment Resisting Frame

All,

Regards,

Mondo

RE: Cost Effective Mechanical Lap Splice?

Conrad,

Splice or lap length is a function of concrete strength. Increasing the concrete strength to 7000 psi must have given him enough lap length for the dowels, as installed.

Dave Gaines, P.E.

Structural Project Engineer
HDR ONE COMPANY | Many Solutions
251 S. Lake Ave, Suite 1000
Pasadena, CA 91101
T: 626.584.4960
F: 626.584.1750
email: david.gaines@hdrinc.com

From: Conrad Harrison [mailto:sch.tectonic@bigpond.com]
Sent: Thursday, December 04, 2008 6:43 PM
To: seaint@seaint.org
Subject: RE: Cost Effective Mechanical Lap Splice?

Bill,

Concrete is not my thing. But curious, why or how does increasing the compressive strength of concrete increase the strength of bond between steel and concrete? Assuming that is what lap length is about.

Regards

Conrad Harrison

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

Adelaide

South Australia

From: Bill Allen [mailto:t.w.allen@cox.net]
Sent: Friday, 5 December 2008 12:54
To: seaint@seaint.org
Subject: RE: Cost Effective Mechanical Lap Splice?

If the contractor uses 7,000 psi concrete to get the required lap length short enough, can he go back to 5,000 psi concrete beyond the lap splice?

I can't see any reason why not, but I could be missing something.

TIA,

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

mailto:sch.tectonic@bigpond.com

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

RE: Cost Effective Mechanical Lap Splice?

Bill,

Regards

Conrad Harrison

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

Adelaide

South Australia

From: Bill Allen [mailto:t.w.allen@cox.net]
Sent: Friday, 5 December 2008 12:54
To: seaint@seaint.org
Subject: RE: Cost Effective Mechanical Lap Splice?

If the contractor uses 7,000 psi concrete to get the required lap length short enough, can he go back to 5,000 psi concrete beyond the lap splice?

I can't see any reason why not, but I could be missing something.

TIA,

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

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

RE: Wind load on sloped roof with parapet

Jeff,

And from clause 6.5.12.2.4 you are given the net pressure coefficient. Seems
you have it easy.

In which case only apply wall pressure up to bottom of parapet, and the
parapet pressure for the height of the parapet.

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

RE: Cost Effective Mechanical Lap Splice?

If the contractor uses 7,000 psi concrete to get the required lap length short enough, can he go back to 5,000 psi concrete beyond the lap splice?

I can't see any reason why not, but I could be missing something.

TIA,

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

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

RE: Wind load on sloped roof with parapet

Jeff,

From a brief glance at ASCE07-05, B & D zones, appear to be the horizontal
pressures on the sloping roof surface, and may well be close to zero (though
not sure -- represents zero for interpolation purposes). Whilst A & C are
the wall pressures. I would assume the parapet is an extension of the wall
and apply the wall pressures the full height, from ground level to top of
parapet.

Irrespective of transverse or longitudinal directions the typical
distribution is:

Positive pressure to windward wall, suction to leeward wall, with side walls
experiencing suction which is highest at the windward edge and diminishes
(magnitude) towards the leeward edge. The roof pressure likewise experiences
suction which is typically highest at the wind ward edge and diminishes
towards the leeward edge. Depending on the roof pitch, for the transverse
direction, the windward face may become positive, with the leeward face
remaining with suction.

For whole building stability the appropriate pressures should be applied to
all surfaces at the same time. If designing a framed structure rather than
diaphragm box then can apply conservative pressure coefficients to
individual elements, and design in relative isolation. For example design
the parapet as a cantilever above the roof.

The parapet has a windward face, and a leeward face, and doesn't really have
a top or side faces. The windward face has the windward wall pressure, and
the leeward face has the roof pressure coefficient. That is the pressure
coefficient normal to the roof surface is experienced normal to the parapet
wall surface: not horizontal components there off. It is fluid pressure,
experienced at a surface. Typically pressure towards one face, and away from
the other: therefore net pressure sum of absolute magnitudes. (Transversely)

Longitudinally, the parapet experiences suction as a sidewall, and suction
on roof side face from roof surface. To pressures away from each other,
therefore net lower, therefore not critical condition.

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

RE: Wind load on sloped roof with parapet

I am traveling, away from the office, but to clarify Harolds response, the wind design example I was refering to was a wind example at the end of the seismic design manual.

Going from memory, if you interpolate 22.5 degree roof at 85 mph, I was reading that B and D were either negative or close to zero?

Thanks,

Jeff

-------------- Original message --------------
From: Harold Sprague <spraguehope@hotmail.com>
I guess I am missing something, but I do not see how B and D can be zero. You could conservatively assume the parapet loading and apply it to the combined effects.

I don't have a copy of the 2006 IBC Seismic Design Manual, but there are no zones any longer. There are Seismic Design Categories to which I believe you are referencing. Look at ASCE Section 11.1.2 for the scope for the exemptions.

Regards, Harold Sprague

From: jeffsmith7@comcast.net
To: seaint@seaint.org
Subject: RE: Wind load on sloped roof with parapet
Date: Mon, 1 Dec 2008 14:14:56 -0800

Thanks, Harold and Conrad,

I am a bit embarrassed not to know this, I have not done an ASCE 7-05 wind analysis for a building yet.

For this building the B and D zones are zero. So do I take the pressure on the parapet from 6.5.12.4.1 and add that to zones A and C to get the force for the MWFRS in the transverse direction or would I take the A and C zones to the top of the parapet for the MWFRS and design the parapet separately per 6.5.12.4.1?

On another note, The 2006 IBC seismic design manual on page 202 only takes the minimum 10 psf check up to zones A & C, is that correct?

Jeff

From: Harold Sprague [mailto:spraguehope@hotmail.com]
Sent: Monday, December 01, 2008 8:22 AM
To: seaint@seaint.org
Subject: RE: Wind load on sloped roof with parapet

Jeff,
The conditions to design the MWFRS according to the simplified procedure are listed in ASCE 7-05, Section 6.4.1.1 OR 6.4.1.2. I am not sure which of the 8 provisions of Section 6.4.1.1 are in question.

You can not use the parapets to shield roofing elements. You must assume the parapets are not there for the design of the roof. You then design the parapet under 6.5.11.5.

Regards, Harold Sprague

> From: jeffsmith7@comcast.net
> To: seaint@seaint.org
> Subject: Wind load on sloped roof with parapet
> Date: Sun, 30 Nov 2008 13:21:22 -0800
>
> Say you have a small existing victorian wood building, 30' x 22', 12'
> ceiling with a 22.5 degree roof pitch, 5' ridge height, gable ends, but 2
> orthoganal walls have a 4' parapet (1 foot lower than the ridge.) The front
> gable end and one side have parapets. The front parapet perpendicular to the
> ridge is part of the victorian look and the side is essentially a dutch
> gutter against the property line.
>
> Can this be analyzed using the simplified procedure? For the MWFRS, how do
> you apply the B and D zones to a pitched roof that has a tall wall parapet?
> Seismic will probably govern in both directions for the MWFRS.
>
> Thanks
>
> Jeff
>
>
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> * This email was sent to you via Structural Engineers
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Deletion of ASTM F1642 Airblast Testing from USGS Specs

The option to use Airblast test results per ASTM F1642 to verify a window’s adequacy for meeting UFC 4-010-01 antiterrorism requirements has been deleted from the latest versions of USGS window guide specifications. The only option now is to perform a design analysis with calculations. Why has the airblast paragraph been deleted?

Were any of these problems the reason that the airblast option was eliminated, or is there a different reason?

Thanks,

David Dickey, PE

Lexington, KY

Re: Arkansas

A bedroom to send Bill to, when he mis-behaves.
Gary

David Fisher wrote:
>
> Gary:
>
> Whatcha working on?
>
> "Hillary" wing addition to the Clinton Library?
>
> J
>
> David L. Fisher SE PE
>
> Fisher and Partners - 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.fpse.com
>
> ------------------------------------------------------------------------
>
> *From:* William Haynes [mailto:gtg740p@gmail.com]
> *Sent:* Wednesday, December 03, 2008 12:17 PM
> *To:* seaint@seaint.org
> *Subject:* Re: Arkansas
>
> Yes, the structural was within the Arkansas Fire Prevention Code when
> I last designed there about 2 years ago. It looks like it is the same
> way according to the ICC link given (IBC 2006 plus Arkansas amendments
> is within the Fire Prevention package).
>
> Will
>
> On Wed, Dec 3, 2008 at 7:36 AM, Mike Jones <mike.maryjones@gmail.com
> <mailto:mike.maryjones@gmail.com>> wrote:
>
> On Wed, Dec 3, 2008 at 6:13 AM, Gary L. Hodgson and Assoc.
> <design@hodgsoneng.ca <mailto:design@hodgsoneng.ca>> wrote:
> > Can anybody pls tell me what is the building code for Arkansas? TIA
> > Gary
> >
>
> Based on the IBC 2006 code,
>
> http://www.iccsafe.org/e/prodshow.html?prodid=5441BNL07&
> <http://www.iccsafe.org/e/prodshow.html?prodid=5441BNL07&>
>
> M.
>
>
> ******* ****** ******* ******** ******* ******* ******* ***
> * Read list FAQ at: http://www.seaint.org/list_FAQ.asp
> *
> * This email was sent to you via Structural Engineers
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> * subscribe (no fee) or UnSubscribe, please go to:
> *
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> *
> * Questions to seaint-ad@seaint.org <mailto: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
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>

Wednesday, December 3, 2008

RE: Cost Effective Mechanical Lap Splice?

I was planning to do the same, but the contractor/owner found a source for 7,000 psi concrete. Problem solved!

Thanks for the input, everyone.

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

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

-----Original Message-----
From: Garner, Robert [mailto:rgarner@moffattnichol.com]
Sent: Wednesday, December 03, 2008 3:32 PM
To: seaint@seaint.org
Subject: RE: Cost Effective Mechanical Lap Splice?

And of course, ACI has special requirements for mechanical splices. How will you specify the quality control for the mechanical splices? On Caltrans jobs, we had to send samples to the lab for tension testing.

Bob Garner, S.E.

From: Harold Sprague [mailto:spraguehope@hotmail.com]
Sent: Wednesday, December 03, 2008 3:14 PM
To: seaint@seaint.org
Subject: RE: Cost Effective Mechanical Lap Splice?

I like the Erico's, but you have to be careful with the Dayton's. The last I knew, if you required a #5, you had to splice with a #6 because the Dayton threading reduced the cross sectional area of the bar. The Lenton's use a tapered thread that would develop the full strength of the bar.

Correct me if this is not accurate today. It has been a while since I used a Dayton splice.

Regards, Harold Sprague

Subject: RE: Cost Effective Mechanical Lap Splice?
Date: Wed, 3 Dec 2008 11:54:19 -0800
From: PFeather@se-solutions.net
To: seaint@seaint.org

Dayton Superior Bar-Lock or Erico Lenton Lock couplers

Paul Feather PE, SE

From: Paul Blomberg [mailto:paul.blomberg@gmail.com]
Sent: Wednesday, December 03, 2008 11:36 AM
To: seaint@seaint.org
Subject: Re: Cost Effective Mechanical Lap Splice?

If the lap splice length isn't there, perhaps you could go with a mechanical rebar coupler. If the splice length is close to what is needed, try a higher strength concrete mix and see if the shorter splice length works.

Paul.

Phoenix

On 12/3/08, Bill Allen <t.w.allen@cox.net> wrote:

I'm working on a project where the contractor has installed too short of a dowel coming out of a footing for a retaining wall. I've considered excess reinforcement, but the required lap is still more than what I have.

What is the most cost effective lap splice?

Thanks,

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

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RE: Cost Effective Mechanical Lap Splice?

Hi Harold,

The Erico Lenton threaded couplers are the very best, and we use them as well as the Formsavers and Terminators regularly in new construction. The tapered thread system on the Erico couplers is superb and will fully develop the bars. I believe Dayton Superior went to a system where they provide the lap dowel with an upset end for their threaded coupler because of what you are saying, but we never specify the threaded Dayton Superior couplers and no-one asks for a substitution.

The Dayton Bar-Lock is actually a non-threaded coupler with a series of interior deformations and then special fasteners that when tightened mold the coupler onto the bar. The Erico Lenton Lock is similarly a non-threaded alternative coupler. Since the dowels are existing but insufficient length, a non-threaded solution will be better than trying to thread the bars in the field. For non-threaded applications we see the Dayton product regularly. We do not specify non-threaded couplers for typical new construction because they are much bigger and bulkier than the threaded couplers, but for a wall fix they would work quite nicely.

Paul Feather PE, SE

From: Harold Sprague [mailto:spraguehope@hotmail.com]
Sent: Wednesday, December 03, 2008 3:14 PM
To: seaint@seaint.org
Subject: RE: Cost Effective Mechanical Lap Splice?

I like the Erico's, but you have to be careful with the Dayton's. The last I knew, if you required a #5, you had to splice with a #6 because the Dayton threading reduced the cross sectional area of the bar. The Lenton's use a tapered thread that would develop the full strength of the bar.

Correct me if this is not accurate today. It has been a while since I used a Dayton splice.

Regards, Harold Sprague

Subject: RE: Cost Effective Mechanical Lap Splice?
Date: Wed, 3 Dec 2008 11:54:19 -0800
From: PFeather@se-solutions.net
To: seaint@seaint.org

Dayton Superior Bar-Lock or Erico Lenton Lock couplers

Paul Feather PE, SE

pfeather@SE-Solutions.net

www.SE-Solutions.net

From: Paul Blomberg [mailto:paul.blomberg@gmail.com]
Sent: Wednesday, December 03, 2008 11:36 AM
To: seaint@seaint.org
Subject: Re: Cost Effective Mechanical Lap Splice?

If the lap splice length isn't there, perhaps you could go with a mechanical rebar coupler. If the splice length is close to what is needed, try a higher strength concrete mix and see if the shorter splice length works.

Paul.

Phoenix

On 12/3/08, Bill Allen <t.w.allen@cox.net> wrote:

I'm working on a project where the contractor has installed too short of a dowel coming out of a footing for a retaining wall. I've considered excess reinforcement, but the required lap is still more than what I have.

What is the most cost effective lap splice?

Thanks,

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

Suspicious message? There’s an alert for that. Get your Hotmail® account now.

RE: Cost Effective Mechanical Lap Splice?

Bob Garner, S.E.

From: Harold Sprague [mailto:spraguehope@hotmail.com]
Sent: Wednesday, December 03, 2008 3:14 PM
To: seaint@seaint.org
Subject: RE: Cost Effective Mechanical Lap Splice?

Subject: RE: Cost Effective Mechanical Lap Splice?
Date: Wed, 3 Dec 2008 11:54:19 -0800
From: PFeather@se-solutions.net
To: seaint@seaint.org

Dayton Superior Bar-Lock or Erico Lenton Lock couplers

Paul Feather PE, SE

From: Paul Blomberg [mailto:paul.blomberg@gmail.com]
Sent: Wednesday, December 03, 2008 11:36 AM
To: seaint@seaint.org
Subject: Re: Cost Effective Mechanical Lap Splice?

If the lap splice length isn't there, perhaps you could go with a mechanical rebar coupler. If the splice length is close to what is needed, try a higher strength concrete mix and see if the shorter splice length works.

Paul.

Phoenix

On 12/3/08, Bill Allen <t.w.allen@cox.net> wrote:

I'm working on a project where the contractor has installed too short of a dowel coming out of a footing for a retaining wall. I've considered excess reinforcement, but the required lap is still more than what I have.

What is the most cost effective lap splice?

Thanks,

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

Suspicious message? There’s an alert for that. Get your Hotmail® account now.

Re: Cost Effective Mechanical Lap Splice?

Bill,

In general, my experience is that the cheaper and simpler the mechanical coupler is the larger it is. The Bar-Lock type rebar couplers, where you just put the two bars in a pipe and twist off the nuts, can be rather big and heavy for the larger size rebar. I use these often when concrete cover is not an issue. Remember that ACI and the ICC ES Reports require clear cover to the mechanical coupler not just your rebar. The Lenton taper thread couplers are very small but require a special machine to create the threads. The HRC headed couplers are also small but the trade off is that you need a pneumatic machine to create the enlarged head.

If you go to the ICC ES website and search on rebar couplers you should get several hits. I strongly suggest that whatever coupler you choose it have a "current" ICC ES report as there are a lot of knock offs and copies out there.

Thomas Hunt, S.E.
Fluor

"Bill Allen" <t.w.allen@cox.net>
12/03/2008 11:26 AM
Please respond to seaint

To	<seaint@seaint.org>
cc
Subject	Cost Effective Mechanical Lap Splice?

I'm working on a project where the contractor has installed too short of a dowel coming out of a footing for a retaining wall. I've considered excess reinforcement, but the required lap is still more than what I have.

What is the most cost effective lap splice?

Thanks,

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

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RE: Cost Effective Mechanical Lap Splice?

Subject: RE: Cost Effective Mechanical Lap Splice?
Date: Wed, 3 Dec 2008 11:54:19 -0800
From: PFeather@se-solutions.net
To: seaint@seaint.org

Dayton Superior Bar-Lock or Erico Lenton Lock couplers

Paul Feather PE, SE