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Hint For HEB - W Flange I Beams

06/08/2015 10:45 PM

Dear Members,

I am trying to find Wide Flange I beams, size about 6" height to use as extra support for compromised balcony concrete slabs.

I need supplier(s) in Florida and a table of admissible loads over different span widths.

For aesthetic reasons I also want to compare load diagrams for squares. meaning square or rectangular pipe with about the same height.

Span will be between 8 and 12 feet.

Needed: up to 120 cuts under angles between O (perpendicular) up to 15 degrees less.

A hint or link is very welcome since I get lost in the translations.

Thank you. D.

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#1

Re: Hint for HEB - W flange I beams

06/09/2015 12:43 AM

Found this....

http://www.thomasnet.com/florida/steel-beams-3634003-1.html

This sounds bad, could you elaborate...

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#4
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Re: Hint for HEB - W flange I beams

06/09/2015 8:57 AM

Everything has been poured about 26 years ago.

The epicor was covered with plastic planks and the ceiling showed rusty leaks.

After removing the cover planks, we found a plastic sheet, collecting rain water that seeped through the slabs. The concrete has lots of (salty) sea sand and the galvanized epicor is gone for 70%.

Leaving 2 rebars #5 as only reliable steel left, plus fibers in the concrete. The remedy is to support the slabs with concrete poles (half cylinders of 10") Integrate the I beams or square pipes under the ceiling after sandblasting the epicor- to divide the slab surface and weight in a safe manner. We also consider a carbon fiber mesh underneath in a thick chemical repair layer. (sort of epoxy plaster)

We still need to decide if we go for I beams or rectangular pipes. (squares)

I am looking for a supplier with a cutting on length service who has a machine. It saves us a fabricator as middle man, since I can supply all the beam lengths to be cut.

Thanks

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#14
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Re: Hint for HEB - W flange I beams

06/09/2015 3:29 PM

Well it seems to me that it would be cheaper and better to just replace the damaged sections of the balconies...this is a common practice here on the beach where I live...in fact we just completed a nearly 2 year long renovation process to the balconies on my building....jackhammers all day long, I had to seek refuge in a local bar and grill nearly every day, luckily I was able to hold up and make it through, hic....they removed all the concrete where air pockets were detected, tapping with hammers on the surface, I can still hear them....no wait,, someones at the door...then resurfaced and/or replaced rebar, and recoated the balconies with several alternating coats of sand, epoxy, then replaced the railings....they also I believe connected all the rebar to an anti corrosion grounding system of some sort...

I'm sure you're aware of this type of repair, just wondering why you have chosen the method you have outlined here rather than repairing the existing structure....just curious...

http://www.bechtbt.com/comm-assoc-article-concrete-balcony-deterioration.php

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#16
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Re: Hint for HEB - W flange I beams

06/09/2015 4:21 PM

Cost, interruption and occupation rate of the building.

They keep always 3 rooms free, where we do the work. This is a silent movie.

The concrete half cylinders are prefabricated and will be cemented and bolted through the walls. The existing slabs don't have the rebar in it as you show, only fibers in the mix. They are tested now to see if the reduced support distance of the slab garanties the required stability.

Now we can do this without a lot of noise, while people come on vacation to enjoy.

(and look how hard we work to improve their hired estates)

The solution does not have to look bad, since the ceiling will have 3 "decorative" art nouveau triangles with typical Caribbean look.

(like the sun in the bible?)

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#17
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Re: Hint for HEB - W flange I beams

06/09/2015 8:06 PM

Frankly, I don't see the existing Epicore panels providing any sort of slab reinforcement value, even when they were new. That sort of panel is only used to act as a slab form primarily. Same goes with the slab fibers, with are only intended to limit concrete shrinkage cracking and not flexural strength. You need reinforcement steel to provide flexural and shear strengths in thin concrete slabs, be they one-way or two-way slabs.

From what I've seen from your photos and from your descriptions, you are far better off replacing the entire existing slab with a properly design one, with properly design girders and columns. What you have here is a engineer's nightmare. That's my professional opinion, but then again, I'm not there and not privy to all the information at your fingertips.

Who the heck designed this quagmire in the first place? Let me guess, an Architect who thought he could perform Structural Engineering? Been there, fixed their mistakes an GodZillion times in the past....

SMH.

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#18
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Re: Hint for HEB - W flange I beams

06/09/2015 11:02 PM

The marketing strategy of Epicor was (perhaps they still exist) just claiming and correctly, that the thick, dovetail formed panel sat in the best position for the lower reinforcement and could replace the steel rebar below. The dovetail made also all kind of easy attachments possible for sub- structures.

Sectional, they had competitive strength and made designing of thinner slabs possible (since with rebar, you lose about the 2 inches for protection)

I used it also in some buildings round 2000, but am I happy that I just considered it the base to pour on.

I netted everything with the fabricated 4 and 5 rebar welded frames below and did the same on the positive side on top over walls and pillars.

Only one of my clients wanted to cover these afterwards with sheetrock. However, I left some small camera holes for inspection (3/8")

In all the other places I have spray painted these underneath an have never used it outside and exposed. I just didn't trust it.

Those days the internet was full of it, but now I can hardly find them.

The engineer who designed the building was also the representative for the Bahamas. I have seen more "masterpieces" with his footprints on it.

I will check if I still find something and let you know.

I spare you even more details here. Thanks, D

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#19
In reply to #17

Re: Hint for HEB - W flange I beams

06/09/2015 11:15 PM

Epicore MSR

The Floor System of Choice in Multi-Story Residential Construction

Designed specifically for multi-story residential construction loads, EPICORE MSR -MSR stands for Multi-Story Residential- has been the leading composite steel floor deck for apartments, barracks, condominiums, hotels, lofts, motels, senior living facilities, student housing, time-shares, and townhouses.

The EPICORE MSR Floor System is a long-span composite slab system utilizing high-strength EPICORE MSR Composite Floor Deck as a permanent and positive reinforcing steel form. The keys to the system are the dovetail rib configuration and the closed ends of the EPICORE MSR ribs.

NOTE: (from myself)

The closed ends are recently added. They were just cut on length before and delivered.

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#20
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Re: Hint for HEB - W flange I beams

06/09/2015 11:49 PM

This looks where the load bearing walls are made of.

They had no damage after many hurricanes. The outer wall has a fiber mesh and stucco, inside sheet rock. All the slabs, except at the pillar under the balcony and one more on the other side of the building are sitting on these. 6-7 inches of concrete plus tiled floors.

The walls arrive from Virginia . The walls come as a complete package with every piece marked and drawings to show where each one goes. The panels weigh next to nothing, I think a 4'x8' panel weighs around 42 lbs. which is less than one sheet of 1/2" OSB.

All in all these panels proved to be quite strong.

(but in years I see a compression of 3/4" to 1" - which caused the balconies to have a wrong slope - water - and probably one of the leak causes too)

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#11
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Re: Hint for HEB - W flange I beams

06/09/2015 3:00 PM

Thank you,

I am contacting some of them to get a basic quote to start with. GA

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#15
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Re: Hint for HEB - W flange I beams

06/09/2015 4:05 PM

The idea is to support this slab after sandblasting the rotten parts of the epicore sheet, that has been used as lower reinforcement steel. Note also that the top beams go towards a wall, but really are not supported there.

These walls are all styrofoam in a steel sheet U envelope.

2 poles will be erected next to the door with on top a H (wide flange beam) that will be the base to carry 2 beams to the concrete post at the outside.

The epicore will be treated to stop rust as much as possible (????) and covered with a epoxy based patch. Perhaps reinforced to reinstate the lower reinforcement with a 4 mm C grid of epoxied carbon fiber into this patch.

New posts will be erected where the beams meet in the 90 degrees angles. (half cylinder)

Ps last picture show a different side of the buildings where the beams have been doubled in size (height)

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#2

Re: Hint for HEB - W flange I beams

06/09/2015 1:28 AM

If you wish to compare shapes, check principally the moment of inertia of each, and then the weight per length.

I couldn't understand this line: "Up to 120 cuts under angles between O (perpendicular) up to 15 degrees less." What are you trying to describe?

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#3
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Re: Hint for HEB - W flange I beams

06/09/2015 8:38 AM

It would be very easy if we have the cuts done by the supplier.

The slabs are triangular and the Beams will show after placement, under the slabs.

They will be resting on new concrete posts and to make them fit, against the wall, under an angle, not perpendicular, they should be cut under an angle.

We need 120 pieces, once we do all the balconies. The lengths are all a little different.

The floor of the balconies have been leaking for years and the galvanized epicore dove tail steel sheets are partially gone. (concrete was poured on these, used as concrete reinforcement)

We have no saw machine to cut all these lengths out of 40 feet lengths, and we look for a supplier who can do this for us, before being shipped to the Bahamas.

There is no supplier here. So Florida in general is easiest. Ft Lauderdale, Miami, Jacksonville have shipping lines to here.

I hope this is clear and can eventually make a drawing somewhat later. Thanks. D.

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#5
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Re: Hint for HEB - W flange I beams

06/09/2015 9:26 AM

I'd suggest just checking Steel suppliers for those areas, either online or Yellow pages and then call/email your request for quote.

Any proper steel supply will have at least a horizontal band saw that can handle more than 6" height and they usuually have a nominal cutting charge. The one thing is, it sounds like you may want a slight draft angle on the ends? That is easily done- just cut the beam on its side, set at the correct angle to blade- but needs to be clear beforehand.

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#12
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Re: Hint for HEB - W flange I beams

06/09/2015 3:07 PM

Like a skipper who has everything at home, it is the same with me.

This is almost a survival experience when it comes to supplies and exorbitant bills.

My shop however is 6,000 miles away. Thanks

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#6

Re: Hint For HEB - W Flange I Beams

06/09/2015 10:08 AM

Right now I'm working as Maintenance Supervisor at a steel fabrication shop. We have one horizontal band saw that operates all day long and has a PLC that reads operator input.

Simply said, you program the saw and it cuts what you programmed I.E. length, angle, all done automatically. The saw is loaded by crane with raw material up to 100' long but typically only 40' lengths are our standard length.

Any fab shop that does work for the building industry would have exactly what you need and can cut the parts you need.

As for the steel shape and size! I would be talking to an engineer that will spec out exactly what you will need, but that isn't always visually pleasing! (they want it to be structurally sound, not pretty) Discuss your ideas with the engineer and have them give you a few choices of material shape and size.

I have seen several earthquake repairs on concrete balconies in California and like I stated, they were structurally sound and very ugly. They worked, but a little thought of aesthetics would have gone a long way to the overall look of the building. I know the reason it was done like that was because the building was in a very depressed part of downtown Los Angeles and they went CHEAP on the insurance repairs.

Good luck.

Bryan

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#7

Re: Hint For HEB - W Flange I Beams

06/09/2015 10:11 AM

dvmsdc, you're going to need to provide much more detailed information in order to properly size the beams to carry the Design Live and Dead Loads. The Local Code Enforcement Officer may also require you submit a set of detailed plans with sections & details, all signed by an Architect or Professional Engineer. Be prepared to have the construction inspected by the local LEO/Building Inspector.

Needed info:

A layout plan, drawn to scale, showing the locations of each new beam, the existing walls, and new support columns.

Spacings between the beams. You'll also need to know the existing slab load carrying capacity in order to determine the maximum spacing of the new beams. Do you have a copy of the concrete slab details on approved construction plans? The need to state the bar sizes, spacings, depths inside slab, orientations, bar grade, and required 28-day design concrete compression strength (in psi).

Length of each beam.

Thickness of concrete slab, ID and thickness of existing steel decking/pans, and ID and thickness of any overlayment material. Anything other material and constructs supported or hung from the slab and new framing (like lights, mechanicals. and electrical). A Dead Load allowance in the design must be made for all of these materials.

Are the new beams top flanges going to be physically attached to the underside of the slab/steel decking w/ Expansion Anchors? Simply gluing the top flanges to the underside of the slab won't suffice. I recommend that you do this to reduce the "Laterally Unsupported Length" of the beam compression flanges (top flanges) and thus are able to reduce the maximum bending stresses and resultant beam size/weight. Also, due to slab flatness issues, you may have to stuff a low slump non-metallic non-shrink grout between the top flanges and slab underside.

State of Florida Building Code Live Load allowance (in PSF) for exterior balconies and decks.

This design is something you just cannot "wing it". Hopefully the Steel Fabricator will have a Structural P.E. on staff or on retainer. I recommend that you do not try to "size" these new beams by yourself,because if you do, you may under-size the beams.

Believe me, do it the correct way by seeking professional help. I really mean that. If you don't, you will be legally liable for physical damages and injuring/killing people because of a structural failure. Also, most likely your homeowner's insurance won't cover such a failure.....you'd be on the hook criminally and monetarily. I've done hundreds of these types of projects over the years. I've also performed Forensic Engineering investigations on many failures where people did a "Guess-by-God Approach" by doing it themselves.

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#9
In reply to #7

Re: Hint For HEB - W Flange I Beams

06/09/2015 1:02 PM

The structural liability has been taken care of. That is my job right now and I have also a structural engineer working with me who is licensed. I have been part of the engineering committee also when I designed and constructed many mansions here. Stopped a few years ago because of the contribution fee.

My problem is just to find the right names and surrogates for HEB and HEA wide flange steel beams and someone who can supply them cut on size.

To compare the load capacity and eventually the same for a replacement square beam, where the size matters (height, thickness, base and corner radius)

Before I had them imported from Europe with on top styrofoam blocks to fill up the containers.

The balconies or terraces on several floors have one post underneath on the outside.

Nothing has moved yet, but it will in several years if nothing is done now. Static and dynamic loads are within safe standards when HEA 160 is used.

However a HEB has a far better look and a square pipe is the nicest for the finish.

Some manufacturers also supply an I beam with a thick wide flange at the bottom and a thinner one on top.

Poles: (10" PVC pipe poured with concrete avg 2200 psi and reinforced in the center with 4 rebar 4 and sturbs - these are 9 feet high)

The basic framework of the building is a pole concept, that bears the monolith slabs, together with the walls.

In the buildings I have built I also used Epicor steel decking, but only to have a base to pour the concrete slabs on and inside of buildings and with the ceiling exposed for follow up.

While epicore is a nice concept, it doesn't last without a lot of preparations and maintenance because it starts rusting away in no time. When I calculated the beams and slabs, I just ignored the epicore and used rebar reinforcements on top.

While the 58.000 square feet building was built, a building department inspector was there 24/7 and passed all the code requirements. The building code in the Bahamas is a lot more strict than e.g. in Florida. (we have plenty of hurricanes and the buildings last- old buildings can lose the roof and that's it)

I am monitoring all the concrete spans and when they show defects, they are supported with more poles or redone. (found beams here with a spam of 30 feet - 8 inches thick with 2 #5 rebars it and above the center - impossible, but it lasts 25 years now)

I can critisize the whole concept, but that doesn't help the owner. The goal is to give it another 25 years in acceptable safe condition for tourism and occupation.

The building, I guess is a kind of experiment, since all the walls are styrofoam sandwiches of 5" thick in a metal sheet envelope. (they carry the slabs too - howvever I doubt the long term stability)

Since these parts are not exposed to the elements, the epicore is preserved far better.

Pics will follow asap. Tks

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#8

Re: Hint For HEB - W Flange I Beams

06/09/2015 12:39 PM

CaptMoosie offered some very good advice. Furthermore, you may have to design for hurricanes, whatever that means. I live in Northern Michigan, we don't get many of those up here.

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#10

Re: Hint For HEB - W Flange I Beams

06/09/2015 2:10 PM

Good to hear that you have a Licensed PE aboard to help you out. I hope your engineer is an experienced Structural eng.guy, and not a plain vanilla-wrapped Civil. Not all P.E.s are created equally.

Okay, I was under the impression that you were the Owner. Apparently not....my Bad.

Doesn't your engineer know of local steel fabricators that can provide you the steel?

I probably could look it up myself, if I knew what town you're in or very near to, BUT not my job mon.

Your request for "admissible" load diagrams is really a NO GO. They don't exist really, unless you want to use the AISC ASD "Allowable Moments in Beams" charts for 36ksi and 50ksi steel wide flange beams, and they're approximate based on a few assumptions and other conditions. One size doesn't fit all conditions, so-to-speak. No such critter exists for square tubing. You are better off having the engineer perform the calculations for both types of steel members (WF vs. TS).

Be very careful what you are doing here by installing new steel beams to support the slab. You need to have rebar running perpendicular to beams, usually in 2 layers. One layer of bars in the top of the slab as it runs over the beam to handle Negative Bending Moments, and a bottom located bar layer between beams to handle Positive Bending Moments. You cannot just inject beams willy-nilly to support a slab if this condition doesn't exist. You may actually hasten the demise of the slab if the two rebar layers are not present. Your P.E. should know this. I sure hope he/she looked into this condition.

I'm still having difficulties envisioning the current conditions. Recent pics would be incredibly helpful.

Also, do construction plans exist of this slab and the rest of the building, and do you have access to it so that your engineer can evaluate everything, etc etc etc?

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#13

Re: Hint For HEB - W Flange I Beams

06/09/2015 3:27 PM
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#21

Re: Hint For HEB - W Flange I Beams

06/09/2015 11:55 PM

Where in FL isn't mentioned but with the final destination being the Bahamas is the East coast the preferred location for the steel and the shipping point?

Dimensions of beams: http://www.engineeringtoolbox.com/american-wide-flange-steel-beams-d_1319.html

Allowable loads: http://www.engineeringtoolbox.com/w-steel-beam-uniform-load-d_1722.html Have your structural engineer review these for compliance with local codes.

Southern Florida suppliers of Wide "W" Beams and steel services:

http://www.metrosteelfl.com/ Tavares, FL

http://www.tampabaysteel.com/metal-products/structural-steel/ Tampa, FL

http://www.dixiestructures.com/ Labelle, FL

http://www.southernmachineandsteel.com/ Ft Meyers, FL

Contact any of these for the loads of other shapes and sizes.

Good Luck, Old Salt

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#22
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Re: Hint For HEB - W Flange I Beams

06/10/2015 12:10 AM

That is worth a quick good answer . From Jacksonville to Miami is most convenient.

According my findings a HEB 150 (eur - approx 6") does the job, but the toolbox starts only at 8", considerably higher web.

Thanks. D

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#23

Re: Hint For HEB - W Flange I Beams

06/10/2015 2:34 AM

Moosey is setting you on the right path here.

My 2 bob's worth is to not use hollow section for your columns. Use an H beam.

You want to be able to see if there is any corrosion and hollow section rusts from the inside out.

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#24
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Re: Hint For HEB - W Flange I Beams

06/10/2015 8:24 AM

That is correct.

If the owner want the hollow squares, we certainly will need to close these with weld on pads. G.A.

Personally I prefer W beams with a hot dip galvanize layer.

D.

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#25
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Re: Hint For HEB - W Flange I Beams

06/10/2015 9:42 AM

Having been at this for over 30 years in coastal Florida, my initial questions:

Does this condition extend to the interior of any of the second floor spaces?

Has there been a cover meter evaluation or trial excavation from above to try to detect the presence of dedicated rebar reinforcement in addition to the severely corroded cold formed left-in-place steel form work?

It would appear that if the extent of corrosion of the very thin cold formed steel is as it appears, this material most assuredly should be so deteriorated as to provide very little bond to the concrete and have so little remaining tensile cross section as to afford insufficient structure to be the primary tensile steel for the concrete deck above.

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#27
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Re: Hint For HEB - W Flange I Beams

06/10/2015 11:56 AM

I am in full 100% agreement with bulladrr.

Due to the present advanced deteriorated state of the Epicore panels, they cannot be relied upon to have any appreciable bond strength with the overlying concrete slab. I strongly suggest that any structural analysis to determine the load carrying capacity of the slab should discount the presence of the Epicore panels to provide a "transformed" composite section.

I am totally shocked that these slabs have no steel reinforcement, and have relied solely on fibers (what type, wgt. and amounts?) to aide in load-carrying. That is not physically possible. I am equally shocked that none of slabs have catastrophically failed under any implied Live Load, namely the presence of people on them, w/o any steel reinforcement embedded in the slabs. The building's owners have been incredibly lucky thus far.

What do the Approved Construction plans depict in that slab? Any rebar? What does the Technical Specifications denote in terms of the same? Have any photographs taken during construction of these slabs survived, and if yes, what do they depict? Does anyone involved in this construction have any surviving shop drawings, particularly regarding rebar?

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#29
In reply to #27

Re: Hint For HEB - W Flange I Beams

06/10/2015 4:10 PM

I didn't want to make a picture of the side we are working.

The slab, tiles included, is 5" thick, the top of the dovetail is 1" up. The beam that surrounds the slab is only 6"1/2 high with a 40 degrees slope. That is different with the pictured side. (and has no post to lean on - floating beams from the 80's ?)

The fibers I agree will not do the trick. While the epicore did. It is now gambling time, not about if, but when it comes down. I have jacks underneath, just in case.

Plans refer to 2 rebar 5 in these beams. I find nothing for the slabs, except the epicore.

No retro pictures. I agree that luck is involved and wonder what an exceptional party gang load could have done, other than 2-5 occupants sitting there. They say - it was good for 25 years already -

I still did not make a final decision yet, since a lot more has to examined first. If I decide to reinforce with beams and rebar and 20 people live load, the lowest candidate is a W6 x 25 and all higher web ones better.

Span between the walls is 11'6'.

I keep you posted. D

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#31
In reply to #29

Re: Hint For HEB - W Flange I Beams

06/10/2015 9:16 PM

So, it's presently a cantilevered balcony, right? (With acroprops for Justin)

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#28
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Re: Hint For HEB - W Flange I Beams

06/10/2015 3:34 PM

I have a Bosch metal detector that can give me information about the width and depth of the (eventually) steel inside.

I can also do some core drilling and work 2 ways:

If I isolate the machine I can get a ground from steel to the drill, before I drill through the rebar (if any) The machine doesn't "see" rebar and also doesn't feel no difference drilling concrete or steel or a mix of both.

I am very reluctant to use a jackhammer there, because I don't feel confident about the walls either.

The dove tail grooves are pretty big and perhaps I can cement some rebar in it. It can only get a better grip in time since all the steel expands with rust (?)

Problem is that the walls are styrofoam with a thin sheet of envelope on top.

Once we are in the building, away from the terraces, we find no alarming form of corrosion. As far as bond with the concrete, I don't make myself happy.

Both are minimal.

Peeling off the epicore however doesn't work because of the dovetails, and there is also less rust in there. The epicore is normally more than 1 mm (1/25 th in) thick when new. At least you convinced me to do some extra research first. G.A

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#32
In reply to #28

Re: Hint For HEB - W Flange I Beams

06/11/2015 11:24 AM

Puzzling.

Can you send along a close up of the "dovetials" showing geometry and layout? I can see no dimples in the pans on the photos that would have indicated an array of bonding "stud" insertions between the pans and the cast concrete slab.

As far as I recall, the Bosch meter, or at least the ten year old one I have, is limited to reliable detection of rebar of the No. 5 variety to about 3 inches on a good day. Also, the the layer of steel on the bottom of the slab may confound the reading or detection of any rebar above the pan layer. More advanced devices, such as the Profometer, will detect both from above, but will numerically show a blip where there is a rebar above the steel pans, although the actual depth to the rebar may be a bit whacky due to the combined rebar-pan detection. If you are using the Bosch, of which I am familiar, the best bet is to remove some portion of a pan and see what you can detect from below.

Adding external structural steel of any variety other than stainless will require all manner of protective coatings. I have had a somewhat better experience with metallizing than hot dip galvanizing, provided certain procedures are followed by the metallizer.

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#33
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Re: Hint For HEB - W Flange I Beams

06/11/2015 2:13 PM

With the Bosch DME 10E the results were not very reliable.

The backing sheet at the bottom seems to interfere a lot with the readings. I cannot find a pattern that even points to rebar in it.

The answer (as off topic - one of the last ones to Capt. Moosie) has a picture of the epicore product as it comes new. I can always make one on the site too if you like.

Dimension of the dovetails are approx:

Width of the top: 1 1/2"

Height: 2"

Width at the bottom: this varies a little, since it depends how far you stretch the panels out.

Typical between 1/2" and 3/4" = I measured most 5/8" on these surfaces.

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#34
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Re: Hint For HEB - W Flange I Beams

06/11/2015 4:39 PM

It sounds like the embedded dovetails may be still significantly bonded to the concrete, pretty much doing the positive flexural reinforcing for the slab. Some exploratory grinding could be very revealing. If the dovetails are not corroded to the point of scale development, an option may be the insertion of #3 MMFX2 rebar into the dovetail slots after pressure cleaning. Shoving a good overhead repair mortar from guys like Euclid, BASF, Sika, etc. into the slot, then inserting the #3 may work, maybe in two steps with a plywood batten on edge to secure the bar against the top of the slot until the first batch of mortar sets, holding the bar in place, then filling the slot to flush with the bottom of the slab. (I would still grind off the rusted panel facets at the dovetail edges.)

Fun job. Wish I knew where it was to have a look.

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#35
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Re: Hint For HEB - W Flange I Beams

06/11/2015 7:30 PM

This is indeed an option we consider doing. You should join the club.

Even if the rebar will expand while rusting, the bond will extend till the concrete around the dovetails will crack.

(years to go)

Problem however is that the slabs are resting on the side on walls I have send pictures of as reply to Capt. Moosie.

Styrofoam in a light metal envelope at the borders. ( I cannot even call it a frame because too light)

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#36
In reply to #35

Re: Hint For HEB - W Flange I Beams

06/12/2015 9:02 AM

You should check MMFX2 - rust is not a concern for this rebar. Also, it is about 50 per cent higher in available tensile capacity compared to Grade 60.

The slabs bearing on walls should not be a problem. On the longer spans, the No. 3 can flex and be inserted in the dovetail cavity over the walls filled with fresh overhead repair mortar. On the shorter spans, there should be enough room in the dovetail for a dowel lap near the wall. For protective cover, about 15 mm of cover should be enough for MMFX2. Also, a second finished cover round of mortar at laps could be an epoxy sand grout, but unless the contractor is experienced with such, the epoxy manufacturer rep should be on hand for the first application.

I am beginning to feel like I have been hired for the job.

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#26

Re: Hint For HEB - W Flange I Beams

06/10/2015 11:42 AM

You need to goggle AISC (american insitute for steel construction). See how much they want for their handbook. Lot 's of good info including beam tables in it.

As for where to buy, almost any steel warehouse can get it or will have it.

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#30
In reply to #26

Re: Hint For HEB - W Flange I Beams

06/10/2015 7:27 PM

You can also find them on Ebay and Amazon.

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#37

Re: Hint For HEB - W Flange I Beams

06/15/2015 4:28 PM

I think you might be better off buying an abrasive wheel cutoff saw (around $250) and make the cuts on-site. This will ensure everything will fit as it should. I'm certain if you have the steel supplier do the cutting, some of the pieces will not fit as planned. I'm sure the supplier will be charging you for the cuts anyway.

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#38
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Re: Hint For HEB - W Flange I Beams

06/15/2015 6:39 PM

Do you mean for the W6 X 25 or the rebar?

The Beam cut is 7.3 in2. I wonder if one abrasive wheel will do one cut. And how many cuts for a machine life. I have build a 53 Ft yacht out of 1/4" steel (hull) with just a hand machine and everything is possible, 40 years back, but never again.

They are also terrible noise makers and when a wheel gets stuck cracks in that beam, I don't want to be in town.

I think these are useful on the site for thin wall channels and for emergencies. Thank you. D

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#39
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Re: Hint For HEB - W Flange I Beams

06/16/2015 5:15 AM

I think Ron was suggesting fabrication in situ.

Maybe a drop saw with an abrasive cutoff wheel is uneconomical or too slow for 7.3in2?

Is that the total cut area of all the sections that need fabricating?

A band saw may be the answer. I agree with Ron that on site cutting removes a couple of steps where things can go pear shaped and you also have the means to rework without delay as required.

Unless you are super sure you can get the design right and fully documented and find someone to do it right as well then ......I dunno.

I have a close friend here with an engineering facility where he can work on very large complex fabrication specs or go fully mobile for on site bespoke fabrication as required.

Some jobs work off the plan with almost no risk others are best done in situ.

Renovation V new build is a big difference.

My opinion.

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