Heavy-Duty Adhesive

I don't know, for sure, and do think a visit back to globalspec.com is call for, for I have seen some really cool stuff there that would likely enable what you want to do.

My "I don't know." has to do with Tapcons, which do right well into concrete. Seems there might be a way to hammerdrill the tapcons to hold hooks that went into the 1" slab, within tolerances.

Even if all you did was slather some Mastic that adhered to the back of the veneer, seems to me you would want some mechanical aids, like protruding clips held by tapcons, as an aid.

Again, in this case, I do think there is likely something, and some company listed on Global Spec, that after a bit of trolling may offer either the entire solution, or some things to consider for experimentation with.

To tell you the truth, I am not wild about the dowels and bracing and attempts at accurate settings.

Others may have a better idea, but I'd rather use more tapcons than fewer dowels.

A marble sculptor might know how to route out the back of the 3' by 4' marble so a mount piece held by tapcons would fit in the slot, for instance.

ie. mount bar with tapcons in concrete wall. route out back of marble slab veneer. Apply proper adhesive. Stick veneer to the wall.

The mechanical aspects of tapcons sound like a winner. in my mind, i picture some sort of ledger tapconned into the wall with marble veneer slabs resting on the ledger. all vertical loads would be soaked up by the ledger, and the ledger could be just shy of finished surface.

It seems a lot of large architectural projects use a veneer face over concrete - maybe some research into tilt-up construction finishing, or something similar would help.

I seem to remember the USMA (West Point) has granite faces on some of their buildings, held in place by such a method... although I could be completely wrong.... It might be Annapolis /Navy. (apologies to subsequent branches of military, I know one of you will claim to have done this first!)

I am sure a good concrete person would have some rock-solid (Oy! such a pun!) suggestions.

good luck

JohnnyB

i demo-d a lot of slabs off buildings, then used the marble and travertine for fire-places and house fronts...but never did the stand-up you require....but hereès what makes marble-slabs...5ft by eight, or six by 4 1 nch thick stand and hold in place.

they are set on a 1éith bed joint of a 3sand 1 portland mix...set 1 nch out from the wall. the corners...approx 3 nches in are drilled and dowelèd....I DO NOT KNOW THE WOOD""""BUT THINK ABOUT IT"""SHOULD HAVE MIMIMUM SWELL WITH MOISTURE, oerhaps oak.....vertical dowel holes are drilled lower down than the 3 inchs on top and bottem corners...approx 8 inches

if yr really competant...you may start at laying one slab first away from the cornor, if your corner is not boxed or closed....ièll explain

if your slabs are varied or random sizes...pick yr corner, measure it, mark it out...but do not lay it...if yr cornor is butting to a closed wall....no side thickness visable.... stand it up dry...in place...with a 1 eight wood shimm thet was soaked in water....slide it as near as possible to yr concrete walls cornor---with a one-inch wood block behind, or between yr concrete wall and the slabb...check all plumbs... this is critical...now i doubt thet you have a straight accurate joint where the marble meets the concrete...if not......take a half inch block, and a pencil and drop a parallel line to yr concrete wall.....you can cut this easily with a skill saw and a marble tile dian-mond blade.

if you donèt need to trim, fine...if you did trim....place it dry, on those wood soaked shims....slide in place, drop i inch block s behind top to maintaion verticles.

you may L screw them as prop helpers

so you should have a dry corner slab standing at 90 degrees, plumb...and tailed---with a string line to the far end of the wall....exactly as needed.

now comes the fun part....take a good square piece of two by four anddraw a line approx 1 foot from the top and bottem..on the marble and concrete wall....this is where you will drill yourdowel-holes on the sides...if you want to drill both vertical standing sides.....use 1 foot or 18 inches as a guide....but study the grain of yr slab...you do not want to drill into a long grain fault line thet could crack the slab.

iève seen it in repairedslabs...and will not get into the

if the grain appears weak...go 18 inches on one side....12 on other....again i have not seen yr slabs, nor type ...so ièm validating as much as possible.

you now may have two dowel holes drilled on left side two on right side, and two on top....on the side open from the cornor...where your next slab will butt up to...drill a dowel hole approx 3 inches from bottem into yr slab...if the grain will handle it, its mate is drilled into the concrete wall 1 inch higher than the marble hole.

now...this is the way i have found these slabs layèd up, on demo jobs where i salvaged them....in a 1 eighth bed of mortar...wood dowels pounded into the walls, and copper wire strtching from there to the marble slab...only mortar was at the joints plus one trowel ground-puttied to the back...usually near the center...this allows for plumbing...and tailing to the line-----the dowels connecting the two slabs were just slipped in.....i do not know what tp of wood was used, nor do i know if a preservative would be needed...oor if used thet it would leach....but because the wire used looked like a heavy-12 gauge electrical wire copper, i decided to try some copper gas line, instead of the wood dowels...drill the dowel holes only 5 eights to 3tree quarters deep....if you yse copper for dowels...push a few wires in first then tapp the tubing in place....the one on the bottem is i inch or more higher to allow water condensation to come away from the wall and drip down...i forgot to mention thet the top ones should be slightly higher too...for the samne reason.......sorry if you never read to here b4 starting,,,,LOL

if you pin the cornor dowels in the concrete....and the lengths are ok...butter the slab, bed joint it and slide the slab in place it should slipp right in.

next one is easier.....there are crews thet can lay the middle stone and work to left and right and drill and pin ,and mortor to the line......leave soaked wood shimms at the bottem...they come out late in the day, or tommorrow..then trowel in.

you need drain holes or weep holes in the bottem....more brick and stone wall have collapsed due to moisture condensation behind walls

so you see you can line things up and the blob of mortar burned to the center holds the slab from slippn in...adjusting the wires at the bottem side----and top hold it from falling out, maintain verticles and air-space.

your second slabb butts into two dowels of the first, also mortard and sealing the lower dowel hole...but do not allow the wire to be obstructed from transfering moisture....yr free to adapt the dowling...yet within the lines of proper workmanship,

iève used the copper tubing on walls and arches of field-stone,

ièm just re-reading this....it used to be my trade....due to being a pedestrian in a cross-walk and getting my constitution re-arrranged...i can no longer lift, nor do my trade....ièm amazed though i rememberd as much as this...it used to take three weeks to do what i did in a day..and sometimes ièd only remember i could or did certain jobs,,,but not how...usually in the building code is most of the info...but it is usually minimal.....you probably googled marble...thers a lotof additives and perhaps methods i know nothing of,

i laugh abit to share,,,,after 40 some years the persian saying...if itès of merrit-do it in marble...if not do it in the sand and leave it to the wind and water

good luck

re reading yr request.....consioder if the courses are stacked ar half or third lapped.

i would go with 3 eighs holes, copper tubing, wire...and making sure thet the holes are higher in the wall than their mates in the marble....as yr an enginneer, figures seem ok to me boring those holes three-quarters into marble....ièd pound tubing into the concrete wired holes...pean-expanding the ties---when you do the second and third slab......the copper wire has been simply looped over then back behind the slab between the wall and slab, wrapped around itself and sloped down for moisture

i would guess base is four feet...gives a threefoot course, ièd not be shy going 1 foot from corners....again this is a job i have not seen, nor will...i mentioned salvage from walls thet stood 150 years...the mortar was white portland....the backing central gobb seemed to be plaster of paris , like i say...i marveld at the workmanship

Howabout using Halfen rails or similar?

Install vertical rails to the concrete and then horizontal rails to the verticals. This gets over the tolerance problem. The dowels then simply fix into the horizontal rail.

1" sounds a little thick for a marble cladding panel. Generally I have seen more 1/2" to 3/4".

Try Sikaflex or 3M5200, or ask either company for their advice.

These are one part mastic sealant/glues which are used in the marine industry. They are so strong that a winch (capable of 2000lbs pull) will be irreparably damaged when they try to lift it when it has been sealed with one of these in place of a weaker sealant.

Chas

I would think just about any industrial grade polyurethane adhesive would be well suited for your application. It'll be tougher than most epoxies.

I would suggest you contact Hilti, they have a very knowledgeable staff and some phenominal products. I would suspect their HIT epoxies would meet your criteria for the adhesive.

The 150 system is very good for setting anything in concrete. I recall it was a fast curing two part system - usually have to buy the applicator gun as well. I've used it to tie new concrete slabs to old ones, including airport apron dowels. HIT-HY 150 Fast Curing Injection System http://www.ca.hilti.com/holca/modules/prcat/prca_fuse.jsp?RANGE_OID=30952&MREF=@@@@1094493183.1244751804@@@@

I would also pick Hilti or RedTop......Hilti has a very interesting article somewhere on their web site about their analysis of the concrete slabs that fell from the ceiling of the City of Boston "Big Dig".....held entirely horizontally by Hilti anchors (but with the wrong epoxy or technique)......thousands of pounds should not be an issue.

Simpson strong tie makes a variety of epoxies that are designed to bond steel to concrete in nasty conditions. Additionally a tile mortar that remains flexible across the entire back of the slab would help as well. While the mechanical advantages of the ledger would be an advantage, I cant imagine that the homeowner would want to look at it. you may consider taking some aluminum l metal (3"X1"X1/8") and using it as a blind ledger if you really want to beef things up and still look good. Tapcon the ledger through countersunk holes in the aluminum behind the slabs and then use the flexbond mastic to stick the slab to the wall. Good luck.

There are many large buildings that have marble or granite veneers. Find out who the architect for that building was and contact them.

Masons use thin set mortar

Just for completeness. No one seems to have addressed the main problem (as opposed to solution) here. The difference in thermal expansion of concrete and marble can be found here:-

http://www.fhwa.dot.gov/Pavement/pccp/thermal.cfm

Looks like marble minimum is 4 ppm/°C and concrete max is 13 ppm/°C. So a difference of 9 ppm/°C

and the temperature range for Georgia can be found here:-

http://www.wunderground.com/history/airport/KPDK/2003/1/19/MonthlyHistory.html?req_city=NA&req_state=NA&req_statename=NA

I found a low of -13°C and a high of +36°C.

So over the full 4 foot you are looking at about ½ a millimeter (about 1/50^th of an inch).

Warning/disclaimer: I know nothing about this sort of thing.

I know it's hard work: but I think it's worth reading through GUESTS post #3. It looks as though he's demolished lots of buildings with marble cladding where they've stood the cladding away from the wall on thick copper wire. You could drill "tight" ½" to ¾" holes in the marble on a 1 foot square matrix (that would give each wire a 15 lb load). Epoxy glue the wires in place. Then put some kind of marking ink on the ends of the wires (you may have to move some holes to avoid flaws in the marble), and hold the slab up to the wall to mark the concrete for drilling "loose" holes. You'll need a pretty "stiff" epoxy, other "glue", or, drill deep holes in the concrete and use mortar with long bits of copper. You could use wooden battens to space the marble away from the wall, but, if you used lengths of rubber hose it would be easy to remove.

Finally, or really first of all you need to decide with the customer how he wants the tiles laid out. Clearly the first of these options is the most efficient but also the least aesthetically pleasing:-

There are lots of other options: let the customer decide, but, make sure he understands the cost implications.

Hi Randall,

The difference in thermal expansion of concrete and marble

You're figures are accurate though out of context in that when the marble is adhered to the concrete it's thermal expansion rate will be influenced by the thermal mass of the concrete to the effect the union of each part may balance. Thin set mortar will aid this thermal transference when used as a mastik.

A horizontal groove about one inch depth can be cut using a concrete saw upon the surface of the wall enabling the intermittent placement of steel flat bar to brace the slabs vertically during installation. These bits of steel bar maybe left in after grouting is completed or the slabs may be notched to fit the flat bars if the finish requires a seamless appearance.

You may of course score the edges of the slabs and set the slabs on anchored rails then use mortar as mastik.

This is along the same lines of what I was thinking of, though having cut into a good amount of concrete, or brick, and then thinking of what it takes to get a straight line on the horizontal, digging in an inch with a diamond bladed saw figure maybe there is a reason one contributor simply said masons use ThinSetMortar.

Another contributor pointed out that there is a Grain to the marble that makes routing the back to receive a "ledger", or for lack of the proper term, what I might call a phlanged back bar, that looks like an upside down dripcap, risky.

Does sound as if this is some pretty thick marble and a shallow grove in the back would be helpful if mechanical fastening is worth the effort.

As an aside consideration, I wonder if on this wall there will be a Capstone that inhibits water top down crackout regardless of any perfections of the mortar and wall bonding method used.

Certainly there are tried and true methods for doing most anything, so it is likely that doing something the way it has been done is typically good enough.

Of course some of us are always trying to come up with a better way to even walk.

The 9ppm/°C was assuming that both marble and concrete were at the same temperature: if one side of the wall heated sooner in the morning sun then the difference could be a little greater.

Hi Randall,

I don't know how accurate your figures are, but I wouldn't worry about the expansion over the four feet height I would be much more concerned about the 110Ft length!

Chas

Hi DGCI,

My brother is a pro in the business of marble and large stone panel facing etc.. I'm gonna call him tonight; may put you two together in a PM

You may get some insight here too