When Concrete Forming Gets Messy

Answering tough questions means listening with intent

Arclin recently heard from a customer that one of our concrete forming overlays that was supposed to provide 10 or 15 uses was only lasting for about six pours on some jobsites.  Of course, we immediately set out to discern the issue — and discovered the problem wasn’t with the overlay at all, but was being caused by the concrete, itself. “Changes in the concrete formulations made them much more alkaline, and that was shortening our overlays’ life,” says Arclin’s Product Manager of Plywood Overlays, Gordon White.

In response, Arclin has been working on new overlays custom-designed to stand up to these new mixes.

Product and jobsite changes plus advancing technologies http://www.phpaide.com/?langue=fr&id=16 mean we’re constantly reviewing panniekazino.com and evolving our conform products to ensure maximum performance.  The first step in the process of evolution, however, is…listening.

As a senior account manager with Universal Forest Products in Ft. Worth, Texas, Kirby Mano has a lot of experience listening to customer complaints and expectations. In one case, he says, the customer found that vibrating concrete was damaging the conform panels used to shape columns.

“It turned out to be a very inexpensive fix. The customer just needed to use a different type of vibrator tip to avoid the damage.” Since then, Mano explained, “I’ve been able to take that knowledge to other job sites and prevent problems before they ever started.”

White and Mano both know well, too, that construction job purchasers often base their ordering on cost alone — and that can lead to product performance issues. “You get what you pay for,” White says. “A cheaper panel will not give the same stability or stand up to re-use. When you source these products you have to figure in the strength, the life and the finish as well as the cost.”

Judging the quality of a conform panel takes some know-how, and getting the best panel for your job may cost a bit more. But in the final analysis, the results will speak—and pay—for themselves.

HAO vs HDO: Arclin tests overlays for durability, performance

To evaluate the performance and long-term durability of HDO and HAO panels, Arclin asked Nox-Crete to test four overlays to see how each stood up to tough conditions similar to those in the field.

The panels were drilled for multiple fasteners, damaged by drill bits, gouged, not fully sealed on the edges, left un-cleaned, re-oiled with release agents and used in pours with reactive concrete admixtures.

Then the panels were checked for de-lamination, grain raise and swelling, cracking and overall deterioration.

What did we find?

Of the overlays tested—

  • Arclin 252 100-lb HDO on Douglas Fir face
  • Arclin 252 120-lb HDO on Douglas Fir face
  • Arclin 2600 HAO on Douglas Fir face
  • Arclin 2600 HAO on hardwood face (African Celtis)

—the 2600 HAO product on Douglas Fir and hardwood face veneer far surpassed the performance of the 100- and 120-lb HDO. Overlay durability and concrete appearance were consistently better with the HAO system.


The results
After 21 pours against the 100-lb HDO panel:

  • The overlay surface began to show signs of internal bond failure at pour 21.
  • Significant grain swelling was visible across the entire panel surface at the completion of pour 2.
  • Uniformity in the concrete color was inconsistent from pour to pour.

After 30 pours against the 120-lb HDO panel:

Cracks began to appear at pour 11

Heavy grain swelling and general deterioration were noticeable around the overlay system penetrations

After 30 pours against the HAO panels:

  • Grain raise and damage were well contained throughout the testing.
  • The overlays on both panels were still in very usable condition,
  • The hardwood-faced panel did not perform any better than the Douglas Fir-faced panel.


The details
The panels were treated with two heavy applications of Nox-Crete Edge-Flex 645 edge seal ; the bottom edges were left unsealed.

W.R. Meadows Duogard II form oil was used to oil the panels before the pours.

During the pour, a special funnel was used to divert the concrete directly against a portion of each test panel to simulate conditions that regularly occur on jobsites. An internal vibrator with a one-inch head was used to vibrate the concrete placed against all test panels.

The concrete was left to harden against the test panels at a controlled temperature range of 65 to 75 degrees F for 24 hours.

The test panels were then removed from the concrete, and the concrete was allowed to air dry for approximately two hours, and then reviewed and photographed.

The test panels were placed in a room online casinos where the temperature was kept at 140 degrees F and less than 10% humidity for 48 hours.

Next, the test panels were removed from the heated room and allowed to cool at room temperature for approximately two hours, at which time they were reviewed and photographed.

Finally, the panels were re-oiled—but not cleaned—to prepare them for a subsequent pour.

The following concrete mix was used for the duration of the testing:

  • Cement (Type I/II)                                                                          940 lbs
  • Sand                                                                                              1,009 lbs
  • Gravel                                                                                            1,800 lbs
  • Water                                                                                             330 lbs
  • Water reducing agent (ASTM C 494 Type A/D)                             38 fl oz
  • High range water reducing agent (ASTM C 494 Type F/G)           113 fl oz
  • Water to cement ratio                                                                     0.33
  • Slump in inches                                                                              6 /- 1
  • Concrete unit weight in pounds per cubic foot                             151.4
  • Total concrete volume in cubic feet                                               27

Care & Handling of Conform Panels

Care and handling

Proper care and handling on the jobsite can maximize the life of conform panels and ensure you get the number of pours you expect. Here are some tips:

  • Before first use, coat the panels with the proper form release agent. Arclin recommends Nox-Crete form releases (or equivalent).
  • Clean panels after each use with burlap or flat plastic or wood scrapers that won’t damage the face of the panel.
  • Reseal cut edges or exposed wood, at holes or openings, with two coats of a good quality, exterior edge sealer. (Arclin recommends Edge-Flex 645 or equivalent)
  • Store panels flat and keep them in a protected area before use.
  • Use rubber-tipped vibrators and avoid gouging the panels when vibrating concrete.
  • Use wood wedges, not metal bars or pries, to separate the form from the concrete.
  • When cutting panels, use carbide tip saw blades that are sharp. Make sure the saw is cutting into the overlay (cut with the overlay facing up, to minimize chipping).
  • For form fastening, wood screws are recommended. Pre-drill pilot holes for screws using “screw pilot drill bit” sized appropriately for screw size. These bits are tapered for drilling pilot holes and also countersink the hole to minimize any cracking around screws.
  • Avoid using nails as that may result in cracking of the panel face when the nails are set flush.
  • Ensure proper spacing to allow for panel expansion.
  • Use suitable tape or expandable caulk to seal panel joints.
  • When drilling, ensure all drill bits are well maintained and kept sharp, for drilling tie holes a spur point bit will work well.
  • Use a backing board when drilling panels for less splintering of the panel backs when the bits exit the panel.
  • In hot weather, clean and reapply form release as soon as possible. The form release application will help minimize dry-out of the panel face.
  • When stacking panels, ensure they are stacked face to face.
  • Follow the appropriate pour rate to keep avoid damaging the panel.
  • Lower the panels—don’t throw or drop them—to avoid damaging the edges and face.
  • Remove fasteners to prevent damage and warping.
  • Repair damaged areas with fast drying polyester, polyurethane or epoxy patching materials

Kraft Paper FAQs

Are there any advantages to using Kraft (brown) base paper as opposed to bleached Kraft base paper for concrete form overlays?

Yes, there are two key advantages to the Kraft paper forms: lower costs and lower environmental impacts.

A peer-reviewed study looked at the lifecycle impacts of manufacturing 1,250 tons of natural Kraft paper compared to making the same amount of bleached paper. Manufacturing bleached paper would use almost 800 tons more of wood from approximately 5,800 more trees than the Kraft paper slotseys.com would require.

The additional energy used to make the bleached paper instead of Kraft paper would supply the energy needs of 59 American homes for one year (38 million Btus vs. 33 million.) The total energy required to make the bleached paper would also create over a half a million tons more carbon dioxide than the CO2 resulting from natural Kraft paper manufacturing.

Bleached paper manufacturing also creates much more wastewater than kraft paper –about 15 million gallons more, or enough to fill 23 swimming pools.

In addition, the cost of titanium dioxide, used in the bleaching process, is rising. And according to a report from Dow Chemical, the demand for titanium dioxide should remain strong through 2012. (See http://in.reuters.com/article/2012/07/10/us-dupont-idINBRE86913L20120710

So on both cost and environmental impact, Kraft paper is the better choice. That’s why Arclin uses natural Kraft base paper for all its Medium Density Overlay (MDO) panels. High Density Overlays (HDOs) are available with either bleach Kraft or natural Kraft base papers.

Innovative overlays to meet new demands

As the concrete industry develops an ever-increasing number of mixes to improve performance and for specialty applications, Arclin is keeping pace by creating new overlays to meet the challenges of these new extended formulas.

Among the new mixes gaining in popularity is self-compacting or self-consolidating concrete. Defined as a “high deformability, moderate viscosity” mixture, SCC offers significant advantages in certain building applications, such as in earthquake-prone areas where structures must use more rebar than usual.

Arclin’s Gordon White explains that “thick concrete mixes are more difficult to use in these applications. When you have lots of rebar, it’s very challenging to get access to the mixture to vibrate it and make it settle and set up properly. It takes a lot of time and labor.”

That’s where SCC shows its superiority. “Self-compacting mixes are much more liquid, so they’re easier to pour, require less vibrating to settle, and provide strength that is just as good, if not better, than the thicker mixes.” White says.

But SCC also presents performance challenges for concrete forming panels. These new concrete mix designs use chemical admixtures that reduce the surface tension of the liquid concrete, which makes them more “liquid” and easier to place with less vibration. The result is a better concrete surface. However, the alkalinity of these admixtures also allows They’ll be hitting the scales on from Condition-of-the-Art Slot Machine Game Design to the present Legal aspects of Gambling and Facts of Operating inside a Controlled Business. the liquid to penetrate the overlays faster, resulting in less than optimal performance with most overlays.

“SCC mixes exert more pressure on concrete forming panels because they stay liquid longer than standard concrete mix designs,” White says. “BBOEs can soak up a lot of water and warp; even traditional MDOs can have a hard time standing up to SCCs.”

That’s why Arclin is developing improved high alkaline overlays (HAO) that are more impervious to highly alkaline liquid concrete. Their greater resistance to the liquid concrete allows these panels to absorb less moisture and remain stiffer longer. Concrete forming systems that use HAO overlays can handle the pressure and liquid content of SCC mixes better than forming systems typically used in the industry.

“These new systems are higher in cost but they give a superior finish. Forms are easier to place, and that can reduce labor costs,” White says. “Plus, you get all the strength advantages that SCCs are designed to offer.”

Saving Forests for the Future

From coast to coast, North America was once covered in forests. Now more than 99% of our original eastern forests have been cleared or replaced by second growth, while much of the Pacific Northwest woodlands have been managed with state-of-the-art silviculture and are now truly “farmed”.

Sustaining our natural forests is an environmental imperative in North America today. And Arclin is doing its part.

All of our suppliers use sustainable forest harvesting methods. Sustainably managed online casinos forests are carbon neutral, producing as much wood and carbon as they remove.

Our decorative overlays are printed on papers made from tree fibers grown on controlled, fast growing plantations, sparing old growth trees and exotic woods.

The extended life and cost-effectiveness of our EPIC™ overlay panels make them cost-effective and environmentally responsible. And these panels are available with Forest Stewardship Council (FSC) chain of custody certification and our E-Gen® designation. They may also contribute to LEED MR Credits 2.1 and 2.2 for waste.

The Big Green Story

On the surface, concrete doesn’t seem very ‘green.’ In fact, producing one pound of Portland cement results in the release of one pound of carbon dioxide.

But under the surface of concrete structures being built today lie some ancient techniques and waste materials that, says Matt Dalkie, Technical Sales Engineer for LaFarge North America, “are making concrete a much more environmentally friendly product.”

The secret lies in the use of pozzolans—siliceous material that reacts chemically with calcium hydroxide to form compounds that mimic the properties of cement. Pozzolans such as pottery shards and volcanic ash have been found in the ruins of ancient walls and buildings where they helped strengthen the structures and made good use of what would otherwise have been waste material.

Today, supplementary cementitious materials (SCMs)—such as fly ash from coal-burning power plants, slag from pig iron manufacturing and silica fume from the production of silicon metals and alloys—are used to extend concrete mixes, replacing a proportion of the Portland cement used. And because cement is the most expensive ingredient in concrete mix, that means lower costs.

Not only do these SCMs reduce costs, Dalkie explains; they also improve performance. “SCMs behave differently than ordinary cement. Fly ash, for example, helps to ‘lubricate’ the mix so that it requires less water. That means the concrete sets up faster, is stronger and is more durable.”

Using SCMs also can contribute to LEED credits for lowering energy use and  CO2 production, reducing waste, and recovering structural materials. So too can the use of concrete overlay forms, which offer additional benefits by allowing more re-uses than BBOE, among other advantages.

Dalkie asserts that concrete has another key environmental benefit. “In terms of sustainability, I believe its durability makes concrete the ‘green’ building product of choice.”

Enhanced flow MDO stands up to tough mixes

When it comes to choosing the right concrete forming panel for the job, there is one point that builders need to be very aware of, says Olympic Panel’s Hal Studer:

“This is not your grandfather’s concrete mix you’re working with today.”








Concrete mixes are now more highly alkaline than before. “The most expensive ingredient in concrete is cement,” Studer explains. “So it’s pretty common now for other materials to be added to concrete mixes—things like fly ash from coal burning power generating plants and blast furnace slag from steel manufacturing—that reduce cost and also improve concrete properties.”

To create the type of high-strength, fast-set concrete required by many new high-tech buildings, Studer says, reducing the amount of water in the mix is also critical. “When you reduce the amount of water in concrete mix, you increase the strength, at least up to a certain point.”

The downside? These mixes raise the alkalinity of concrete. And that’s tough on conform panels. BBOEs will give 3 to 5 uses per panel on average; regular medium density overlays will yield 12 to 15 uses each. But with an enhanced or high-flow MDO, builders can get 2 to 5 more uses out of each panel than with regular MDO, thanks to an overlay that is more abrasion- and alkaline-resistant.

Arclin’s Enhanced Flow Medium Density Overlay uses a slightly different resin—and much more resin—than standard panels, giving it greater resistance to the alkalinity of modern concrete mixes. The more resin in a panel overlay, the longer the panel lasts. And, says Studer, “the performance of these panels is more consistent than that of BBOEs.”

Even when MDO panels are priced higher than BBOEs, the cost per pour is reduced by using the engineered panels, according to Arclin’s Gordon White. “If you get 5 re-uses out of BBOE, the cost per pour is about $5,” he explains. “With a standard MDO panel, you can get 15 to 20 re-uses, and the cost per pour goes down to as little as $1.75 per pour, depending on the job and the type of panel used.”

White goes on to say “In recent independent test pours, performed by Nox-Crete,, high-flow panels with Arclin’s Enhanced Flow overlays outperformed the competitive overlay that has been the industry standard.”

These tests used a highly alkaline concrete mix design with a water-to-cement ratio of 0.33. While Arclin’s Enhanced Flow 3369 showed little deterioration after 15 pours, the competitive overlay developed surface cracks after 5 pours and was worn out before the 15th pour White explains.

What To Know

To select the right EPIC™ overlay and ensure the best results, you’ll need to determine:

Concrete mix design
water/cement ratios, chemical admixtures, fly ash, SCC mixes

Surface requirements
coated concrete, exposed, architectural finish, matte, gloss, etc.

Forming systems to be used
loose, jobsite online casino built, gang forms, engineered systems

Reuse requirements
based on all of the above, together we’ll determine the realistic and achievable reuse capacities