Join me, Kelton at Roadware at @ICRIorg’s Virtual Fall Convention #ICRIFall20. I’ve been selected to present in a product demonstration, Less Invasive Crack Repair for Concrete Floors and Structures on October 13, 2020. 2:40 – 3:10PM CST. See a preview of the presentation on YouTube. Learn more about the virtual convention here.
Roadware 10 Minute Concrete Mender™ and Easy-injection mixers make full-depth crack repairs in hairline cracks without cutting. This less evasive crack repair technique breaks the rules for concrete repair.
Broken Rule One Hairline cracks are not worth the trouble fixing.
Broken Rule Two You have to cut open a hairline crack if you want to actually repair it.
Broken Rule Three Crack injection requires pumps, ports, slow epoxy, and lots of time.
Let’s look at these “rules” one by one.
Broken Rule One: Hairline cracks are often dismissed as not worth fixing. However, it’s important to note that almost every concrete crack starts as a hairline crack. Some of these cracks are so tiny that they are not visible to the naked eye.
Cracking naturally occurs in concrete slabs as the concrete cures and shrinks. We use saw-cut control joints to guide the concrete to crack inside the designated joints, but sometimes the concrete cracks in unexpected places. We wish there were an efficient way to fix hairline cracks, but for now, we generally ignore them and attribute them to the nature of concrete. We might reassure customers by saying, “It will be fine; you still have aggregate interlock, and the crack is just on the surface,” or “All concrete cracks, and it’s just the nature of the product.” Unfortunately, customers who have invested in a new concrete floor are usually dissatisfied with these explanations.
The truth is, we would fix hairline cracks if there were a good and efficient way to do it.
Broken Rule Two: You have to cut open crack if you really want to repair it. A repair material has to actually get into a crack so it will actually do some good. Anything short of that is no better than caulk. For the most part, this is true. We can’t repair what we can’t reach. Traditional cut and cover techniques us a diamond blade saw to open up a crack, forming a shallow well for Concrete Mender to accumulate and flow down into the crack. It works really well, and Roadware has been doing it for over twenty years.
What is needed is a way to actively push repair products into hairline cracks. Roadware 10 Minute Concrete Mender can do the job with simple techniques and Easy Injection Mixers. That brings us to:
Broken Rule Three: Crack injection requires pumps, ports, slow epoxy, and lots of time.
For a successful crack injection repair you need to accomplish three things:
The Roadware Easy Injection mixers make it easy to fill cracks as small as 20 mil (0.02 inches) with Concrete Mender. Simply drill a 3/8-inch hole into the crack and then push the almost-water-thin Concrete Mender into the cracks. You can see the Concrete Mender flow along the entire length of the hairline crack. You won’t need expensive injection pumps for this – just a cartridge of Concrete Mender and a manual application gun.
Roadware 10 Minute Concrete Mender starts to thicken and cure in about 5 minutes after application, so the material will stay where you put it. Traditional injection epoxies take hours to cure. In many cases, at the end of the day, the epoxy all ends up under the slab and no longer in the crack.
Roadware 10 Minute Concrete Mender™ with Microdoweling™ penetrates traditional bond lines and repairs concrete from the inside out. This structural polyurethane will not become brittle over time. Epoxy injection resins become very hard and brittle. As the concrete deflects under traffic, the brittle epoxy will start grinding away at the bond-line and the deterioration will start all over again. Roadware 10 Minute Concrete Mender is designed to restore aggregate interlock and deflect with the concrete under heavy traffic and loading. This structural polyurethane will not become brittle over time and is designed to bring the cracked concrete back to original pre-cracked condition.
Getting Started
For many years, engineers have looked for ways to fully inject repair polymers into cracked concrete structures. The general consensus is to seal off the crack with a sacrificial epoxy and install injection ports every few inches. Then thick epoxy is injected under high pressure into the crack with expensive resin injection pumps. The process is time-consuming, the epoxy is brittle, the equipment is expensive and the skill level is highly specialized. This makes epoxy injection slow, expensive and not really effective in the field.
At Roadware, we look for ways to make concrete repair fast, effective and easy.
Fast is better. When injecting Roadware 10 Minute Concrete Mender into concrete, the fast gel and cure time allows you to make a full depth repair from the bottom of the crack up to the top. If the crack you are injecting has a large hidden void, Concrete Mender repairs will start to gel and plug up the void in several minutes. Injection epoxy that takes several hours to cure will sink to the bottom of your crack and pool in the base before it has a chance to cure.
Effective. Concrete Mender is a Structural Polyurethane**. It is about as hard as typical concrete with much greater tensile and bonding strength. It is super thin at 8cps with a surface tension 1/3 of water. It can to penetrate concrete cracks and surfaces. Concrete Mender does not need to be forced into cracks with high pressure pumps and extraordinary methods. Concrete Mender can easily flow into cracks and fissures with just simple manual tools and a specially designed application mixer. You can repair more cracks in less time with less waste then ever before. Repairs are structural in nature and will move with the concrete, not against it like very hard epoxies.
Easy Application. For a repair to be effective in the field, it has to be simple enough for crews to apply efficiently. Installation productivity saves money.
Using Roadware 10 Minute Concrete Mender and Soft-tip injection mixers, you can structurally repair concrete cracks and delaminations with simple tools and methods. This unique system saves time and money and allow for a high production rate for installers. The drill hole/inject method is much less invasive than traditional cut and fill methods and creates a lot less silica dust on the jobsite. The Microdoweling properties of Concrete Mender and Soft-tip Injection promises to be a winning combination for tough concrete repair challenges.
*“Workers may be exposed to dangerous levels of silica dust when cutting, drilling, grinding, or otherwise disturbing materials that contain silica. These materials and tasks are common on construction jobs. Breathing that dust can lead to serious, often fatal illnesses.” The Center for Construction Research and Training. Click here to learn how to work safely with silica.
** Structural Polyurethane: A polyurethane based material that restores structural integrity and aggregate interlock to distressed concrete by using low surface tension and low viscosity to penetrate concrete surfaces and cross-linking polymer chains to bond directly to the concrete-aggregate matrix. This bonding action utilizes capillary forces to self-inject polymer chains into the surrounding concrete. This material should have a modulus of elasticity less than the surrounding concrete and should not become brittle over time. This material may be combined with manufactured sand to form a PCC compatible polymer concrete that can structurally repair concrete cracks and spalls.
General full depth crack repair:
Use the high-penetration abilities of Roadware 10 Minute Concrete Mender™ to make full depth crack repair.
(Fully cured non-moving)
1. Clean out with diamond grinder and remove dirt and dust. Score back spall with blade for a finished look.
2. Flood with Roadware 10 Minute Concrete Mender™
3. Add a fine graded silica sand and additional liquid to grade.
4. Strike off excess material and allow to cure for 10 minutes at 70°F.
5. Open to traffic. Finish and blend with a grinding stone if desired.
Mission critical concrete repairs is what we do here at Roadware. Facilities like city bus garages have areas that are required to be open and operational 24/7 365 days per year. Roadware 10 Minute Concrete Mender™ is your best choice for fast repairs that have to last.
January 18, 2014Dear Roadware,“I am writing this letter in regards to Roadware Incorporated, in particular their 10 minute mender concrete repair product. I have been involved in the concrete industry for 28 years. I am a former Certified American Concrete Institute field testing technician and have been an ACI Concrete Flatwork Finisher and Technician for more than 10 years. For the past 15 years, I have been working to perfect the art of concrete rehabilitation on structural concrete and Architectural concrete. Other repair textures include masonry, slate. granite, clay artworks and architectural stone works.At the 2011 World of Concrete Convention, I met with The Roadware sales staff. I was quite intrigued and impressed with their 10 minute concrete mender product line. I was given some test samples which ultimately persuaded me into using Roadware product.Our first project using Roadware products was a complicated repair contract with a bus transit authority and I had to include a two-year warranty. There would be limited time access during the repair and I needed a product that would withstand heavy bus traffic within hours of application. I submitted my bid using the specifications and MSDS for the 10 minute mender product line and believe this may have been the reason I was awarded the job. End result 10 minute mender works! Fractured concrete, spalled concrete, cracked concrete. Concrete deficiencies e.g. all surface and deep restoration repairs. Microdoweling works period!While I was confident in the product, it is always reassuring to experience it first hand. I am quite familiar with what it takes to provide world class service to demanding customers. Roadware Employees deliver excellent customer service and unmatched product support.”
Sincerely,
William F. Neal
Bothell, WA
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| Sometimes, remove and replace is not an option. Roadware 10 Minute Concrete Mender™ can have this back in service in minutes, not hours or days. |
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| Roadware 10 Minute Concrete Mender™ mixed at a one to one ratio and blended with two parts sand. Each gallon of Concrete Mender makes about 2.2 gallons of repair material. |
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| Roadware 10 Minute Concrete Mender™ can be mixed in bulk with simple tools and equipment. |
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| Manufactured sand or quartz is added to the Concrete Mender to make a trowel-able mortar. |
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| Roadware 10 Minute Concrete Mender™ is available in 10 gallon kits or convenient 2 gallon jug kits. |
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| The Roadware 10 Minute Concrete Mender™ blended with silica sand is poured into the cracks and troweled flat. |
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| Repairs can be made in all seasons with an ambient temperature range of -20F to 100F. |
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| Roadware 10 Minute Concrete Mender™ repairs are ready for bus traffic in about 10 minutes at 70 degrees F. |
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| Customer letter to Roadware |
At Roadware, we see lots of two-component polymer concrete repair products that claim to be just like Concrete Mender™. One even calls it self, “Quick Mender.” They are all basically polyurea based products that are too thick to effectively penetrate concrete surfaces and are so reactive, they become too sticky and gooey to trowel in just a minute or two after mixing. When you dig a little deeper, you will see a very distinct difference in genuine Roadware 10 Minute Concrete Mender™.
Surface Tension:
Surface Tension is a measurement of the ability of a liquid to overcome its own internal friction and penetrate into a material like concrete. Roadware 10 Minute Concrete Mender™ has a surface tension One third of water. It will penetrate concrete cracks and fissures quicker and deeper than water. This low surface tension lets Concrete Mender™ penetrate normal bond lines and allows structural bonding with the aggregate in the concrete. See the electron microscope slide below.
Low surface tension has another little hidden benefit. It allows Roadware 10 Minute Concrete Mender™ to be combined with more than two parts sand and still be workable and trowel-able. Try that with a polyurea and you will have a gooey mess on your hands.
Structural Polyurethane
Roadware 10 Minute Concrete Mender™ is a polyurethane based material that restores structural integrity and aggregate interlock to distressed concrete by using low surface tension and low viscosity to penetrate concrete surfaces and cross -linking polymer chains to bond directly to the concrete-aggregate matrix. This bonding action utilizes capillary forces to self-inject polymer chains into the surrounding concrete. This material should have a modulus of elasticity less than the surrounding concrete and should not become brittle over time. This material may be combined with manufactured sand to form a PCC compatible polymer concrete that can structurally repair concrete cracks and spalls.
Advantages– Due to the very low surface tension of the material and low viscosity, complete saturation bonding of cracks can be easily achieved. Minimal prep to remove loose debris is all that is normally required. This can be considered a structural repair if the material is allowed to gravity flow to the full depth of the crack. Manufactured sand or quartz may be introduced into the repair as necessary to prevent under slab ponding and martial waste. For repair greater than 0.125 inches, specified sand may be added at a ratio of two parts sand to one part mixed polyurethane as the crack is filled to extend the material and add strength. The sand also brings the thermal coefficient of expansion of the repair material closer in-line with surrounding concrete. Polyurethanes of this nature may be applied in a wide range to substreight temperatures making them useful in frozen and cold storage warehouse applications or cold weather application below -20F (-23C). Repairs are typically ready to accept traffic in approximately 10 minutes at 72F (22C).
Toughness:
Roadware 10 Minute Concrete Mender™ mixed with sand gets about as hard as concrete, yet it’s modulus of elasticity is slightly less than concrete so it will move with the slab, not work against it.
Easy Floor Crack Injection using cartridges:
Roadware 10 Minute Concrete Mender can be injected into a wide range cracks and delaminations using a simple cartridge and special Soft-tip injection mixers. Successful full-depth repairs have been made in 24″ of concrete.
Vertical Crack injection
For fast and easy vertical crack injection on walls and structures, we recommend the Gebbie Tech System
THE GEBBIE TECH SYSTEM TRANSFORMS VERTICAL CONCRETE WALL REPAIR
Polishable:
Polishing your floor to a mirror like finish? Repairs made with Roadware 10 Minute Concrete Mender™ will not smear into the surrounding surface or gum-up diamond polishing pads. You can even add natural sand to match the grain and color of the surrounding concrete.
Lower Cost:
By adding two parts silica or quartz sand to a gallon of Concrete Mender™ you will yield about 2.2 gallons of repair material.
A gallon of polyurea or epoxy will yield a gallon of repair material. That makes polyurea more expensive to use even at half the material cost! This does not even factor in the hidden costs of short repair life, damage to the surrounding concrete caused by pre-mature failure, or the cost of redoing the repairs when they fail.
Packaging:
Roadware 10 Minute Concrete Mender™ hand packed with state-of-the-art packaging materials. They have to be good. The very low viscosity and surface tension require it.
Freezers:
Working in the cold? We’re from Minnesota. We know first hand what it takes to work in freezing temperatures. Roadware 10 Minute Concrete Mender™ can be applied at temperatures below -30 F ( -34C). That is really cold. Exposed flesh will freeze in seconds. That is almost too cold to go ice fishing. Most repair products would freeze solid before curing and quickly fail. Roadware 10 Minute Concrete Mender™ generates its own heat. Curing will take several hours, but you will still get the same great performance.
History:
For over twenty years, Roadware 10 Minute Concrete Mender™ has performed without fail in thousands of applications. Many times outliving the facility itself.
| Concrete Mender repair in a cold storage warehouse after 15 years of heavy forklift traffic. |
Utilizing technology developed to repair bomb damaged runways for NATO, Roadware 10 Minute Concrete Mender™ was reformulated and brought to commercial markets in the early 1990’s. You can find us in nearly every industry that has concrete floors, decks, slabs or surfaces.
Links:
Roadware 10 Minute Concrete Mender™
Availability:
Roadware 10 Minute Concrete Mender is made in the USA and is available from Roadware authorized distributors and dealers worldwide. Call 1-800-522-7623 or 1-651-457-6122 to find a dealer near you.
Specifications:
Start out by adding a small amount Concrete Mender to the prepared crack and noting where material in running beyond the slab. Add a light dusting of silica sand or fine quartz to the crack and some more Concrete Mender. The Concrete Mender will combined with the particles of sand to form a quick setting, “mud” at the bottom of the crack. Repeat as necessary and repair the full depth of the slab.
This will be a structural repair with no ports, no pumps, and almost no down time.
ROADWARE 10 MINUTE CONCRETE MENDER™
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| Buildings marked for demolition in Christchurch, New Zealand. |
13. Needle tip mixers are great for better control and pinpoint application. They also can easily clog up when left filled with mixed product. Do not try and force a mixer or tip to clear by adding more force to the gun. You can blow out the rear seals and cause a mess. Get a new mixer or tip and start over.
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| Concrete Mender™ is injected into cracked walls in Christchurch, New Zealand. |
For the first time, Roadware 10 Minute C
oncrete Mender™, the industry’s only Microdoweling™ concrete repair polyurethane, is available in 50ml mini cartridges. The mini cartridge offers precise application control that is perfect for repairing hairline cracks. Each mini cartridge comes with a needle tip mixer and is simple to use. Use the 50 ml cartridge with the Roadware 5150 application tool. Each cartridge will repair about 10 feet of hairline cracks or 3 feet of 1/4 x 1/4 inch cracks.
| Roadware 80105 50ml 10 Minute Concrete Mender™ mini cartridge with mixer and needle tip. |
Use Roadware 10 Minute Concrete Mender to repair and re-bond delaminated concrete slabs.
Roadware delimanition repairs are featured in the July 2008 issue of Concrete International. This is the official publication of the American Concrete Institute. The article was written by Nelson Tonet, President of Express Polymers and a Roadware distributor.
ABSTRACT
“Delaminations in concrete floor slabs can be difficult to repair in a cost-effective and timely manner. A newly developed product (Roadware 10 Minute Concrete Mender™) that uses a two-part hybrid polyurethane with a viscosity similar to water can significantly reduce the difficulty of performing delamination repairs by easily flowing up to 10 ft (3 m) from an injection point and penetrating deep into concrete surfaces. The product also speeds up repair by setting in only 10 minutes, allowing the repair to be checked by sounding only 30 minutes after product placement.”
View full article in PDF format Delamination Repairs PDF
Here is a Roadware synopsis.
Roadware 10 Minute Concrete Mender™ is an excellent choice for repairing concrete slab delaminations. The very low viscosity of less then 8 cps and the exclusive Microdoweling™ penetration properties of the material allow it to flow deep into delaminated concrete voids. The Concrete Mender will restore aggregate interlock and will allow dynamic load transfer under heavy traffic. The expense and mess of pressure injection with epoxy can be avoided.
Two methods of repair have been successful. The first involved dry diamond drilling a 2 or 3 inch (5-8 cm) diameter hole into the concrete slab down to the delamination. Dust is removed with a shop vacuum. Roadware 10 Minute Concrete Mender is poured or pumped into the void. Only one or two inches (3-5 cm) of head pressure is required to push the material as far as 10 ft (3 m) into the delamination. When the material backs up to the top of the hole and the void is filled, silica sand is added and the hole is filled flush with the surface. Soundings are made with a hammer to verify the delamination is repaired in about 30 minutes after application.
Another method is to drill multiple 3/8 inch (1 cm) holes into the concrete down to the delamination. Remove dust with a shop vacuum and inject pre-mixed Roadware 10 Minute Concrete Mender™ with a syringe tipped with a rubber gasket. With this method, you can actually see the material exit the adjacent hole and verify the material is filling the delaminated area. After filling, the holes are blended into the surrounding concrete with silica sand and Concrete Mender or re-drill 1/4″ (5 mm) deep and fill with a color matching concrete mortar.
See the movie:
Both methods will yield good results and are more cost effective than epoxy injection.
