Last week I posed two new videos on the Roadware YouTube Channel showing Roadware MatchCrete™ Clear in action repairing cracks in an exposed aggregate concrete sidewalk and patio. I also posed a video on how to repair a hairline crack in a driveway or sidewalk.How to repair a crack in an exposed aggregate concrete patio using Roadware MatchCrete™ Clear in a 600ml cartridge.
Roadware Flexible Cement II™ is semi-ridged polyurethane for creating flexible bonds between concrete surfaces and other materials. This versatile material may also be used to protect contraction joints from traffic deterioration.
What is Flexible Cement II? ProprietaryPolyurethane Blend
Manufacturing: South Saint Paul, Minnesota, USA
Origin: Designed for creating flexible bonds between concrete surfaces and dis-similur materials.
Function: To flow into concrete cracks and joints. Filling the void with a semi-flexible polyurethane the will accommodate heavy traffic.
Military Use: Classified
Civilian Use: Fill cracks, joints and spalls in commercial, industrial and civil applications.
Service Life: Indefinite
Cure Time: 10 Minutes at 70°F (21°C)
Distribution: Worldwide Distributor Network
Use Flexible Cement II™to repair cracks and protect control joints in parking structures, bridge decks, loading docks, and many types of structural concrete.
Use on industrial floors to protect saw-cut control joints from wheel traffic damage.
Use Flexible Cement II™ to seal cove joints where the floor meets a structural wall.
Seal electrical loops and embedded lighting systems.
Repair concrete thresholds with high thermal differentials.
Flexible Cement II™ is tolerant of surface moisture when applied. Concrete should be as dry as practical to insure a good bond.
Flexible Cement II™ is an excellent flexible adhesive for bonding metal, wood, and synthetic materials to concrete. Use to bond moldings and tack strips to concrete floors.
Bond asphalt to concrete.
Bond wood to concrete.
Bond metal to concrete.
Bond carpet nail strips to concrete.
Bond carpet molding to concrete.
Repairs are tough and can handle heavy industrial traffic.
Use Flexible Cement II™ to protect joints and cracks in concrete bridge decks and pavement where heavy traffic is anticipated. This polyurethane is about as hard as a roller blade wheel and will prevent debris from filling cracks and causing further deterioration of the concrete.
Flexible Cement II™ is recommended for low movement crack repair. This tough material will hold up to forklift and industrial traffic while allowing for some movement. For high movement areas and expansion joints, we recommend a softer caulk type material.
Flexible Cement II™ repairs are ready for traffic in just 10 minute at 75 degrees F (24C).
Bulk mixing Flexible Cement II™:
The passenger tram at this airport gilds on pillows of air. Flexible Cement II is used to prevent the expansion joints from damaging the air pillows.
One of the 12 air pillows that support each car. Flexible Cement II™ prevents metal expansion joints from lifting up and cutting the air pillow as the car passes.
Flexible Cement II™ is used to protect the interface between the metal expansion joint and the concrete. This allows for a smooth surface for the air lift cars to glide over.
Use Flexible Cement II™ to repair sawn contraction joints and cracks
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™.
What is Concrete Mender? ProprietaryPolyurethane Blend
Manufacturing: South Saint Paul, Minnesota, USA
Origin: NATO program for rapid bomb damage repair on runways.
Function: To penetrate deep into concrete cracks, joints, and spalls creating a structural repair in 10 minutes.
Military Use: Classified
Civilian Use: Repair cracks, joints and spalls in commercial, industrial and civil applications.
Service Life: Indefinite
Cure Time: 10 Minutes at 70°F (21°C)
Distribution: Worldwide Distributor Network
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.
Roadware Microdoweling™ Technology:
Slab to slab micro-doweling action, provided by Roadware 10 Minute Concrete Mender, links concrete slabs together, locks them in place and allows for full-traffic, dynamic-load transfer, in 10 minutes. This micro-doweling action is more compatible with concrete and less re-active in harsh environments than even Poly-coated re-bar. Millions of micro-dowels penetrate, then bridge and bond, side by side, broken and jointed slabs. Hairline cracks, trench wide cracks, irregular cracks, cured control joints and variable depth spalls are candidates for this amazing technology.
In 10 minutes, at 70°F (21°C) , this micro-doweled bond has the same compressive and shear strength as poured and fully cured concrete. This makes bond-line failures a thing of the past. Parallel re-cracking, often experienced when epoxies cure out, are eliminated with Roadware’s micro-doweling technology.
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 lose 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).
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.
Common uses for 10 Minute Concrete Mender™
Spalled control joints and cracks.
Spalls and holes.
Uneven slabs and thresholds.
Crack Injection using gravity:
Typical crack injection repair techniques involve epoxy, ports, pumps, and pressure to force thick epoxies into a crack. Roadware 10 Minute Concrete Mender™ with its low surface tension can do same job in less time, less mess, and better performance.
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
Comprehensive testing by Opus International Consultants – repairs have consistently achieved results higher than the manufactured panel.
Full training in the system – a step by step training video and instructional booklet is included within each kit.
Save time and money! Conventional repair methods with epoxy have longer repair times, additional downtime and are more expensive.
Use a hand gun – no need for expensive pumps! The Gebbie Tech System uses the cost effective Roadware 10-Minute Concrete Mender™ hand gun to repair walls.
Complete penetration. Due to the composition of the Roadware 10-Minute Concrete Mender™ the resin travels easily from the injection point.
The approved vertical wall repair system. The Gebbie Tech System is listed in Roadware’s 10 Minute Mender Concrete Data Sheet as the approved method of vertical concrete wall repair.
Repairs cracks from a hairline through to quarter inch. Walls are repaired within 2 – 12 hours depending on the temperature, and the length of the cracks.
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.
The repair pictured above shows Roadware Concrete Mender™ Off-white blended with plain concrete sand and a small amount of portland cement. This water-thin polyurethane is almost translucent. When we add nearly any type of dry sand or aggregate, we get a fast-curing polishable repair that blends beautifully with the surrounding concrete. Since this material is almost translucent, it resists shadowing effects due to over-banding when applied.
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.
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.
Due to the the extended working time formula, bulk mixing of Concrete Mender™ is easy. Unlike polyureas that start to gel up instantly, Concrete Mender will remain workable and flowable for several minutes before curing begins. Much less wasted product setting up in buckets.
With a Roadware needle tip mixer, you can apply Concrete Mender™ within-point accuracy delivering product to where it is needed most. Our needles come as small as 1.2mm in diameter. If you can get a finger nail in the crack, we can get some Concrete Mender in there as well.
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.
Roadware Concrete Mender™ comes in two standard colors. Concrete Grey and natural off-white. Since a typical repair is made up of two parts sand to one part liquid, the color of the sand will determine the color of the finished repair. By adding colored quartz sand to off-white Concrete Mender, you can make custom colors as needed.
We also custom make Concrete Mender in Safety Yellow, Red, Blue, and Black. Use Concrete Mender Yellow to create permanent safety lines and marks in difficult areas like cooler and freezer floors.
Roadware 10 Minute Concrete Mender™ is completely self-reacting and does not out-gas solvents or VOC’s when curing. This material meets FSIS guidelines for work is federally inspected meat and poultry plants.
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.
Use Roadware 10 Minute Concrete Mender™ and sand to repair damaged concrete block walls in an hour or less. Sent in by Dave Wilson at Myspec Integrated Concrete Repair Group in Georgia. 770-335-9123 Roadware 10 Minute Concrete Mender™ is great for repairing cracks and spalls in floors. This ultra-low 8cps viscosity material gravity flows deep into concrete and makes repairs from the bottom up. To repair a holes in a block wall, mix the Concrete Mender™ with fine silica sand to make a trowel-able mortar.
Step 1: Prepare the area and remove any loose block, paint or dirt.
Step 2: Mask off the area like shown. In a clean bucket, mix one part AB blended Concrete Mender with 3 parts sand to make a stiff mortar and trowel into the repair area. You may want to tape a plastic sheet over the repair area to hold the Concrete Mender mixture in place while it cures for 10 minutes. See bulk mixing instructions here.
Step 3: After approximately 10 minutes depending on the ambient temperature, pull the masking and blend in the repair with a rubbing brick.
Step 4: Roadware 10 Minute Concrete Mender™ can be painted as soon as it cures. Paint the repair area to match the surrounding wall.
With Roadware 10 Minute Concrete Mender™ you can do a job in less than an hour that used to take two days. No more waiting for hours or days while traditional cement based materials to set and cure.
Here is a video of using Roadware 10 Minute Concrete Mender™ to repair cracks in concrete or block walls.
One of the most common calls we get is asking how to repair a crack in a driveway or patio. We designed Roadware MatchCrete™ Clear with this in mind. Roadware MatchCrete™ Clear is a UV stable clear polyurethane hybrid that makes effective repairs to most exterior concrete surfaces. By simply leaving the repair clear, the color of the surrounding concrete shows throughout the repair.
The first step to a good looking crack repair is to rout-out or cut the repair open with a diamond blade grinder. You only have to go about 1/4″ x 1/4″. This will create a recess for the material to rest as it soaks down further into the crack. Skipping this step will allow the material to flow uncontrollably on the surface and will create a messy looking repair.
Apply cartridge mixed MatchCrete™ Clear directly to the crack. Small amounts of silica or quartz sand can be added to keep the material from flowing out the bottom of the slab. If necessary, matching colored sand can be used to match colored concrete areas. Fill the crack to slightly below grade to prevent material from flowing on to the surface of the concrete.
After a year of service, the repair above still looks good. Please note, MatchCrete™ Clear is not a soft expansion joint material and should not be used in joints that are designed to move. Always give careful consideration as to why the concrete cracked in the first place and what the concrete is expected to do in the future before making repairs of this nature.
We have a new video for driveway hairline crack repair:
One gallon of Concrete Mender™ will make 2.2 gallons of repair material when typically applied with 2 parts sand. That makes Concrete Mender™ a better value then most epoxies and polyureas. No other product we know of goes as far and performs as well. Any way you look at it, Concrete Mender™ is a better value even it it was twice the price.
Buildings marked for demolition in Christchurch, New Zealand.
Recently, our Roadware distributor in New Zealand requested a list of best practices for using Roadware 10 Minute Concrete Mender™. Contractors in Christchurch are using Concrete Mender to repair many meters of cracks following recent earthquakes.
Keep cartridges in original foil bag and store in
an upright position.
Store on a cool dry place between 10-28 degrees
C (50 – 80 F). If cartridges are allowed to freeze below – 10 C (14 F) some material separation
can occur. Return material to 25 C (75 F)
and shake or mix to re-blend before use.
Handle with care. Punctures to the bag can cause
moisture contamination. Rough handling can cause cartridge cracking and
Ship in upright orientation in original shipping
Read and follow illustrated instructions.
Use gloves and safety glasses. Concrete Mender is very thin and can
splash back if applied erratically.
Make sure the flow-restrictor and mixer seat
Use a new flow-restrictor and mixer every time.
Small cracks less than 2mm should be cut open to
5mm for best results. The 5mm cut
will form a, “well” for the product to accumulate as it soaks down into the
crack and will reduce material spreading on the surface away from the repair
Once material is flowing from the mixer, keep the
tip pointed down. Use the thumb
release on the gun to stop the flow.
Discharge the material from the cartridge
firmly. Working too slowly can
cause poor mixing.
Always apply a coating of Concrete Mender into the crack or spall before adding sand. This will give you better penetration and bonding.
When applying with sand, make sure the sand and
repair area are completely saturated with Concrete Mender.
10. Use a shop vacuum or compressed air to remove as much dust and contaminates from the
11. If you suspect there is water on the bottom of the crack that you cannot remove, repair the bottom half first and allow it to cure (turn grey) before repairing the top half.
12. When working at below 0 degrees C, use a propane torch or similar method to remove any surface frost from the concrete before applying the material. Keep Concrete Mender and sand at room temperature before use.
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.
Concrete Mender™ is injected into cracked walls in Christchurch, New Zealand.
A little Concrete Mender goes a long way. A gallon of polyurea or epoxy makes a gallon of repair material. A gallon of Concrete Mender mixed with 2 gallons of manufactured sand makes 2.2 gallons of repair material. That makes polyurea and epoxy more expensive to use even at half the price.
All Roadware 10 Minute Concrete Mender is manufactured and packaged in South St Paul, Minnesota, USA. We do not private label the product to other companies. The, “patent” did not run out allowing other companies to make Concrete Mender. That was a just an amusing rumor we heard at the World of Concrete put out by an unscrupulous exhibitor.
Microdoweling is more than a funny word. Microdoweling is the process of using very low surface tension materials that penetrate the surface of damaged concrete and bonding to the aggregate within the concrete mix. It is an exclusive Roadware technology. You can see the scanning electron microscope photos in our website by clicking here.
Concrete Mender is a structural repair. Concrete Mender is the flagship product for a new class of materials called structural polyurethanes. It is tough enough to be a structural repair, but never brittle like epoxy.
The color of a finished Concrete Mender repair is more influenced by the sand color than anything else. White silica sand will make a light grey repair. Brown sand will make a darker and warmer tone. We do offer Concrete Mender in Grey, Off-white, Safety Yellow, Target Red, Ikea Black and WalMart red/brown.
Concrete Mender is sold all over the world and most overseas exported product is shipped via air. When your concrete needs to be fixed in ten minutes, you don’t want to wait eight weeks for ocean freight.
When repairing polished concrete floors, you can use polishing dust from the floor, sand and aggregate to give your repairs the same, “texture,” and look of the surrounding concrete.
Contractors in New Zealand developed simple techniques to repair hairline cracks in walls damaged by earthquakes near Christchurch.
In Japan Concrete Mender is known as, “Crack Bond.”
Every cartridge of Roadware 10 Minute Concrete Mender is packaged by hand and inspected by Amanda.