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
Formulation: Classified
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
Exterior Repairs
Use Flexible Cement II™to repair cracks and protect control joints in parking structures, bridge decks, loading docks, and many types of structural concrete.
Control Joints
Use on industrial floors to protect saw-cut control joints from wheel traffic damage.
Cove joints
Use Flexible Cement II™ to seal cove joints where the floor meets a structural wall.
Electrical Podding
Seal electrical loops and embedded lighting systems.
Thresholds
Repair concrete thresholds with high thermal differentials.
Moisture
Flexible Cement II™ is tolerant of surface moisture when applied. Concrete should be as dry as practical to insure a good bond.
Concrete Bonding
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.
High Traffic
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
Formulation: Classified
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:
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 10 Minute Concrete Mender can be bucket mixed and applied like or mortar.
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.
Scanning electron microscope image of the interface between Concrete Mender™ and concrete.
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.
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.
Common uses for 10 Minute Concrete Mender™
Spalled control joints and cracks.
Spalls and holes.
Delamination Repair
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.
Slowly injecting Roadware 10 Minute Concrete Mender into 24″ of concrete using 600ml cartridge and soft-tip injection mixers.
The core sample shows full depth repair down 24 inches.
Hairline cracks repaired using Roadware 10 Minute Concrete Mender and Easy Injection application.
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.
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.
Polished concrete repair with Concrete Mender™ Off-white.
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.
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.
4030 Grit manufactured quartz sand is the standard sand used with Roadware 10 Minute Concrete Mender.
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.
Bulk Application:
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.
Roadware 10 Minute Concrete Mender can be easily mixed in a bucket with sand or used neat. No pumps of special equipment needed.
Pin-point Application:
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.
Use Roadware needle tip injection to repair hairline cracks in concrete floors.
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.
Colors:
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.
Use Concrete Mender Off-white to make your own colored repair by adding different colored sand at the time of application.
Specialty Applications:
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.
Safety:
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.
History:
For over twenty years, Roadware 10 Minute Concrete Mender™ has performed without fail in thousands of applications. Many times outliving the facility itself.
Supervalue warehouse cold storage floor repairs with Concrete Mender™.
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.
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.
From the Roadware Crackrepair Fax Newsletter August 17, 2004
Tricks of the Trade
Hereʼs one you can warm up to. While installing 14 cases of Roadware Flexible Cement II (thatʼs 168 tubes), Roadware contractor Dave Wilson got tired of shaking and turning tubes, waiting for the ball bearings to start clicking. Dave headed over to a Super Wal-Mart looking for an electric blanket. It was the wrong time of the year, but they did have heating pads.
Dave had this crazy idea if they warmed up the cartridges, the material would mix immediately, speeding up the installation and keeping the installation virtually striation clear. To make a long story short, he got that and a whole lot more.
The heating pads exactly fit the boxes of Flexible Cement II™..
Open the bottom of the box, remove the bubble packing and insert a heating pad.
Open the top and place an additional heating pad on top of the cartridges.
Turn the pads on to medium/medium high.
Wait 15 minutes.
Take out a layer of cartridges (3) and place the pad on the next layer.
Shake the three cartridges until the white side has a consistent color. You will hear the steel ball rattle inside. Set up the three cartridges and run out 10-15 feet of expansion joint or construction joint with FLEX II.
Have second crew member follow behind with a second application and a third crew member follow with a third application.
At the end of the third application leave the nozzle stuck in the joint to dam the warmed FLEX II.
Set up three more cartridges and continue the run until complete.
The warmed FLEX II will self level, require no additional trowel work and if done carefully, no clean-up needed. Pull the nozzle-dam and replace it with FLEX II as you start the next run. This will eliminate cold joints.
When breaking for lunch, reduce pad heat to medium.
Dave’s Comments: “Iʼve never heard the ball bearings rattle before, but I hear them now. This puts cartridge applications on a par with bulk-mixed FLEX II. Itʼs quick, easy and very effective. The material thins to Mender-like viscosity and penetrates joint walls securing the FLEX II and the joint. The pads may be reused, of course, and the set-up cost is minimal.”
“I highly recommend you try it. It sure worked well on this job and we will continue to use a little heat to keep things flowing.”
Roadwareʼs Comments: “Why didnʼt we think of that?”
Electric heating pads are a good way to warm up Flexible Cement II prior to application. Use caution not to “cook” your cartridges for more than 12 hours. Leaking at the seals may be the result.
Stop repairing polished concrete with polyurea joint fillers. They look like plastic, do not bond well, and do not hold-up over time. Concrete polishing lets the natural beauty of stones, sand, and rock shine through. Your repair product should as well.
We took the provenMicrodoweling™ properties of Roadware 10 Minute Concrete Mender™ and combined it with natural sands, aggregates and pigments to make repairs that not only look great, but perform better than epoxies and polyureas.
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.
Question: How do you epoxy inject cracks in floor slabs on grade when you do not have access to the bottom of the slab? What keeps the product from running out the bottom and all over the place?Answer: We make these type of repairs all the time. The first thing to do is dump the epoxy. It is too thick, too brittle, and takes too long to set. Fast setting materials like 10 Minute Concrete Mender allow you to control set points deep in the crack and prevent material seepage.Roadware 10 Minute Concrete Mender™ has an ultra low viscosity of 8cps and will gravity inject into the smallest of cracks. We make the repair in stages adding fine silica sand into the crack as necessary to prevent the material from running out the bottom. The product can be injected with needle tip mixers as small as 18 gauge. With careful technique and experience you can make structural repair that will restore aggregate interlock and restore the slab.
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™ needle tip application.
This floor was repaired by troweling down a thin layer of Concrete Mender and sand, then ground smooth. A liquid hardener completed the restoration and the floor was polished.
The floor shows zero failure shown here 3 years later in 2007. The floor continues to perform today.
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.
Why are my contraction joints spalling and what can I do to stop it?
Contraction joints (or control
joints) are joints cut into a slab shortly after pouring. The purpose of these joints is to control the cracking of the slab as it cures. Most concrete slabs shrink and sometimes curl for the first 12 months after pouring. Contraction joints allow the
slab to crack at pre-determined intervals instead of natural random cracking. Joint filler is used to protect the joints from spalling and chipping caused by traffic on the slab.
As the slab cures for the first
12 months, it shrinks in size and may even curl up at the joints. The contraction joints will expand as the slab shrinks. This causes the joint filler to split apart or dis-bond from the sides of the joint leaving them exposed to traffic.
When loads are rolled over the
joint. The force of the load has to transfer from the wheel, to the concrete, and to the base. If the slab is even slightly curled and the joint is expanded, the force of the load will impact on the joint causing cracking and spalling. You may even get stress cracking parallel to the joint. You can sometimes feel the uneven load transfer across the joint if you stand with one foot on either side of the joint and have someone else roll a heavy load across the joint.
Eventually, you get a spalled contraction joint. The joint filler has completely failed or is missing. Wheels go “thunk, thunk” every time they go over the joint. Productivity suffers, and the joint fills with dust and debris.
A popular and effective way to repair spalled contraction joints is to lock them back up with Roadware 10 Minute Concrete Mender™. Once the slab is 12 months old, the shrinkage and curling has finished. There is no longer a need for contraction joints. Now you can use Concrete Mender™ and silica sand to bond the slab back together from the base all the way up to
the top. This will stabilize the slab, restore aggregate interlock,
and allow for complete and even load transfer from the wheels all the way down to the base. Your contraction joint problems are solved.
NOTES: Locking up contraction joints
is recommended for interior controlled environment applications with sound concrete and base. Exterior applications may have different results. Always test a small section
of large repair for compatibility.
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.
UPDATE:
September, 2013
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.
