Remove loose material and create a shelf on both sides of the joint with a minimum profile of 1.5” deep and 2” wide on each side. Vacuum and thoroughly remove dust and contaminates.
Create a repair base by filling repair area halfway to grade with bulk mixed 10 Minute Concrete Mender™ combined with 10-20 grit silica sand.
Use a ratio of 1 Part mixed Concrete Mender to 2 parts silica sand. Up to 1/2 part additional sand may be added during application to assist with troweling and placement. Be sure to leave the lower half surface rough and sand covered to accept the next layer.
EXAMPLE
1 Qt side A,
1 Qt Side B,
4 Qts 10-20 silica sand,
Up to 1 quart additional sand as needed.
Once the first layer sets and turns grey, continue with an additional layer up to flush with the surface.
The mixed material should always be resin rich and the sand should be fully saturated when applying to the repair area.
For extra surface strength, 30 grit aluminum oxide may be broadcast and troweled in place on top as the materials start to gel in about 5 minutes after placement. Allow to fully cure and grind flush within 24 hours. OPTIONAL: Re-saw the contraction join
A new freezer floor coating developed by Roadware, Inc. can stop concrete dusting and restore freezer warehouse floors. Concrete dusting in your warehouse floor is a difficult challenge. Dusting is when the concrete surface deteriorates to powder due to heavy traffic, improper placement of the original concrete, mix design failure or a number of other reasons. Surface dusting can lead to hazardous conditions for personnel, unsanitary conditions and product contamination. If the concrete is solid beneath the surface, these slabs can be made serviceable with specialized coatings. Coating slabs like this is even more challenging in a working freezer where temperatures are typically -20 degrees F (-29C).
Dusting concrete floors in a freezer can lead to unsafe and unsanitary conditions as well as contamination of product.
Concrete dusting can lead to the complete breakdown of the concrete wearing surface. Pallet jacks and forklifts can grind down the concrete allowing silica dust to become airborne and causing a health hazard.
Freezer warehouse floor with failed topping slab and dusting concrete.
Disbonded topping slabs and epoxy coatings can also create a hazardous dusting situation.
Freezer floor being prepared for coating with Roadware Freezer Coating by grinding the surface flat with metal grinding pads.
Here concrete polishing equipment with metal grinding pads are used to remove the dusting surface of the concrete back to a solid surface.
Freezer floor being prepared for coating with Roadware Freezer Coating by grinding the surface flat with metal grinding pads.
Hand grinders can also be used to remove the dusting surface. Dust collection systems are used to collect hazardous silica dust.
Roadware Freezer Floor Coating is easily mixed in a pail using a ratio of 1 part ISO, 1 part POLY and 1 part manufactured sand.
Roadware Freezer Floor Coating is mixed at a ratio of 1:1:1:
One quart A
One quart B
One quart 4030 grit silica or manufactured quartz sand.
Combined on a pail and mix with a paint stick or 10 seconds. Apply immediately.
Coverage rate shown here is approximately 2.5 Meters Sq per mixed liter.
Keep materials at outside the freezer at about 60-70 degrees before mixing. Floor and air temperatures in the freezer for this project were -4 degrees F (-20C).
Craftsman trowel down a thin sealer coat of Roadware Freezer Floor Coating on to a prepared concrete floor at below freezing temperatures.
A single trowel down application is all it takes to provide a new surface to the concrete and good working floor. Product is applied at freezer operating temperatures. Product cures in several hours depending on the temperature and odor is very slight. Stand-up trowels may be used as well.
See craftsmen with Concrete Dr in Seoul, Korea apply Roadware Freezer Floor Coating at -4 degrees F (-20C) . A propane torch is used to remove flash frost just before application.
Freezer warehouse floor coated with Roadware Freezer Floor Coating.
Full warehouse traffic can resume in 10 hours after application.
Freezer floor coated with the Roadware Concrete Mender Freezer Coating System. This resilient coating can be applied at freezer operational temperatures and cures within hours.
Floors treated with Roadweare Freezer Floor Coating are resilient and serviceable once again.
Product: Roadware Freezer Floor Coating
Features:
Low Viscosity
Easy Mixing
Fast Curing in sub zero applications
Very low odor
Very low VOC’s that polymerize into the material.
Benefits:
Freezer floors can be repaired or coated while operating.
Can be applied in odor sensitive areas.
Easy trowel down application.
Warehouse traffic can resume in 12-24 hours depending on temperature.
Uses:
Coating freezer floors to reduce dusting and improve riding surface.
Repairing cracks, joints, and spalls in freezers.
Limitations:
Products cures a translucent natural amber. Dry colored pigments may be added to the final mixing process if needed.
Surface must be, clean, dry and free of frost.
Frost and moisture must be removed with a propane torch or electric heated air just before application.
Excess moisture can cause the product to whiten in high moisture areas and will cause an inconsistent look.
Roadware Freezer Floor Coating is available on a special order basis at this time. Call 800-52-7623 for more information.
Kelton Glewwe is Vice-President of Marketing for Roadware Incorporated and an original founding partner of the company. Kelton has set up sales and distribution networks for Roadware construction products in over twenty countries around the world. He has worked on projects ranging from automated freezer warehouses in Washington to 100 year old railroad piers in New York and Airport Runways in Hong Kong. Kelton is a graduate of the University of Saint Thomas and lives in Inver Grove Heights, Minnesota.
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 is a proud member of the International Concrete Repair Institute.
Here is the Roadware Concrete Mender One Page Pitch. Things you need to know when considering, recommending, specifying, and using Roadware 10 Minute Concrete Mender™
Full depth crack repair in warehouse floors usually involves cutting open the cracks with dry diamond saws. This is a slow process and creates a lot of hazardous silica dust that needs to be mitigated. Repair contractors at an Amazon Warehouse project are using an innovative way to repair cracks in the floor without the traditional cut and fill methods.
The problem:
Some people question why these types of cracks should be repaired. Cracked floors in industrial and commercial settings are a liability. The cracks will continue to get larger as wheeled traffic starts to crush the sidewalls. (More) Cracks will also fill with dirt and debris creating a hard to clean surface. Roadware 10 Minute Concrete Mender™ is a structural polyurethane that will restore load transfer and can bring a floor back to original serviceability.
This three level Amazon Warehouse developed thousands of linear feet of shrinkage cracks prior to being places into service. Roadware 10 Minute Concrete Mender will be used to repair them.
This floor presented thousands of feet of shrinkage and stress cracking. The cracks were all fairly clean without excessive foreign debris or dirt at time of repair.
The Plan:
Use sacrificial vinyl weatherstrip to make a dam parallel to the cracks that will hold Roadware 10 Minute Concrete Mender™ in place while it soaks down into the cracks. Concrete Mender™ is nearly water thin when mixed and will flow easily deep into open cracks. Since Concrete Mender™ will start to gel up in 5-7 minutes, it will naturally self-seal the bottom of the crack as it cures. It sometimes takes three of four light pours of material, but it will fill the crack completely and start the structural Microdoweling™ process. Microdoweling™ is how Concrete Mender™ uses low surface tension and molecular attraction to penetrate concrete surfaces and locking into the aggregate and rock matrix.
No-cut crack repair with Roadware 10 Minute Concrete Mender™ uses removable peel-and -stick weatherstrip to form a temporary well that holds the Concrete Mender in place while it soaks down into the crack.
Roadware 10 Minute Concrete Mender injected deep into cracks using the Roadware Easy Injection System.
Wehtherstrip is used to hold Roadware 10 Minute Concrete Mender in place while it soaks deep into cracks.
Application:
With Concrete Mender™, expensive pumps and equipment is not needed. Once cracks are vacuumed and the surface is cleaned. The weatherstrip dam can be applied. Roadware 10 Minute Concrete Mender™ can be mixed on one gallon batches by hand in a bucket and poured directly into the cracks. Additional manufactured sand can be added for larger cracks, but it is not recommended for this type of repair. See more here: Concrete Mender Bulk Application Instructions
Pour equal parts A and b into a mixing container and mix for about 15 seconds with a mixing stick.
Crack repairs are filled with Roadware 10 Minute Concrete Mender to refusal and the excess is removed.
When the Concrete Mender™ cures in about 10 Minutes at 72 degrees F (21C) , the weather stripping and excess material can be shaved clear or ground smooth with standard equipment.
Roadware 10 Minute Concrete Mender filles hairline cracks completely using the dam and flood method. No cutting is needed.
After buffing and clearing excess material, floors can be returned to service immediately.
Finished concrete crack repair blend in nicely at an Amazon warehouse using full depth Roadware 10 Minute Concrete Mender™.
Additional buffing and service traffic will blend the repairs even more into the surrounding concrete.
Roadware 10 Minute Concrete Mender Technical Data Sheet
Roadware stands ready to supply immediate concrete repair needs for warehouses, cold chain logistics, manufacturing, and supply. Repairs can be made with almost no downtime and under operational conditions. Please call 1-800-522-7623 or 1-651-457-6122 to be connected with our worldwide network of distributors waiting to assist. Or, send email to sales@concretemender.com
We ask that visitors to Roadware Headquarters in South St Paul, MN, or any of our Roadware Distributors, call the location ahead to verify operating hours and local conditions.
AGV’s or Automated Guided Vehicles are the reliable workhorses of the modern warehouse. They are designed to run smoothly and predictably all day and everyday. AGV’s are great at repetitive tasks moving freight as needed day in and day out. These repeated trips over the same path can be very punishing to concrete floors. The small hard wheels of an AVG can crush control joint sidewalls and grind the concrete surface to dust. This leads to rough, uneven floors that can cause premature breakdowns of AGV drive systems, wheels, and even damaged freight.
“If your AVG could talk, it would ask for Concrete Mender. ” Richard King, Roadware, Inc.
AGV’s move thousands of pounds in a single trip over the exact same path hundreds of times per day.
Roadware 10 Minute Concrete Mender with Microdoweling™ penetrates into concrete surfaces repairs concrete cracks, joints and spalls where others fail. Over the years we have noticed some conditions needed for successful repairs in the path of AVG’s.
Repairs need to be as tough as the concrete itself. But not too tough. Let’s say your concrete is a typical 4000 psi in compressive strength. The AGV wheels are grinding away the surface of the concrete and spalling the control joints. You repair the “bad” sections of the path with fairly brittle 10,000 psi epoxy. Now you have sections of the original concrete and sections of much harder epoxy. As the original concrete continues to grind away, the hard epoxy remains and you just created more speed bumps for the AVGs. Concrete Mender will wear with the concrete and deflect with the concrete under load. Your AVG’s favorite path will be smoother longer.
Stop your repairs from popping out. Did you ever notice common warehouse floor repairs popping out in chunks? This can happen when you put a super hard epoxy patch in a not as hard concrete floor. The epoxy is so brittle that it fractures the bond-line when a load is applied. Epoxy repair products have a modulus of elasticity that is so high, it will fracture the concrete before deflecting under load. Concrete Mender has a modulus of elasticity that is slightly less than concrete so it will deflect with concrete concrete under load and gently transfer load from the repair to the surrounding concrete.
Time is money! Closing down aisles or sections of a warehouse is a disruption for everyone including AVG’s. With minimal prep requirements and less invasive techniques including Roadware Easy Injection, 10 Minute Concrete Mender can have your AVG pathways back in service in minutes, not hours or days. You can even make repairs in operational freezers down to -30F.
Concrete repairs for AGV’s need to bond under heavy traffic as well as deflect with the concrete and transfer loads to the surrounding concrete without fracturing.
AVG’s like to take the same path every time. This can prematurely wear out concrete floors. The drive system in a typical AGV can haul a lot of weight, but the floor needs to be smooth. Warehouse and AGV floors can be repaired and open for traffic in about 10 minutes after application with Roadware 10 Minute Concrete Mender.
Two post automotive hoists and lifts are generally bolted to the floor using compression anchors. When the lift needs to be replaced, the new anchors can not interfere with the old anchor points. If the old anchor points are too close to the new anchor points, the concrete needs to be replaced before the new lift can be installed. This can close a service bay for a month or more.
With Roadware 10 Minute Concrete Mender, we can remove the old compression anchors, repair the concrete and install new compression anchors without having to replace the concrete.
Automotive lift floor attachment patten over existing list installation.
After removing the old lift, the compression anchors need to be removed. If the original anchor hole was drilled full depth, they can be driven down beneath the floor with a hammer and a punch. If the anchor are not full depth, a core drill is used to remove the anchor.
Using a 2″ core drill to remove existing anchors.
After drilling, the holes are cleaned and reamed with a reaming bit to roughen up the sidewalls. A shop-vacuum is used to remove all dust and debris. The concrete is than cleaned with alcohol or a similar evaporating cleaner. The holes have to be clean and completely dry before proceeding.
Core drilled anchor holes are cleaned and roughened with a hole reamer.
Use duct tape to mask off the holes to be filled with Roadware 10 Minute Concrete Mender™
Masking off the old anchor holes in preparation for repairing with Roadware 10 Minute Concrete Mender.
Gather the materials needed to repair the holes. Roadware 10 Minute Concrete Mender is designed to repair cracks, spalls and holes in concrete. Not just simply fill them. The Microdoweling™ penetration of Concrete Mender into the concrete is a structural repair and can bring the concrete back to original design parameters.
Items needed:
80020 Two-gallon kit of Roadware 10 Minute Concrete Mender.
4030 grit or similar dry manufactured sand or quartz. Enough to fill the holes.
Mixing and measuring pails. One quart paint mixing pails work well.
We made a short video to demonstrate the basic technique of filling a core drilled hole in concrete. Concrete Mender doubles in volume when adding sand. All we need to do is fill the hole halfway with Concrete Mender and then add sand to bring it up to the top. Note: In the field it may be impractical to get the bottom of the hole completely dry or clean especially if the hole is full depth into the base material. Simply repair the bottom 1/4 of the hole with Concrete Mender and sand first and allow it to cure before repairing the rest of the hole up to the top.
Measure out equal parts of Side A and Side B Concrete Mender and combine them into your mixing bucket. Mix with a stick by hand for about 15 seconds.
Pour equal parts A and b into a mixing container and mix for about 15 seconds with a mixing stick.
Mix equal parts Side A and Side B by hand in a mixing pail for 15 seconds.
Fill the holes half-way with mixed Roadware 10 Minute Concrete Mender.
Fill the hole halfway with mixed Concrete Mender. Use a marked stick to gage the halfway mark.
Add sand into the hole bringing the Concrete Mender level up to the surface. Make sure all the sand is completely saturated.
Pour sand into the hole bringing the Concrete Mender up to the surface.
Level the surface with a trowel or stick and allow to cure for about 10 minutes at 70 degrees F (21C).
Smooth the top of the repairs with a trowel or mixing stick.
Remove the tape after the Concrete Mender cures and turns grey in about 10-15 minutes.
Concrete Mender turns grey when it cures. Pull the tape.
A finishing rubbing brick is used to quickly bring the repairs flush with the floor.
Concrete Mender repairs are made flush with a rubbing brick.
Holes to anchor the new lift are marked and drilled into the concrete. Time to test the repairs and make sure the repairs will hold the anchors for the new lift.
New anchor holes are drilled for the new lift next to the repaired holes from the old lift anchors.
New compression anchors are installed and torqued to the specified level.
New compression anchors and installed.
For the repair to be successful, the compression anchor must hold 3000 lbs or 1360 kg for 12 hours without cracking or splitting of the surrounding concrete.
An anchor testing device is used to pull 3000 lbs of force on the anchor for 12 hours.
Compression anchor testing device showing 3000 pounds of force.
Several anchor were tested. All passed and the lift was installed the next day and placed into service. Roadware 10 Minute Concrete Mender™ is designed to bring most concrete slabs back to original design strength. Repairing anchor holes prior to new automotive lift installation with Roadware 10 Minute Concrete Mender is now the specified choice for two of the largest auto service companies in the United States.
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.
Scoring a concrete crack with a diamond grinder.
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:
Delivery of materials to the repair area.
The repair material needs to set before if flows away from the repair area .
The repair has to be structurally effective.
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.
Diagram showing Concrete Mender Soft-tip mixer injection into a concrete slab.
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.
Roadware 10 Minute Concrete Mender with Easy-injection mixer repairing a hairline crack.
Concrete Mender crack injection into 24 inches of concrete. Notice the material penetrating full depth.
Hairline cracks less than 20 mil across repaired using Roadware 10 Minute Concrete Mender and Easy Injection application. UV Forensic Photography. See More Here
