Alchatek Blog

In this blog post, we will share some tips for stabilizing soil in cold weather. The two main points to remember are – make sure the ground isn’t frozen and condition your material and equipment properly.

Do Not Attempt Soil Stabilization Work When the Ground is Frozen

If you’re considering soil stabilization in cold weather, the first step is to make sure that the water table isn’t frozen. Iced earth is not permeable enough for proper mixing of resin and soil. If you attempt to proceed with frozen soil, you’ll just be wasting your material. Best to wait it out in that case.

Properly Condition Equipment and Materials

For optimal results, it’s best to store any materials and equipment that are to be used in a heated environment over night. It’s best to keep your AP Soil 600 above 60 degrees at all times. This is key because cold material reacts slower and gets thicker. The methods you use to condition your material on the job site will depend on the type of vehicle you’re using.

In Slab Lifting in Cold Weather, we described in detail how to condition materials for cold weather if you’re using a rig…

If you have an insulated rig, it should stay around 40 degrees warmer than outside temperatures. Most foam rigs have built in electric heaters that require an extension cord to a power outlet at the job site or at your facility for overnight storage. Alternately, you could buy an electric radiator heater. Other available heating devices include drum band heaters and heated drum mats (be careful not to scorch the polymers by turning band heaters up too high). For a more DIY approach, you could build a hot box around the material storage area in your rig.

If you’re using pails and a smaller vehicle, we offered tips for that set up in my Polyurethane Leak Seal in Cold Weather article…

Use an enclosed vehicle, like a box truck, enclosed trailer or pickup truck with a camper top or bed cover. Keep as much material and equipment inside the vehicle as possible when working. Use a portable heater to maintain a warm temperature. You can also use electric pail heaters to keep your resin ready for action.

Using a combination of the methods described above, you should be able to keep your materials warm enough. In extreme cases when the material gets a bit too cold and thick, you may want to use AP Cat 600 to speed up the reaction time.

Conclusion

As long as the ground isn’t frozen, you should be able to stabilize soil in cold weather.  Just make sure your materials and equipment are conditioned properly.  If you have any further questions, please contact us at 404-618-0438.

Want in-depth info on soil stabilization products?

As we stated in a previous blog post, Slab Lifting in Cold Weather, there are plenty of jobs that need to be done in the winter. This is just as true for sealing leaks as it is for slab lifting. So let's take a look at those cold weather leak seal markets. We'll also review some special considerations for conditioning leak seal material and equipment. Then we’ll leave you with a few cold temperature leak seal application tips.

Cold Weather Markets

You have a variety of options for seeking jobs that are inside, out of the elements, during the winter months.  Hopefully these ideas will spark more brainstorming on your part. First up we have tunnels, both pedestrian and vehicle. Tunnels often leak, sometimes significantly enough to result in quite a big job. Aquariums are another possibility. As you can imagine, there are infinite potential leak problems in a structure holding that much water. Other possible large jobs could include mines and water treatment plants (which have plenty of interior spaces with potential leak issues). On the smaller side, there are utility vaults, lift stations, manholes and elevator pits.

If you’re still up for working outside during the winter months, you’re in luck because concrete contracts during colder weather. The contraction makes cracks open wider. Wider cracks make leaks more apparent to the property owner and make them easier to repair.

Conditioning Materials and Equipment

One important point to understand is that cold weather requires you to make an extra effort to keep your materials and equipment warm. Cold material reacts slower and gets thicker. Be sure to store your materials and equipment in a heated room the night before the job. When on the jobsite, there are many ways to keep everything warm. Use an enclosed vehicle, like a box truck, enclosed trailer or pickup truck with a camper top or bed cover. Keep as much material and equipment inside the vehicle as possible when working. Use a portable heater to maintain a warm temperature. You can also use electric pail heaters to keep your resin ready for action.

Remember that it won’t do you any good to heat the resin if you’re pumping it through cold equipment. The cold steel inside the pump and the cold hose will literally suck the heat out of the resin before it gets where it needs to be. This will increase the viscosity, making it harder to mix with the water and it will slow down the reaction dramatically. So don’t neglect the equipment side of the equation!

Cold Temperature Application Tips

If you’re using a product with an accelerator, you may need to use a faster accelerator or increase your percentage. Also, bring lots of oakum. You may have to use more if the cold temperature slows down the material or the contracted concrete has made the cracks wider.

If your job requires you to inject into a structure underwater (and the water’s cold), you can use a technique called twin streaming. In this approach, you hook two valves together in parallel fashion – then inject warm water along with the resin to kick start it reacting before hitting the cold water.

Conclusion

I hope this overview has helped spark some ideas on your part for finding leak seal work during the winter months. Just remember to keep your materials and equipment conditioned and you should be fine. Have more questions about polyurethane leak seal in cold weather? Call us at 404-618-0438.

Want more in-depth info on polyurethane leak seal?

Voids beneath concrete slabs can be filled with two component polymer foam designed to work in wet or dry conditions. AP Lift 430 foam can support up to 7,200 lbs per square foot and will cure to 90% full strength in 15 minutes.  (Of the most resilient concrete slab jacking foams, AP Lift 430 is proven to lift concrete slabs under harsh conditions. This two-component, high-strength, high-density, hydro-insensitive structural polyurethane foam is the top slab jacking solution for concrete slab foundation repair, soil stabilization, and compaction grouting. AP Lift 430 weighs 2.75 – 3.25 pounds per cubic foot.)

Polyurethane foam under concrete conforms to void shape more accurately than cement grout, and - unlike cement - it doesn't shrink or sink over time.

The video below depicts a real time example of void fill and slab stabilization. A residential driveway is undermined by a large void. Because an entire bank of soil washed away on one side of the slab, we get an unusually clear view of polyurethane void fill in action. 

Observe the process closely and let us know if you have any follow up questions. We have the most knowledgeable and helpful customer support in the industry, so don't hesitate to call us at 404-618-0438 after you've watched this video! 

Want in-depth info on slab lifting and slab void fill with polyurethane foam?

One of the hidden dangers a warehouse or industrial property owner and their employees can face is an unstable or sunken slab with a large void underneath.  The last thing anyone wants is injury and/or a lawsuit resulting from an un-repaired trip hazard or worse - a complete slab collapse.  Take a good long look at the photo in today's blog graphic.  This occurred when a forklift carrying a heavy piece of equipment crossed a slab with an un-detected void underneath.  Luckily, no one was injured.

This video below depicts (via an inexpensive borescope lowered through a drill hole) a real time example of a warehouse slab with cavernous voids below and heavy equipment resting on top.  Next, you'll see the slab repair process in action as the voids are filled and the slabs are restored to a safe, stable state with AP Lift foams that support between 7,200 - 14,000 pounds per square foot (depending on the product selected). 

Watch the process closely and contact us if you have any questions!

Want in-depth info on warehouse & industrial slab repair with polyurethane?

Just outside Saskatoon, Saskatchewan is a 12,000 square foot cement manufacturing plant that was being re-purposed for use as an agricultural seed sorting facility.  Built in the 1960s, the plant’s 10” thick, double rebar, 8000 psi concrete floors had settled.  An undetected broken water main on an adjoining property had been pumping thousands of gallons into the soil for years causing the floors to become independent of the footings which had sunk as much as 7 inches.  The new owner’s plan to demo the slabs – including some as large as 52 feet by 25 feet – and replace them came to a screeching halt when they proved to be too tough for even a track hoe mounted jackhammer.  All of the high tech seed sorting equipment was still sitting on pallets and couldn’t be installed until the floor problem was resolved.  With harvest season fast approaching, a mudjacker was hired to lift the slabs with cement grout.  This effort proved unsuccessful in that the final levels were not accurate enough, leaving the property owner in dire circumstances.

Powerful Polymer

Among the most dependable products for leveling concrete slabs, AP Lift 440, provides an exceptional DOT grade solution for these types of situations. This 4 lb. density, high-strength, hydro-insensitive structural polyurethane foam is perfect for lifting and supporting heavy concrete floors that have settled due to water infiltration.

Painless Procedure

An Alchemy-Spetec certified contractor lifted 5 slabs and fine-tuned 3 others that the mudjackers had unsuccessfully attempted with cement grout.  Overall, nearly 900,000 pounds of sunken slab were lifted with only twelve 100 gallon sets of 440; all in less than a week.

Rapid Result

The level of precision achieved with polymer foam was not only far greater than anything the mudjackers were able to deliver, but the rapid results allowed for the heavy seed sorting equipment to be installed on stable floors just in time for the fall harvest.  The floors are still perfectly level to this day.

Want more in-depth info on polyurethane concrete leveling?

Nowhere on earth are they building more railroad lines than in the People’s Republic of China. The most populous nation in the world is developing rapidly and with it comes a need for more and more freight and passenger rail - and the demand for higher and higher speeds. Unfortunately, these high speeds cannot be achieved on rail that is sinking and settling in various places, especially in tunnels. This slows down people and commerce and is also a concern for safety. The culprit is groundwater, soil consolidation, and in some cases poor compaction. This is the type of environment where AP Lift 475 has done some of its best work.

Powerful Polymer

AP Lift 475 is a two component, hydrophobic, structural lifting polymer designed for airport, highway, and railroad applications. It can be used to stabilize structures, fill voids, and lift slabs supporting tremendous loads. The real beauty of it is the ability to be traffic ready for a train or a jumbo jet in less than one hour. A few years ago, it was put to the test in tunnels in the mountains of China.

Painless Procedure

With rails sitting on double concrete slabs (the top slab was 1 meter thick, the bottom 30 cm) a plan was developed to bring the low spots back into tolerance by injecting AP Lift 475 underneath both slabs through extra-long injection packers.

Monitoring with laser levels, the low spots in the rail were lifted back to the original grade. AP Lift 475 performed as advertised. The railroad track was raised and supported, while at the same time the ground water was displaced, literally jetting out of relief holes as it sought a place to escape.

Rapid Result

Working in 4 hour windows where the rail traffic is shut down at night, crews lifted low spots in these tunnels quickly and efficiently.  At 5 AM equipment and personnel had to be clear of the tracks and 15 minutes later the trains would rumble through.  Vibration monitoring by railway engineers showed a smoother ride and the people and commerce of China were allowed to move once again at a frenetic pace.

Want More In-Depth Info on Concrete Leveling Polyjacking Products?

County inspectors found a depression in the road due to an underground sewer line that wasn’t sealed at a heavily trafficked roadway intersection in Orange County, Florida.  Water and eroding soil were infiltrating the sewer line causing the road to slowly settle.  The resulting voids around the drainage structures had the potential to grow larger, eventually resulting in a complete cave-in of the roadway.  In this particular case, there was a patch of asphalt 12’ x 25’ that was settling and officials feared a cave-in would occur.  A point repair was done from within the leaky pipe to stop the infiltration but they feared it was only a matter of time before the road gave way. It was going to be very difficult and inconvenient to dig up this roadway, fill the void, re-compact, and re-pave due to the high volume of traffic, the adjoining rail crossing, as well as several major utilities running through the area.  Not to mention that the area would have to be completely shut down to accommodate all of the equipment required for such a repair.

Powerful Polymer

Orange County approached us to see if we could come up with a powerful, painless and rapid solution for their maintenance crew using chemical grouting to fill the voids and stabilize the roadway. We devised a solution for them using the versatility of AP Fill 700 as both a permeation and void filling grout.

Painless Procedure

We advised their crew to lay out a grid on the settling asphalt area and set up injection points to drive pipes down to the 13’ depth where leaking had occurred and where the loose soil zone was located. They monitored the pipes while injecting material at a rate of 2 gallons per vertical foot through the open manhole to identify additional leaks that had been missed during the first point repair. As expected when foam was observed coming in through a leaking joint it quickly sealed off the leak at the same time it was stabilizing the soil.

Rapid Result

To keep the lane closure down to a bare minimum of time, the project was successfully completed on two separate Saturdays.  The voids were filled, the loose soil was solidified, and only minor asphalt patching was required to make that area smooth for traffic again.

Want in-depth info on soil stabilization products?

On top of a hill northeast of Chattanooga, Tennessee sits a clearwell that belongs to Eastside Utilities. Built in the 1940’s on a former Army post, this clearwell consists of twin 2-million gallon tanks used for treating surface water to turn it into drinking water. The problem was that less than half of the water coming into the clearwells was making it out the other side. Although this water treatment plant has undergone several upgrades in its 70+ year lifespan, the ground beneath it has been subject to settling and consolidation. The tanks had shifted slightly and in doing so, loosened some of the joints and the water stops contained within. Measurements indicated that the clearwells were losing 1,700 gallons per minute through various leaks; well over 2-million gallons per day. A short drive downhill from the property revealed various gullies and small creeks created by water running down the hillside.

Powerful Polymer

An Alchemy-Spetec certified installer was called in to utilize Spetec PUR GT500, an NSF /ANSI 61 approved product for contact with drinking water, to seal the leaks.  This single component polyurethane resin is designed to penetrate and seal off leaks in cracks, joints, and pipe penetrations.  As a hydrophilic polyurethane, it chases down water and gets into the microstructure of the concrete, forming a flexible seal and a tenacious bond with the wet concrete.

Painless Procedure

Due to the amount of water escaping, all of the joints around the perimeter walls were suspect as well as the roof support columns throughout each clearwell that penetrated through the floor.  The contractor drilled holes to intersect the leaking joints around the perimeter of the clearwell and along all interior joints.  Injection ports were installed and Spetec PUR GT500 was pumped into each one to create an injected membrane within the joints and beneath the clearwell.

Rapid Result

After three days of injection the work was done and the site was cleaned up.  Monitoring after the Spetec PUR GT500 was installed indicated that the leak had been reduced from 1,700 gallons per minute to 10 gallons per minute.  The small number of remaining leaks were attributed to the many vintage valves and fittings that are still present at the plant.

Want in-depth info on polyurethane leak seal injection?

In our continuous effort to make sure you have the technical knowledge to succeed, we’ll explain how to select the appropriate slab lifting polyurethane.

Use the Right Supplier

First and foremost, you want to be sure you’re working with the right supplier.  For niche work like polyurethane slab lifting, you need a company that specializes in polymer concrete repair materials.  Some larger polyurethane manufacturers make everything under the sun in addition to lifting foam, such as mattress foam, carpet padding foam, etc.  Your materials would be manufactured quarterly at most.  Technical support, if it exists, is unfocused and lacking in detailed expertise.  Don’t set yourself up for failure by going this route.

The right supplier will be a specialized polymer manufacturer with a laser-like focus on producing the best slab lifting foam possible.  Even better, they should offer dedicated tech support from professionals with field experience on actual slab lifting jobs.  Set yourself up for success with the absolute best supplier partner you can find.

If a Specification Exists, Read it!

If you’re working on a larger job involving an engineering firm, make sure you read the specs!  (If the Department of Transportation is involved, they will also have one available.)  For experienced contractors, this is just basic common sense obviously.

Foam for Filling Voids

An empty void underneath a slab needs to be filled with a lighter density foam that has an excellent expansion rate yet still ahs the structural strength for the application.

Different Foams for Different Lifting Jobs

The foam you choose for lifting will depend greatly on the size of the slab and the amount of weight it typically bears.

• Residential Jobs
  Driveways, walkways, garage floors and the like can usually be lifted with 3 lb density foam such as AP Lift 430.

• Common Commercial/Industrial Jobs
  Warehouse floors, concrete retail floors, larger concrete parking slabs and the like will require 4 lb density foam such as AP Lift 440.

• Maximum Weight Bearing Slabs
  Airport runways, railroad slabs, transformer pads, factory floors with heavy equipment, grain silo slabs and the like will require 4.75 density foam such as AP Lift 475.
  

Foam Designed for Wet Environments is Essential

At LEAST 90% of the time, water is the underlying cause of slab problems.  On most jobs, the soil will contain at least some infiltration.  So ALWAYS make sure your foam is designed for environments with moisture in the soil.  Many companies offer resins that will NOT work in wet environments or will require a lot more material to get the job done.  Why pay good money for a product that won’t work 90% of the time?  Every Alchemy-Spetec lifting foam is designed to work in wet environments.

NSF Approval is a Must

NSF approval is ESSENTIAL for doing work near waterfronts, food processing operations, water treatment plants, etc. 

This single designation ensures compliance with the Safe Water Drinking Act (SDWA) and guarantees peace of mind for in-the-field stakeholders on construction projects of almost any scope and size.

The SDWA gives the EPA latitude to impose criminal and civil penalties on industries not in compliance. In 2014 enforcement efforts policing clean water netted $163 million in penalties and fines, 155 combined years of incarceration for sentenced defendants, and $16 million in court-ordered project clean-ups.

Contractors and engineers must be able to confidently choose vendors whose products and services won’t become the source or cause of drinking water contamination.

Alchemy-Spetec is one of only TWO companies in the world with NSF approved lifting foam.

We’ve Got Your Back

If you’re still not sure what the right choice is for an upcoming job, then not to worry – we’re here for you!  Our staff has the expertise both in the lab and in the field.  We can help you make the right decision.  Just give us a call!

Want in-depth info on slab lifting polyurethane and procedures?

Reminder!  Book your personalized meeting with an Alchemy-Spetec rep at World of Concrete!

Alchemy-Spetec will be at World of Concrete 2019!  Drop by to see us at Booth # O40551 in the Silver Lots (same location we were in last year).

There will be a LOT to see and do at our booth this year: 

• See the Polybadger Lifting System in action. 
• Learn about preventative waterstop products. 
• Get in-depth instruction on using and cleaning the MixMaster Pro slab lifting gun. 
• View leak seal and curtain grouting displays. 
• Mix foam samples at our live mixing station. 
• Learn about the Deep Lift process. 
• Tour a fully stocked slab lifting rig (you can even take it home with you if you're ready to buy!)

Respecting YOUR time is important to us.  So, in addition to the action-packed list above, you can schedule a one-on-one consultation with your regional rep for personalized product or equipment demos, tips and advice on building your business, etc.

Want a personlized one-on-one meeting at World of Concrete?