Epoxy Injection of Structures Part 3

February 24, 2017

This is the third in a series on Infrastructure Repairs Using Epoxy. Part One is  Introduction to Epoxy Injection.  Part 2 is Crack Analysis Before Epoxy Injection

If your have not read that yet you may want to go back and read it before you proceed with reading this.

Port Setting

It is extremely important that if drilling to use the right tool. to set drill type ports use a vacuum swivel drill. That is a drill with vacuum attached swivel drill chuck and hollow a drill bit.

Concrete dust can be detrimental to the injection processes in several ways. Any dust remaining in the drill hole near a crack can combine with the very low viscosity injection resin. This thickens your resin turning it into a weak paste. This paste can slow or even block the resin flow. Drilling very tight crack with a solid drill forces dust into the crack. This seals the crack from resin flow. Do not allow shortcuts in the drilling procedures!  However, for most applications the surface port is the easiest and most effective method.Epoxy Injection Surface Port

Port Spacing

Determining the spacing of ports is done by a highly experience applicator. This spacing is a factor of the tightness of the crack and the depth of the concrete substrate. Spacing is normally between four (4) and eight (8) inches.

Port Setting and Sealing

Align ports directly over cracks. That allows injection resin to flow into the crack. Seal surface cracks. Sealing the exterior of cracks is done with Epoxy Gel type Bonder.

Testing The System

Test cracks that are ill defined, or if dust or debris is in the crack. This testing may be done by injecting water into the crack area.

Water left in the cracks will not effect the injection process or the curing of the Epoxy.com Injection Resin. Heavier injection resin forces the water out the cracks. Water injection helps clean the cracked areas. More important, is that it helps avoid the unexpected. This process of flushing the cracks is commonly skipped by more experience contractors, who can tell if there will be a flow of resin, by just looking at them. However, when in doubt water testing is a must.

If the cracks contain algae, chlorinated water containing copper sulfate is injected. After pumping this mixture is left over night. The next morning the crack is flushed by pumping fresh water, into it. This flushes it out before resin injection begins.

Efflorescence builds up on the bottom of a crack in a horizontal slab. Water in the crack extracting soluble calcium hydroxide is the cause. The water evaporates at the surface leaving the lime, which later reacts with the carbon dioxide in the air to form limestone. The inside of the crack, is frequently free of limestone and making it suitable for injection.

Part 4 of this series: Injection Resin Materials Product Selection.

For more information visit our website at http://www.epoxy.com, email us at info@epoxy.com or call our technical service department at +1 (352) 533-2167.

 


Epoxy River Simulation

November 16, 2016

How to Simulate a River Bed in Epoxy


A customer asks, “I recently saw what looks like a creek bed built out of epoxy with stones in it. How is this done in epoxy?”

Here are the steps to do it:

  1. Choose your stone. The stone that you choose can be uniform in size or a blend of stone sizes and shapes.  If bigger stone is going to be used, it is recommended that you use a blend of larger stone with smaller stone.  Variations in shape will also help to increase the amount of surface area holding the system together, making it stronger. Be sure the stone is clean and completely dry before attempting any of the steps below.
  2. Make a mock-up of the complete system below in a small box made out of plywood or similar material. This will verify everything from stone selection, to aesthetics, to stone durability. It is also gives you a chance to practice your procedure,and get additional phone tech support from us if required before you proceed with your project.
  3. Construct the recessed area that your river will “flow”. That could be a recessed area in a concrete floor, a wooded shadow box or some other “box” to hold your river. Be sure the box is watertight and that the surface is properly prepared before proceeding –www.epoxy.com/surfaceprep.aspx
  4. Prime the area created in step 3 with Epoxy.com Product #12 – www.epoxy.com/12.aspx at a rate of 250-300SF per gallon.  Allow to cure until hard to the touch, typically 6-8 hours
  5. After the Primer in Step 4 is hard to the touch and before 24 hours has passed, apply a coat of Epoxy.com Product #1 – http://www.epoxy.com/1.aspx – 100% solids General Purpose Epoxy Coating to the bottom of the box created in Step 3.  This will help to give you a consistent background color. Black helps give you the illusion of infinite depth.
    1. Optionally you can add a second coat of the #1 Pigmented Epoxy Coating to increase color intensity.
    2. On the other hand if the stone in Step 6 is so deep that you will not be able to see through it you can skip this step and proceed to step 6.
    3. Allow the epoxy in Step 5 to cure hard to the touch before proceeding, typically 10-12 hours.  Do not wait more than 24 hours before moving on to Step 6.
  6. Properly mix Epoxy.com Product #17 – www.epoxy.com/17.aspx – Epoxy Stone Adhesive Part A and Part B. Add your stone into the mixed stone adhesive.  The amount of stone that you will be able to add to it will vary depending on size and how clean the stone is.  100 lbs per 3 quart batch (2 QT “A” and 1 QT “B”) is a good starting point.  This ratio should be verified in a mockup before proceeding to this step. Mix in the stone until a uniform shine can be see on all the stone. Install this mix into your “box” at the desired thickness. Be sure to pack it in tightly and level to the desired surface.  Allow to harden overnight. Do not wait more than 24 hours before moving on to Step 7.
  7. Properly mix and pour Epoxy.com Product #214 – www.epoxy.com/214.aspx – Table Top and Casting Epoxy into the spaces between the rock in step 6. You typically will want to pour a minimum of 1/8 inch or not more than 1/2 inch at a time.  Take care to break any bubbles as you go early and often.  This is typically easy to do using a hair dryer and/or Isopropyl (rubbing alcohol mist). Allow each layer to harden and cool before adding another lift.  Never wait more than 24 hours in between coats and/or pours of epoxy.

When you complete this project it will look like a stone riverbed filled with \ water.  You can also experiment with other objects in your stone mix.  Contact Epoxy.com Technical Support with your questions: info@epoxy.com or 352-533-2167


Monument Repairs with Epoxy

March 9, 2016

A technician who uses a non-Epoxy.com product to repair tombstones wrote me recently looking for help with problems that he was having. He goes on to say that the epoxy that he uses never fails, but rather the stone fails. When a secondary break occurs, the stone always re-breaks about 2 mm (about ¾ inch) above or below the epoxy joint. The epoxy attached to about 2 mm of the stone and holds well.

He asked me if the epoxy shrinks so much that it will ‘ pull away ‘ from the stone it’s attached to, and in his case, it pulls about 2mm of stone with it.

No I doubt it is epoxy shrinkage causing the problem. High quality epoxy has little or no shrinkage. It would have to be a very poor quality epoxy to be shrinking enough to do that.

The reason his epoxy is not working is that it is too rigid. His existing rigid material has a “high modulus of elasticity”. A material with “high modulus of elasticity” is a material that is stiff and/or rigid. A “low modulus of elasticity” material is semi-flexible, and is not rigid or brittle.

T pieces of the stone structure (in this case a tombstone) and pieces not in touch with the ground tend to get hotter and cooler faster than the larger pieces and pieces with ground contact. This is called “differential timing of the event”. For example the top of a tombstone can be heated and cooled on 5 sides, the top and the 4 sides. The base of the tombstone which is buried in the ground has earth or stone on all of its surfaces. This earth and stone tends to keep the temperature of the base more stable by insulating it and slowing the change in temperature. This works much like the insulation in your house slows temperature changes inside your house.

When an object like a piece of stone is heated it expands (gets bigger). When an object cools it contracts (gets smaller). For example 100 feet of concrete will be 1 inch longer once it is heated 100 degrees F. That is why expansion joints are cut into concrete.

In the case of tombstones all the pieces of the same type of stone have very similar if not identical “coefficient of expansion”. Since the pieces are positioned with potentially different timing of heating and cooling there is a “differential timing of the event” (see above). The result is stress areas you are seeing in the closest weakened plane in the stone near the bond line.

Product #2005 was specifically designed for tombstone (monuments) and/or stone bonding, or repair. Epoxy.com Product #2005 is very strong yet it is has a “low modulus of elasticity” (semi-flexible). The low-modulus of elasticity helps to absorb differential movement (two sections of stone heating and cooling at different times), making it much less likely to cause a stress area in adjacent weakened planes.

Camouflage the bond line rubbing stone dust(ground off the original stone or a similar colored stone) into any exposed epoxy material while the epoxy is still “wet”. That way the dust will stick in the wet epoxy making the epoxy difficult to impossible to see.

Please send your additional question and blog ideas to norm@epoxy.com


Waterproofing of Leaking Foundations

May 4, 2015

This is the time of year when the ground thaws and basements leak. If you are one of those building owners, here are some earlier posts that you will find useful.

  1. https://news.epoxy.com/2014/09/04/epoxy-waterproof-block-wall-foundation/
  2. https://news.epoxy.com/2014/09/15/shows-how-to-identify-leaks-that-need-waterproofing-in-basement-walls-and-floors-that-are-made-out-of-poured-concrete-part-2b-will-deal-with-the-actual-repairs-to-poured-concrete-leaks/
  3. https://news.epoxy.com/2014/09/18/epoxy-injection-repairs-of-cracks-in-poured-concrete/

Poured Concrete Basement Waterproofing with Epoxy

September 18, 2014

This is the second half of a 2 part of a series on basement waterproofing with epoxy. In Part 1, we discussed waterproofing block wall foundations with epoxy. In Part 2A we discuss how to identify leaks that need waterproofing in basement walls, and floors that are made out of poured concrete. In this part (2B) will deal with epoxy injection repairs of cracks in poured concrete, that cause the leaks.

Earlier we discussed how many homes and businesses experience leaky basements year after year. The worse time is in the spring and after heavy rain. We discussed prudent things that you can do to improve drainage against your foundation. Epoxy Injection is designed to waterproof and give you the concrete’s structural integrity back.

Why Epoxy Inject the Cracks?

We discussed in our last article that cracking is a sign of failure caused by stresses, inadequate design, improper curing, etc. One of the dangers of a structural crack is the effect that it has on the reinforcing bar. The reinforcing represents one of the main structural values of the concrete. Cracks left unprepared allow water to enter your basement and attack the rebar.

Epoxy injection resin has two purposes:

  1. It effectively seals the crack to prevent the damaging moisture entry. Second, it monolithically welds the structure together.
  2. The injection also stops the infiltration of water into your basement.

Epoxy Injection Port Setting

Clean the concrete on both sides of the crack being careful not to force concrete dust into the crack. Concrete dust can be detrimental to the injection processes in several ways. Vacuum the area completely with a shop vac.

You need to determine the spacing of ports to be set. The spacing is a factor of the tightness of the crack and the depth of the concrete substrate. Spacing is normally between four (4) and eight (8) inches.

Port Setting and Sealing

Align ports directly over cracks. That allows injection resin to flow into the crack. Seal surface cracks and the ports in place. Sealing the exterior of cracks is done with Epoxy Gel #2006.

Selecting the Right Epoxy Injection Resin

Epoxy injection resin should typically be low viscosity injection resin- Epoxy Injection Resin #301. It must be low viscosity resin so it will flow in the smallest hair line cracks. Resin can travel several feet from the point of injection. It may take some time before reaching the next port or penetrating through pin holes in the surface. Epoxy injection effectively fills cracks including small voids and hairline cracks

Pumping Epoxy Injection Resin

The most economical way to deliver the epoxy injection is with the 450 ml binary injection system, a manual gun, or the pneumatically driven one. This uses a binary caulking gun with static mix tubes to inject the resin, insuring continuously mixed fresh material.

Limit pressure, low pressures allow gradual resin flow into the crack for deeper penetration. Start injection at the lowest point, and continues upward on the crack area. While injecting the lowest port, resin will flow to and out of the next higher port.

When pure resin is flowing out the next port cap, plug the current injection port and move to the next port. Then injection continues in the port showing resin flow. This procedure continues until all ports are full.

CONCLUSION

Epoxy injection is very effective at repairing concrete cracks and cutting of water infiltration. The right resin and equipment is critical. Epoxy injection makes a crack watertight while restoring the original structural integrity intended for the concrete. You can get all of the material you need to do this by contacting us:

321-206-1833 Customer Service – Ordering and Order Status
Katey Fontaine, VP – Customer Service Director
sales@epoxy.com

Technical Support
352-533-2167
Norm Lambert, President
Technical Support Director
info@epoxy.com

Additional Resources

http://www.epoxy.com/injection.aspx


Basement Waterproofing with Epoxy Part 2A

September 15, 2014

Poured Concrete Foundation Waterproofing

This is number 2A of a 2 part series on basement repairs. In Part 1, we discussed waterproofing block wall foundations. In Part 2A shows how to identify leaks that need waterproofing in basement walls, and floors that are made out of poured concrete. Part 2B will deal with the actual repairs to poured concrete leaks.

In our last piece we discussed how many homes and businesses experience leaky basements year after year. The worse time is in the spring after winter accumulation of snow. There are a number of prudent things that you can do to improve drainage against your foundation like roof gutters, grading and improvement of drainage. The recommendations here do not replace that conventional wisdom. It is designed to augment and improve upon these conventional methods.

Identifying the Source of the Basement Water Leak

The nice thing about poured concrete is that it holds water back very well. The leak typically happens at a cold joint or in a crack or hole in the concrete.

Concrete Cold Joints

Fresh (plastic) concrete doesn’t bond to hardened concrete. The exception is when a special epoxy bonding agent like Epoxy.com Product #2007 – is used (this bonding agent will be discussed in a future article). When concrete has hardened or has started to harden and you pour more concrete against it (without the right bonding agent) you get what is called a cold joint. These cold joints are a common source of water leaks.

Virtually all basements are built with a giant cold joint – the cold joint between the floor and the wall. Typically there is some sort of water-stops material installed in these joints intended to stop leaking at this cold joint. These water-stops can fail. So the wall to floor joint in a concrete basement is a frequent source of water leaks.

You can also get cold joints in the middle of concrete walls and floors due to multiple pours. You can get cold joints if concrete is setting to fast and fresh concrete is poured against semi cured concrete. Sometimes saw cuts in the floor can be a source of leaks

Form Ties

Then there are the ties that go through the concrete to hold the forms together on either side during the pour. If these form ties are not installed perfectly or if the concrete is not totally vibrated around them, these ties can act as a conduit to let the water in.

 

Wall and Floor Cracks

When concrete cures it shrinks that is called “plastic shrinkage”. That plastic shrinkage can and usually does result in the concrete cracking. These cracks are one of the easiest ways for water to get into your basement. If the water makes it to the fill side of the tank (under the floor or against the wall) it will typically leak out into your basement. You should look carefully for these cracks when looking for potential leaks into your basement. If you are able to investigate into the water infiltration into your basement when it is leaking it will be easy to see. If trying to find the source of leaks when the basement is dry you have to look for water marks on either side of the cracks and beneath the areas that might be leaking.

Repairing the Basement Leaks with Epoxy

In the next installment on this topic, I will deal with how you waterproof the cracks while structurally repairing them with epoxy and similar materials.

For more information please contact me:

Norm Lambert
norm@epoxy.com
352-533-2167
www.epoxy.com

 


Basement Waterproofing with Epoxy

September 4, 2014

Many homes and businesses experience leaky basements year after year. The worse time is in the spring after winter accumulation of snow. There are a number of prudent things that you can do to improve drainage against your foundation like roof gutters, grading and improvement of drainage. The recommendations here do not replace that conventional wisdom. It is designed to augment and improve upon these conventional methods.

The following article will be 1 of 2. This one deals with Block wall foundations. The next one will deal with poured wall foundations.

Waterproofing Block Wall Foundations with Epoxy

One of the nicest features of most of our epoxies are that they are virtually 100% waterproof. Water simply cannot pass through a good healthy layer of properly applied concrete, block, wood etc. Epoxy also has an incredible bond to concrete, cement, wood and many other construction materials. The bond strength of epoxy to concrete and cement is greater than the tensile strength of the concrete. That means on properly prepared concrete, epoxy cannot be removed without pulling concrete with it. The same is true about wood.

Considerations in Waterproofing with Epoxy

All this gives you the perfect combination to make a block wall watertight. There are limitations however:

  1. In an ideal world the epoxy should be applied on the positive pressure side of the wall, the outside. This way the pressure of the water is pushing it into the wall. That helps to mitigate the likelihood that you get so much pressure on the concrete block that you fracture the block. Typically by the time you know you have a leak you are already backfilled and landscaped so 95% of the time it is not practical to do on the outside of the wall. So you do it on the inside instead.

    Water exerts a pressure of less than ½ psi per foot of water depth and most basement walls are only 8 foot high, so you would typically only see 4 psi. So it is unlikely that you have a pressure greater than the tensile strength of the block. So doing it on the inside is typically the only economical alternative.

  2. The Product #1W Epoxy is much more flexible than the concrete block and mortar, but if the mortar or concrete gets any significant cracks in it, it will crack through the coating. On the other hand, the system is very easy to patch if it does crack. We also make a wall grade version of our crack isolation membrane Epoxy.com Product #32 – www.epoxy.com/32.htm – which can reduce the potential for small cracks (which are the most common).
  3. A clean substrate is required for maximum effectiveness – www.epoxy.com/surfaceprep.aspx. For technical support contact me at norm@epoxy.com or 352-533-2167

Installation of Epoxy Waterproofing on Block Walls

Once the wall is clean, you need to point-up (fill) any cracks, bad mortar joints, and larger holes that are in the block. Some people use conventional mortar and wait 28 days for it to cure as per the American Concrete Institute. This is a very inexpensive way to do it, but can be affective if done properly. A more effective way to insure the right results is the use of Product #2005 Epoxy Gel Adhesive – www.epoxy.com/2005.aspx. That insures that you have a tight bond over the cracked areas and have already produced a tight waterproof seal in that area. Also the #2005 Gel Epoxy is semi flexible and allows more movement before cracking that conventional grout. The #2005 allows your coating to be installed the day after the #2005 is applied.

Once the cracks and holes are repaired, much of your work is done. You simply apply 1 coat of Epoxy.com Product #899 – www.epoxy.com/899.aspx – Epoxy Primer and allow to dry overnight.

After the primer has cured overnight you can apply the optional crack isolation membrane Product #32W – Wall Grade, or proceed to the coating below. If you do apply the crack isolation membrane 2 coats of the membrane are best. One advantage of the two coats of membrane is that typically you can reduce the number of coats of top coating that is required to seal the block. As you put on the membrane be sure to check to see that the holes in the block are being filled as you go.

Depending on the porosity of your concrete and if you used the crack isolation membrane above you will want to apply 2-4 coats of 1W epoxy wall coating. As you put on each coat check to see that the holes in the block wall are being filled.

Summary of Waterproofing Basement Walls with Epoxy

In conclusion: Leaking basements are a major problem to many structures in the spring. The easiest time to repair them is during the winter when there is little or no leakage. Epoxy.com epoxy coating systems can affectively and economically solve most basement leaking problems. The final product is a hard attractive ceramic like finish that does not require additional painting or other finishes over it.

Next Issue: Waterproofing Poured Wall foundations with Epoxy.

Additional Information on Epoxy Coatings

Product #1W (Wall Grade)  Epoxy Wall Coating – a general purpose epoxy wall coating

Product #2W (Wall Grade) Cemical Resistant Epoxy Wall Coating 

Product #32 (Wall Grade) Flexible Epoxy Membrane

Where to Start when installing epoxy.


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