Alchatek Blog

Alchemy-Spetec is pleased to announce that our VP of Sales and Business Development, Jim Spiegel, recently completed Tier 1 of ICRI's Concrete Repair Technician Program.  As the industry leaders in technical support for contractors, distributors, and engineers, we pride ourselves in a company culture that encourages ongoing technical training for employees and executives. 

More on the ICRI Concrete Repair Technician Certification Program from ICRI website...

This online certification program was developed based on industry demand and...outlines repair inspector qualifications for the inspection of concrete repairs, and designates an individual who has been certified as an ICRI Concrete Surface Repair Technician, as a qualified inspector.

The Concrete Surface Repair Technician Certification Program is a competency-based program using current best practices for online training and evaluation. The Educational component is presented and tested online while the Performance component is tested both online through a knowledge exam and assessed by observable criteria (video submission or live recorded).

Tier 1 only applicants are those who may not be regularly engaged in concrete surface repair inspection and testing, yet have an active interest in learning more about the inspection and tests, be introduced to types of concrete deterioration, understand the requirements for a quality concrete surface repair, be aware of repair materials and methods, and be qualified to perform pre and post-placement inspections and testing.

Learn more about the ICRI Concrete Repair Technician Certification Program...

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Get ready for a thorough education in polyurethane slab lift/soil stabilization geotech products and applications on Thursday, October 10th (October 9th is leak seal day), 2019 at Alchemy-Spetec HQ in Tucker, GA. You’ll get hands-on training from a technical staff with decades of on-the-job experience. Registration includes both days, but we’ll take a close look at the geotech curriculum in today’s blog post…

The schedule on Thursday, October 10th includes education on the Alchemy-Spetec geotech product line, soil stabilization, slab lifting, the Deep Lift™ process, rig & mobile lifting systems, geotech accessories, soil testing (ground penetrating radar, penetrometer), pricing and estimating. There will also be live geotech demos, product mixing demos, and open discussions for sharing job related tips and solutions from the field.

Your instructors have years of experience providing technical support for contractors across the country. You can look forward to presentations, demos and/or discussions lead by Stephen C. Barton (President/CEO), Jim Spiegel (VP Sales & Business Development), Andy Powell (Southeastern Regional Manager), Anthony Sandone (Eastern Regional Manager), and Charlie Lerman (Western Regional Manager). 

Participants will receive a Samsung tablet loaded with leak seal training material.

Sign up while there's still space available...

Get ready for a thorough education in polyurethane leak seal products and applications on Wednesday, October 9th (October 10th is geotech day), 2019 at Alchemy-Spetec HQ in Tucker, GA. You’ll get hands-on training from a technical staff with decades of on-the-job experience. Registration includes both days, but we’ll take a close look at the leak seal curriculum in today’s blog post…

The schedule on Wednesday, October 9th includes presentations on the Alchemy-Spetec leak seal product line, crack injection, curtain grouting, permeation grouting, pumps & packers, leak seal accessories and municipal applications. There will also be live injection demos, product mixing demos, and open discussions for sharing job related tips and solutions from the field.

Your instructors have years of experience providing technical support for both contractors and distributors across the country. You can look forward to presentations, demos and/or discussions lead by Stephen C. Barton (President/CEO), Jim Spiegel (VP Sales & Business Development), Andy Powell (Southeastern Regional Manager), Anthony Sandone (Eastern Regional Manager), and Charlie Lerman (Western Regional Manager). 

Participants will receive a Samsung tablet loaded with leak seal training material.

Sign up while there's still space available...

Concrete will crack – that is a fact. When cracks appear, they are dynamic or static, and structural or non-structural. If the crack is static, non-structural, and does not leak, epoxies are great to restore design strength. However, since concrete constantly shrinks, expands, and often leaks, the use of a flexible polyurethane resin to permanently seal active leaks is the optimum choice to create a leak-free environment.

Water leaking through concrete is as old as concrete itself. Any leaking structure is problematic. These issues range from reduced lifespan to liability and lawsuits. This paper will discuss the mitigation of leaking structures to facilitate its coating. Often, these cracks are dynamic in nature. Static or structural repair of dynamic cracks will fail when the concrete needs to “move” again. Flexible polyurethane grouts can be used to mitigate water intrusion. This will extend the life of the structure and is a crucial step in surface preparation for most coatings.

Why Concrete Cracks

Concrete will crack - that is a fact. But to treat the crack, you need to understand the nature of cracking. There are four categories of cracks: static, dynamic, structural and non-structural.  A crack normally falls into two of the four categories. Just as the names imply, a static crack is non-moving, and a dynamic crack moves. Structural cracks place the integrity of the structure in jeopardy, while non-structural cracks can be eyesores and allow water infiltration. 

Static cracks are the result of a one-time event. This may be a thermal or shrinkage crack that formed while the concrete cured, or from a damaging event like a car hitting the concrete.  Typically, these structures do not move which is the driving force to why they are no longer used today.

Dynamic cracks expand and contract due to reoccurring force(s). The forces include, but are not limited to, freeze/thaw cycles, rapid thermal changes, loading of the concrete, and expansive soils. If the joint’s design was not adequate to deal with these forces, the concrete will often crack. “Cracking in concrete is affected by the long-term conditions to which the concrete element is subjected. In most cases, long-term exposure and long-term loading extend the magnitude of cracks, principally their width, in both reinforced and plain concrete." (ACI 22R-01 2001).

External forces are usually repetitive and cause the crack to expand and contract. These cracks are not a structural concern, but water infiltration through these cracks can be a serious problem.

Epoxy vs. Flexible Polyurethane

In spite of the best efforts of the architect, engineer and contractor, structures will sometimes move in unanticipated ways causing cracks to appear. Resin can be injected into the concrete to accomplish one of two purposes:

1. Restore design strength
2. Stop water leakage

If load bearing members such as walls, beams or columns are weakened, injection of high strength epoxies may be appropriate. However, more often than not, the concern with cracking is water infiltration. Epoxies are designed to be strong with little to no elongation, and chemically bond the concrete back together which is not appropriate for a dynamic, leaking crack. Epoxy will be stronger than the concrete and will cause the concrete to crack nearby. Lastly, the majority of epoxies are water intolerant and not suitable for waterproofing.

Crack / Joint Injection

Examination of the crack or joint after cleaning tells us where the crack goes and how wide it is. The surface should be cleaned mechanically. Loose debris or patches should be removed to reveal the crack. To maximize results, it is best to inject an actively leaking crack.

Injection should start from the lowest point of a vertical crack or the narrowest side of a horizontal crack. Injection holes should be drilled at a distance away from the crack that is equal to half the wall’s thickness (Example: If the wall is 8” thick, drill your hole 4” from the crack). This forms an isosceles right triangle when drilling at a 45 degree angle, and ideally intersects the crack or joint at its halfway point through the wall.

A low viscosity, flexible polyurethane grout should be injected.  Polyurethane grout will react with water to form a “custom gasket” that has three different bonds - adhesive, mechanical, and compressive. “The aim of all injection processes is to obtain uniform penetration of the resin and complete filling of the crack.” (Perkins 2003). Urethanes are very chemical resistant, but always check with the manufacturer about specific chemical resistances for a project.

Patience is important in resin injection work - slow is better. Always start injecting with the pump set at the lowest setting.  I like to say “If crack injection is not slow and painful, you are doing it wrong.”

Case Study: Vault Coating Failure

A below grade concrete precast vault was epoxy coated during a summer, the dry season, in the Pacific Northwest. The following winter coating failure was observed only at the joint.  There was also indication of water intrusion and rundown (see Photo 1).

Photo 1
Inspection of the vault lead to the belief the failure was caused be water intrusion through the precast joint. In 2012 the joint was injected with a flexible hydrophobic grout (Photo 2).

Photo 2
After a number of months of observation with no water intrusion the coating was repaired and is still in service till today with no defects.

Curtain Grouting

Curtain grouting is a method of installing a waterproofing membrane on the positive side of a below-grade structure without excavation. Curtain grouting is appropriate when there is spider web cracking or extensive cracking of the concrete.  It is not possible to address a large number of cracks in proximity with crack injection due to the number of injection holes needed.  Often, curtain grouting is easier than crack injection, but more material intensive.  Curtain grouting is an excellent fix because even if the concrete continues to crack, there will be no leaks as the water is no longer in contact with the structure.

Summary

A coating manufacturer once stated “It is estimated that 85%+ coating and lining failures are due to inadequate surface preparation.” Moisture mitigation is a large percentage of that and must be addressed.  For dynamic cracks, flexible polyurethanes are one of the best repair methods out there.

Want more information on Alchemy-Spetec leak seal products?

As a member of the ICRI Board of Directors, I'm happy to share the following information about the upcoming ICRI Webinar: Specifying Concrete Repair.

Time and Date:
Wednesday, July 31, 2019
1-2 PM CDT / 2-3 PM EDT

This webinar will review issues that should be addressed when preparing a specification for concrete repair. ICRI developed an editable specification titled “Guide Specification for Structural Concrete Repairs” that can be used by design professionals. The webinar reviews the specification and discusses decisions that should be considered when developing a concrete repair specification.

Learning Objectives

1. Become familiar with ICRI Technical Guide No. 110.1, “Guide Specifications for Structural Concrete Repairs,” based on the CSI (Construction Specifications Institute) Masterformat.
2. Understand the breakdown of key information in the three parts of the specification: Part 1: General, Part 2: Products, and Part 3: Execution.
3. Understand the decisions made by the committee during the development of the specification. 
4. Be introduced to the decisions that will need to be made by the Design Professional when using the specification.
5. Learn the standard practices commonly used in the concrete repair industry, with options and commentary, and how to require them through specifications.

About the Presenter

Karl Rickert, PE, was born in Baltimore, Maryland and raised in Arnold, Maryland.  Thanks to familial connections, his father was a structural engineer. Karl obtained a job at Lamprecht Consultants, a structural engineering firm in Baltimore, where he worked during the summer after his junior year in high school until about 2 years after finishing college.

Between 1971 and 1975, Karl attended Drexel University, participated in their cooperative education program and became a student member of the American Society of Civil Engineers.  Following graduation with a BS in Civil Engineering, Karl spent the next 11 years gaining experience as a structural engineer through work at Lamprecht Consultants, Skarda & Rickert Structural Consultants, and Whitney, Bailey, Cox & Magnani.  In 1979, Karl became a registered professional engineer in the State of Maryland and is currently registered in eight states and the District of Columbia.  Karl completed an MS in structural engineering at George Washington University in 1984.

In 1986, Karl founded Rickert Engineering, Inc. and continues to serve as President of the firm.  Karl completed an MBA at Loyola College in Baltimore in 1994 and has maintained memberships in professional organizations including ACI, ACEC, AISC, ASCE, CSI, ICRI, and NSPE.  He has been an officer at the local level of several of these organizations and is currently active on committees (past-chair of Committee 110) at the national level of the International Concrete Repair Institute.  He is also currently serving on the Maryland Board of Professional Engineers.

In this post, we’re sharing our three most popular articles on sealing seawalls over the last 365 days.  Read the opening paragraph, and then click "Read more..." for the rest of the article.

1. Stop Erosion Through Your Seawall with Polyurethane

When it comes to seawalls, there is a lot more to learn than meets the eye. A seawall is like a living, breathing thing: especially in the way that it is designed to function. But like all living breathing things, they have a finite lifespan. For many of them, it's a mere 20 – 30 years. Depending on where you live, replacing a seawall can cost anywhere from $150 to $500 per foot. That's enough for some homeowners to choose to move instead of rebuilding their seawalls. Today however, signs of seawall distress can be solved before they get too bad through the application of polyurethane grouts to seal leaks, fill voids, and stabilize the surrounding soils. Read more…

2. An In-Depth Look at Polyurethane Seawall Repair

In this article we look at an innovative way to repair seawalls instead of replacing them by stopping high flow leaks, filling the voids behind concrete structures and binding loose soil with polyurethane foam. The underlying cause of seawall deterioration is as follows: As tidal flows rise and fall, water pushes its way in through cracks, joints, and defects in seawalls. The water pushes in on incoming tides and flows out on outgoing tides. As the water flows out, it carries sand and soil with it which causes undermining of the structure, voids to form, and deteriorates the structural integrity of the seawall. This cycle is exacerbated during periods of heavy rain which continue the outflow of soil. Read more…

3. Signs a Seawall is in Need of Repair

Salt corrosion, tidal action, currents, boat wakes, storm surges and sometimes hurricanes all deliver a constant beating on the seawall. Contrary to popular opinion, many of the forces also come from the side of the wall facing the land. Did you realize that rainfall/storm events create more hydrostatic pressure than rising and falling tides? Every time it rains or the irrigation system runs, and every time the tide goes out; all of the groundwater above the waterline needs a place to vent or equalize. Massive pressure can build up if that water is trapped, making it impossible for it to drain into the sea or storm water system. That is a recipe for disaster which can easily be avoided with proper surveillance. Read more…

Want more information on sealing seawalls?

Does Your Seawall Need Sealing?

In general, seawalls protect property from erosion over time and from damage during extreme weather. But this is only the case when the seawall is not leaking. If your seawall is compromised, consider having it sealed with polyurethane resin. (To determine if your seawall is compromised, see our blog post Telltale Signs Your Seawall May Need Repairs.) The key to keeping problems at bay is to actively anticipate them. Regularly inspect your seawall or call us at 404-618-0438 to help you find a professional to inspect it for you.

Polyurethane Products for Seawall Sealing

AP Fill 700 and Spetec PUR H200 are both semi-rigid hydrophobic polyurethane foams that react with moisture in the soil and expand to fill voids while permeating sandy soil to form a solid, strong, watertight mass.  These are the two most commonly used foams for sealing seawall cracks, voids and defects (as well as for filling voids and stabilizing soil).  

Andy Powell summed it up perfectly in Signs a Seawall is in Need of Repair...

If you live along the water, it is always going to be man against nature. That seawall is keeping your property from damage and from disappearing altogether. The key to extending the life of your seawall is the advanced polyurethane technology from Alchemy-Spetec. For more on the repair process itself, read An In-Depth Look at Polyurethane Seawall Repair. It's fast, clean, easy to install, and most of all, effective.

Want more info on Alchemy-Spetec seawall repair products and applications?

Seawalls embody the very image of long-lasting endurance and stability. Without proper maintenance and repair, however, the reality can be a bit different.  If your seawall is showing any of the signs listed below, you may want to look into repair options.

Here some telltale signs your seawall may need repairs...

• Clogged Weep Holes
  Weep holes are small openings in concrete structures that allow water from behind the seawall to drain through it.  If these holes get clogged with debris, water pressure can build up and cause the wall to eventually crack and fail (or cause the water to find ways around the wall).

• Visible Rust Colored Cracks/Stains
  Rebar that has been exposed to water will stain the surrounding area. This causes the rebar to expand, further introducing cracks into the seawall and risking failure.
  
  
• Sinkholes or Settling Concrete Near the Seawall
  Sinkholes or settling concrete appear due to loss of soil. This is essentially a feature of a compromised seawall in that water is seeping through or underneath the seawall, weakening the structure and contributing to soil erosion.
  
  
• Sand or Soil Deposits on the Water Side of the Seawall
  These deposits will typically show up at the joints and are a sign that you are losing soil from behind the seawall.

Solution - Polyurethane Seawall Repair

I summed it up in this previous blog post An In-Depth Look at Polyurethane Seawall Repair...

Polyurethane installation equipment and procedures allow for a non-invasive, clean approach to repair that often allows the property owner to continue use during the process. In all cases, the property owner can resume activity on and around the structure within hours after a repair. As explained in our blog post Alchemy-Spetec's NSF Certification Spells Environmental Protection, most of our products have been rigorously tested not only for contact with typical recreational and commercial bodies of water, but even for contact with drinking water. So there is NO doubt about the environmentally friendly advantages of Alchemy-Spetec seawall repair materials.  Read more...

Want more info on Alchemy-Spetec seawall repair products and applications?

Using oakum with chemical grout is a way of sealing gushing leaks, as well as sealing the area (annular space) around pipes passing through concrete structures. When a pipe passes through a concrete structure and the annular space around the pipe is large, the saturated oakum technique can be used to seal off the water infiltration. Oakum saturated with grout can be used alone to seal off water flow. It can also be utilized to build a surface seal or “dam” behind which grout can be pumped. 

Procedures

This is a two-person process.

1. Clean the crack or space to be sealed of any loose debris and foreign material.
2. Cut the oakum in various lengths to fit the perimeter requirements of the area to be sealed.
3. Soak the oakum in the grout.
4. One person will wring out the soaked oakum and hand it to the other person, who will...
5. Dip the oakum into a pail of water to activate the grout and then place the activated oakum into the crack or space using a screw driver or a similar tool.

After the space has been packed with saturated oakum, you can inject grout behind the seal with an injection needle. 

For more information, see our previous post on this subject and call us at 404-618-0438.

Want more information on Alchemy-Spetec leak seal products?

Don't miss out on the AP Lift 430 and MixMaster Pro slab lifting gun product bundle offer!

AP Lift 430 Concrete Leveling Foam

AP LIFT 430 is a two component, high strength, high density, hydro insensitive slab lifting foam. 

• Traffic ready in 15 minutes.
• High strength.
• Works in wet environments - displaces water.
• Bonds with soil and concrete.
• Closed cell.
• Certified by Truesdail Labs to NSF/ANSI 61-5 (approved for contact with drinking water).

MixMaster Pro Concrete Leveling Gun

Two-component resin injection gun manufactured specifically for lifting concrete slabs, designed to handle back-pressure. As the essential piece of foam jacking equipment for Alchemy-Spetec’s expanding polyurethane foams, the resin injection gun provides highly-efficient concrete leveling. 

• Completely mechanical actuation
• No side seals or O-rings in the mixing block to replace
• Integrated rebuildable check valves to save your whip hose
• Easy break down and clean up at the end of the day
• Utilizes smaller 3/8” injection port
• Uses water based flush

Call 404-618-0438 to order your Slab Lift Product Bundle NOW!

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