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Geotech Training: Oct 26th - 28th, 2021

Posted by Kreg Thornley on Sep 14, 2021 10:00:00 AM

Banner - Geotech Training Fall 2021

SOLD OUT!

Sign Up to Get Notified for Future Training Events

Alchemy-Spetec HQ in Tucker, GA
Registration Deadline: Tuesday, October 12th

AS-Training-Program---Fall-2021$695 Registration Fee
$615 for each additional participant from
the same company.

Get ready for a thorough education in Slab Lifting, Soil Stabilization, the Alchemy-Spetec Deep Lift® process, equipment, and applications. You’ll get hands-on training from a technical staff with decades of on-the-job experience.

Tuesday, October 26th

  • Geotech Product Line Overview
  • Geotech Applications & Case Studies
  • PolyBadger® Demo & Training
  • Estimating & Quoting Jobs

Wednesday, October 27th

  • PMC Pump Demo & Training
  • Leak Seal Issues on Geotech Jobs
  • Ground Penetrating Radar Demo & Training
  • Slab Lift Rig Demo & Training
  • Competing Geotech Techniques

Thursday, October 28th

  • PolyShark® / Soil Stabilization Demo & Training (On-Site)
  • Deep Lift® Demo & Training (On-Site)

Your Instructors:

Andy Powell (Southeastern Regional Manager), Erik Prinzing (Midwest Regional Manager), Colt Hullander (Director of Technical Services - Geotech), Patrick Zito (Eastern Regional Manager), Joel Bryant (Western Regional Manager).

Topics: Equipment & Accessories, All Posts, Lift Slabs, Stabilize Soil, Business Tips, Deep Lift, Fill Voids

Sealing Water Infiltration in Leaking Joints, Inverts and Manholes

Posted by David Park on Sep 9, 2021 10:00:00 AM

Banner - Sealing Water Infiltration

Body - Sealing Water InfiltrationTreatment plants undergo massive strain and efficiency issues when groundwater infiltrates city collection systems. These common problems lead to large expenses that can accumulate if left unchecked. Identifying the root causes and creating a plan to minimize the damages will be dependent on the scale of the problems, the age and condition of your overall infrastructure, and your budget. Having a trusted, experienced team of consultants will prove to be invaluable as you navigate these uncharted waters.

What is Groundwater Infiltration?

Groundwater Infiltration is an industry term referring to groundwater improperly entering a sanitary sewer wastewater system. This water, which normally drains deep into the ground or is routed to storm drains, ends up being treated. This costly treatment will eat away at your already limited budget while also taking up precious capacity within your collection system. Some common ways groundwater can enter sewer pipes (interceptors, collectors, manholes, or side sewers) are through cracks, leaky pipe joints, connection failures, and poorly maintained manholes.

You may have groundwater infiltration issues if you notice any of the following signs:

  1. Your pipes are backed up during rainy seasons. This is often a good indicator of an unforeseen infiltration issue. During the next heavy rain, determine if your manholes are spilling wastewater onto local roadways or fields. This may be a good indicator that you have a surplus of groundwater infiltrating your wastewater systems.
  2. Your lift station pumps running continuously or cycling frequently. There may be an issue at hand if your lift station pumps run continuously for a long time after a typical rain event, or if your pumps start and stop frequently. Either event is likely happening because groundwater has entered your sanitary sewer system and is overloading your treatment centers.
  3. You can measure significant spikes in flow rates. As you measure and evaluate the effectiveness of your wastewater treatment plant during rainy or high groundwater conditions, readings that return abnormal spikes in inflow likely indicate an I&I issue. While small amounts of infiltration are to be expected, large spikes rarely happen unless there is a significant infiltration issue at hand.

6 Methods to Quantify Infiltration Issues

The warning signs noted above are helpful but indicate basic symptoms only. Once you’ve suspected that groundwater is infiltrating your system, there are 6 proven methods for capturing important data to determine the next course of action. These methods must be performed by a reputable engineering firm or a survey team.

  1. Sanitary sewer flow monitoring
  2. Manhole inspections and 3D technology
  3. Smoke testing
  4. Dye testing
  5. Pipe inspection/closed circuit television inspection (CCTV)
  6. Private property inspections

Cost-Effective and Proven Solutions to Stop Infiltration Immediately

These groundwater infiltration points can be permanently sealed off with crack/joint injection & curtain wall procedures using water-activated polyurethane foam. Pressure injection of these liquid polyurethane resins forces the material into leaking cracks, joints, or voids behind leaking structures. After the polyurethane injection is complete, the polyurethane resin rapidly reacts with water to form a watertight seal.

These leaks can be repaired with a small crew of about three people. A repair crew this size typically averages about two manholes per day (depending on manhole size and proximity). On average, curtain wall grouting a 4-foot diameter x 8-foot tall manhole requires 5 gallons of Spetec PUR HighFoamer. On average, treating joints and pipe penetrations on a 4-foot diameter x 8-foot tall manhole requires 2.5 gallons of Spetec PUR GT380.

  • Failing Sewer Pipe Joints: Groundwater rising and falling puts hydrostatic pressure on pipe and manhole joints, causing them to fail. Point grouting consists of driving injection pipes to the points of failure and injecting a resin such as Spetec PUR HighFoamer. The resin expands and cures quickly to seal off the leaks and fill voids in the soil. Filling the voids with a grout like Spetec PUR HighFoamer also reduces the hydrostatic pressure on the joints. The grout also permeates the soil and increases the load-bearing capacity which can prevent future misalignment of the pipes.
  • Pipe and Manholes Inverts: For many years, inverts have been repaired with hydraulic cement. But hydraulic cement fails if there is structural movement over the long-term, and thus leaking cracks/joint return. While hydraulic cement is cheap, repeating the repair process over and over is very expensive and means more confined space entries. Injecting the joints and inverts with a flexible polyurethane grout will provide a long-term repair, often longer than the expected service life of the manhole. Spetec PUR GT380 is the gold standard for these types of repairs, but at times a hydrophobic grout might be needed and thus Spetec PUR F400 would be the grout of choice. With the F400 different reaction times are possible by adjusting the percentage of GEN ACC Accelerator.
  • Precast Manhole Joints: A factory-trained specialty contractor can seal precast manhole joints using Spetec PUR GT380. It is a hydrophilic polyurethane material that cures to form a gel or a foam. Because it's a single-component material, you can install it easily without the need for mixing. It can easily penetrate joints before it eventually cures into place, thanks to its low viscosity. Spetec PUR GT380 is a durable, long-term sealing solution that holds up against the harsh sewer environment.

Want more information on leak seal products and equipment?

Download the Info-Packed Leak Seal Product Catalog!

Topics: All Posts, Seal Leaks

What Makes the PolyShark® Unique?

Posted by Colt Hullander on Sep 7, 2021 10:00:00 AM

Banner - What Makes the PolyShark Unique-1

Body - What Makes the PolyShark Unique-1It's not an exaggeration to say that that the PolyShark® soil stabilization and seawall repair pump system is unmatched in the marketplace. What makes it so unique?

A Geotech Pump System Like No Other

The PolyShark® system includes injection hoses, suction lines, flow meters, a custom solid steel frame, a skid-mounted setup, and top-of-the-line components. It is a complete turnkey unit, ready to go upon arrival. Let's take a closer look...

  • Two 350 feet injection hose reels are included, allowing an exceptional amount of additional reach for limited access and/or remote location jobs.
  • Suction lines make it easy to pump material from totes, drums, or even pails if needed. This type of flexibility is not common to all geotech pumps.
  • Flow meters make it easy to accurately track the amount of material pumped.
  • The custom solid steel frame, polyurea coated for excellent chemical resistance, is built to last and weather all types of environments.
  • The skid-mounted setup keeps all system components together, allowing for easy transfer from truck to trailer to the ground on a job site if necessary.
  • The Honda gas motor, Titan hydraulic pump, and Titan hydraulic fluid ram are top-of-the-line, tried, and true components. This means less maintenance and downtime when compared to competing systems.

Want more information on the PolyShark®?

Download an Info-Packed PolyShark System Brochure!

Topics: Repair Seawalls, All Posts, Stabilize Soil

Three Steps to Effective I & I Repair

Posted by Charlie "The Grout Geek" Lerman on Sep 2, 2021 10:00:00 AM

Banner - Three Steps to Effective I & I Repair

Body - Three Steps to Effective I & I RepairI&I is a major issue that plagues all collection systems. What can be done about it? There are a number of large-scale and costly ways to address it but often these are overwhelming projects to start. So, let’s take a step back and start small with the manholes. A quick review of rain event data will help pinpoint problem areas. There may be numerous issues in a line, but remember we are going for easy manhole infiltration. Start popping manhole covers. We don’t need to look for every minor leak and the large leaks are easy to identify. Obliviously, flowing water is easy to spot but even if a large leak is not active there are normally clear signs of its existence. These signs include staining, native soils being washed in, or joints with bulging ramnecks. 

So now, with X number of leaking manholes identified, it is time to set a plan. Inverts and precast joints are often the biggest culprits. Often, they have been previously repaired with hydraulic cement. But hydraulic cement can’t deal with movement, and thus leaking cracks return. While hydraulic cement is cheap, repeating the repair process over and over is very expensive and means more confined space entries. Injecting the joints and inverts with a flexible polyurethane grout will provide a long-term repair, often longer than the expected service life of the manhole. Spetec PUR GT380 is the gold standard for these types of repairs, but at times a hydrophobic grout might be needed and thus Spetec PUR F400 would be the grout of choice. 

But what about older brick manholes? Often they are ripped out and replaced. Replacement is not always necessary, can be disruptive, and is very costly. Spetec PUR Highfoamer is an excellent choice for curtain grouting (the ideal application for sealing gushing leaks in old brick manholes). Its set time can easily be field adjusted and its 50x expansion makes it very cost-effective. 

So to review...

  1. Perform a quick review of rain event data to identify potential leaks
  2. Pop manholes to identify large leaks
  3. Grout the defects for a long-term fix

The bonus round is to watch treatment costs drop due to less infiltration! 

Pro Tip: It is best to waterproof when the leaks are active.

Want more information on leak seal products and equipment?

Download the Info-Packed Leak Seal Product Catalog!

Topics: All Posts, Seal Leaks

How To Evaluate a Site for Deep LiftⓇ & Deep Stabilization

Posted by Andy Powell on Aug 31, 2021 10:00:00 AM

Banner - How To Evaluate a Site for Deep Lift & Deep Stabilization

Body - How To Evaluate a Site for Deep Lift & Deep StabilizationFor any Deep Lift or deep stabilization project, we want to gather as much information as possible about the project site.  This information falls into a few different categories, in no particular order:

  • The Cause(s) of the Settlement or Void

  • Information on the Structure

  • Geotechnical Data

  • General Observations and Measurements

  • Site Evaluation Tools

Now I will break down each category into a checklist. 

The Cause(s) of the Settlement or Void

It's important to identify the Causes of Settlement in a structure so that you can do a proper repair and not have the problem reoccur.  Things to look for include:

  • Broken pipes - is there a known plumbing issue, has it been resolved, have the drainage lines been scoped, are there unusually high water bills, have the owners observed persistent, soggy ground?
  • Are there stormwater or sewer culverts that run below the property?
  • Is there a seawall, retaining wall, or bulkhead supporting soil in the vicinity of the building?
  • Downspouts and gutter issues - do the downspouts discharge onto the ground next to the building or into pipes, are those buried drain pipes intact, are the gutters large enough to convey the rainwater to the downspouts, or do they overflow onto the ground next to the building?
  • Are there any known trash pits or large trees that have been taken out next to the building?
  • Do the building owners know any history about the site, was this building constructed on land that was already suspect?  Any kind of history you can get is valuable information.
  • Are there site drainage issues like water runoff coming in contact with the building?
  • Is there evidence of poor compaction?
  • Have there been any construction projects next to the property where dewatering has been done?

Information on the Structure

What kind of structure are we proposing to stabilize or lift? Information about the Structure includes but is not limited to the following:

  • Are there drawings, plans, or as-builts, for the structure?  Particularly we are interested in what kind of foundation the building is on.
  • Is the structure on pilings?
  • How deep are the footings?
  • How wide are the footings?
  • Are there interior strip footings?
  • Do the interior slabs rest on the footing or are they floating slabs?
  • What is the footing construction - poured concrete, concrete block, a combination of block on top of concrete?
  • Is the building structure made of wood, block, steel frame, poured concrete, a combination?
  • Is there siding or a brick facade on the building?
  • Is it a single or multi-story building?
  • Where are the plumbing and other utilities located?
  • Are there overhead power lines?
  • Can you reach the areas to be grouted with your equipment, do you have enough hose?

Geotechnical Data

Sometimes it is impossible to determine the causes of settlement without getting a Geotechnical engineer involved.  The kinds of Geotechnical Data we are looking for include:

Observations and Measurements

Finally, we need to put our Observations and Measurements together so we can complete the estimate, determine the full scope of the project, and set customer expectations accordingly.

  • How much has the structure settled?
  • Is the roofline affected?
  • Is the brick or block separating, are there stair-step cracks?
  • How many square feet of the interior slab has settled, how many inches down?
  • Perform soundings on the slab to determine if there are voids underneath.
  • Drill holes and use a probe or borescope camera to look underneath.

Tools for Site Evaluation

Of course, it is hard to get some of this information without the proper Tools for Site Evaluation.

  • Measuring wheel.
  • Camera for still pics and for video (I like to narrate my observations while I video record my walkthrough.  That way I don't have to remember what each still picture means.
  • Measuring tape.
  • Rotating laser with transit stick - or use a Zip Level to measure elevation changes.
  • Flashlight.
  • Drill.
  • Soil probe.
  • Borescope camera.
  • Drill hole patching material
  • Laptop, tablet, or a notepad and pen (for recording your information).

Want more information on the Deep LiftⓇ process?

Download an Info-Packed Deep Lift Brochure!

Topics: All Posts, Deep Lift

Three Resources for Finding Slab Lifting Jobs

Posted by David Park on Aug 26, 2021 11:00:00 AM

Banner - Three Resources for Finding Slab Lifting Jobs

Body - Three Resources for Finding Slab Lifting JobsI think you’ll agree with me when I say that, as a slab lifting contractor, you can never have too many leads. While there may be dozens of methods available, there are three very effective resources our customers strategically use to land new slab lifting projects on a regular basis. Let’s get started.

HomeAdvisor

HomeAdvisor can be a lead machine for residential slab lifting contractors. HomeAdvisor's online and TV marketing efforts draw in homeowners looking for local contractors of all kinds. You pay a membership fee, set a lead budget, and they feed you concrete leveling opportunities. But it doesn’t stop there. Here are some tips that can help you capitalize on those leads:

  1. Call the homeowner immediately: These leads go to multiple contractors so you need to be among the first to book an appointment.
  2. Pick specific zip codes: You can call HomeAdvisor and limit your advertising to higher-income zip codes, zip codes closest to your business, etc. Take some time to think through the reasons for targeting specific areas. For example, higher-income homeowners tend to care more about quality than price, jobs near your business reduce travel costs, and so on.
  3. Dispute bad leads: Some leads will come in that aren’t relevant. For example, the homeowner didn't realize they were choosing the wrong job type category, or they just wanted to ask some questions but did not actually have a project available. You can dispute these types of leads via HomeAdvisor's website or by calling their customer service line.

Google Ads

Google is the most popular search engine in the world. Our top customers have learned to leverage Google's massive user base through implementing strategic Google Ads campaigns. They use Google Ads to target local people who are searching for specific keywords such as "concrete leveling contractor near me" or "sinking driveway repair", etc. This means you can continually refine your parameters so that the most relevant leads end up on your landing page. 

It's important to design a custom landing page for your Google Ads campaign, encouraging the visitor to download a brochure for more information. Your brochure download process should require the lead to enter their contact info. Some people recommend excluding website navigation menus on these pages, effectively requiring the visitor to download the brochure. In this way, you capture contact info from all types of visitors - even those who are not ready to buy yet but are in the information gathering stage. These types of visitors would otherwise scour a conventional website, take notes, and then continue searching without ever sharing their contact info.  If you need someone to create your Google Ads campaign and/or landing page, we can put you in contact with experienced freelancers.

This next section is excerpted from our brochure, Marketing Your Contracting Business. (The brochure download link is at the bottom of this article.)

Blogging for Leads

Cast a Wide Net with a Lot of Posts

The more pages you have on your website, the more chances there are for someone to find it when searching a specific phrase or term. Search engines are scanning your page names, heading text, and page text when someone types in a term or phrase to see if there are any matches. So, it’s in your best interest to have as many pages full of relevant content as you can. A blog is a perfect way to accomplish that goal.

Say, for example, that you are a slab lifting contractor in San Pedro, California. You can write up case studies of jobs you’ve performed in your area. Make sure your blog titles include terms people will likely search for. For example, a post about a warehouse floor job could be titled, “Warehouse Floor Slab Lift in San Pedro”. You get the idea.

Share Your Knowledge and Build Trust

You can also use a blog as a way to share your knowledge and experience with potential customers who are looking for answers. Take some time to consider all that you’ve learned over the years and jot down ideas for blog posts that potential customers may find helpful. In addition to case studies, you can write posts instructing people how to spot problems on their property, comparing your repair costs to the costs of replacing a structure, educating people about the materials you use, etc.

You can get quite a few ideas by browsing the posts on our blog. While our articles are aimed more at contractors than property owners, you’ll still find many useful subjects to get your brainstorming started. The more useful knowledge you share, the more trust you can build with potential customers. People are much more likely to buy a service from a known expert than from a complete stranger.

Offer More Value in Exchange for Contact Info

Driving up web traffic is a good thing. Establishing yourself as an authority by creating useful content is also very helpful. If you just do those two things, you should get more people calling you and filling out the contact form on your website. But if you REALLY want to jumpstart the leads, you need to offer something of value in exchange for your reader’s contact info. At the end of every article, include a link to a relevant brochure – or something else of value – and ask for their contact info in exchange. For an example, see the form download button at the bottom of this article.

The Gift That Keeps on Giving

The great thing about a blog post with a lead capture form at the end is that, once you set it up – it’s there forever. We still get leads from blog posts we put up years ago. If you consistently write articles, you can create a compounding effect with more and more leads coming in each month.

Want more information on lead generation?

Download an Info-Packed Contractor Marketing Brochure!

Topics: All Posts, Lift Slabs, Business Tips

INJECTR Series 4 Pack: Complete Grab & Go Leak Seal Solution

Posted by Kreg Thornley on Aug 24, 2021 10:00:00 AM

Banner - INJECTR Series 4 Pack

Compatible with a Standard Caulk Gun

Body - INJECTR Series 4 Pack Kit

INJECTR Series cartridges feature Spetec PUR F400 or Spetec PUR HighFoamer and GEN ACC Accelerator in two sides of the same cartridge. The grout mixes with the accelerator when injected. No need for a full crew or a grout pump. Quicker in and out - less labor.

Available in a Convenient 4 Pack Kit

Both the Spetec PUR F400 and the Spetec PUR HighFoamer kits Include:

4 - Cartridges
4 - Static Mixers
8 - 1/2” Drill Ports
4 - Large Push Connects
4 - Small Push Connects
1 - 10 ft Roll Flexible Tubing

12 Pack Cartridge Case Also Available

Want more information on Alchemy-Spetec leak seal solutions?

Download the Info-Packed Leak Seal Product Catalog!

Topics: All Posts, Seal Leaks

How to Select the Right Grout for Crack Injection

Posted by Charlie "The Grout Geek" Lerman on Aug 17, 2021 10:00:00 AM

Banner - How to Select the Right Grout for Crack Injection

Body - How to Select the Right Grout for Crack InjectionConcrete is the most common building material in the world. While it has high compressive strength, it does not have much tensile strength. It is only since about 1910 that rebar has been specified. Reinforced concrete can and does still crack. So does that matter? Yes, most of the time it does matter.

Epoxies Are for Structural Repair

Epoxies are commonly and very effectively employed to “weld” these cracks back together. End of story, right? Of course not. For structural repairs epoxies are correct and necessary, but what about non-structural dynamic cracking? Well first off, why do we even care if there is a non-structural crack? Sometimes we don’t, but when this non-structural crack is the source of water intrusion action is required!

Water intrusion, besides being unsightly can cause many problems. Slip hazards are an obvious one, remember that rebar we started adding back in the 1910s? It can corrode, per NACE it can expand about 7-8 times its size, causing spalling and even complete failure of the concrete. Epoxy repair of a dynamic non-structural crack does not end well. The crack is there to relieve stress and if it is welded together with epoxy then it cannot move to relieve the stress, which causes what we call mirror cracking (this is a new crack in proximity to the previous epoxy repaired crack). Now we are back to where we started and we wasted time, labor, and materials on a failed repair.

Polyurethanes Are Ideal for Sealing Leaks

Flexible polyurethane grouts are ideal for dynamic cracks. They will waterproof the crack but still allow the cyclic movement - thus no mirror cracking, no leaks, and no corroding rebar. There are two main categories of polyurethane grouts, hydrophilic and hydrophobic. Hydrophilic grouts have more flexibility (higher tensile strength) and better adhesion than hydrophobic grouts. So, the answer seems clear, choose a hydrophilic grout. Hydrophilic grouts are the first choice for most below-grade applications, but since they form an open crosslinking when they polymerize, they can dry out in arid environments. Hydrophobic grouts have a closed crosslink and therefore are unaffected by wet-dry cycling, but have less elongation and lower adhesion strength. So, if you're new to this, it's best to consult an expert when selecting a polyurethane for your leak seal job.

Technical Support for Leak Seal Contractors

When it comes to waterproofing with chemical grouts, product selection and application techniques will make or break a job. Good technical support ensures more production and less product waste. I have over two decades of field experience. I'm happy to share that knowledge in support of all your waterproofing needs, and I am just part of the most experienced grouting tech service team out there. We pride ourselves on education and training in the field, in the classroom, and online. Please let us know how Alchemy-Spetec can be of assistance to you. Call our tech support team today at 404-618-0438.

Want more info on leak seal products and equipment?

Download the Info-Packed Leak Seal Product Catalog!

Topics: All Posts, Seal Leaks

Hydraulic Cement vs. Chemical Grout: What is Best for Leaks?

Posted by Charlie "The Grout Geek" Lerman on Aug 12, 2021 10:00:00 AM

Banner - Chemical Grout vs Hydraulic Cement for Leaks and Infiltration

Body - Chemical Grout vs Hydraulic Cement for Leaks and IIn this post, I’m going to personally review two popular methods used to handle water leaks and infiltration. Both hydraulic cement and chemical polyurethane grouts are used in civil applications such as sewer pipe rehabilitation, tunnel or shaft construction, sealing leaking cracks in concrete structures, permeating soil to control the flow of groundwater, filling voids to stabilize soil, and handling common inflow and infiltration issues found all over the world.

This post will reveal the good, the bad, (and the ugly) when it comes to product selection and application. When considering chemical grout or hydraulic cement for your waterproofing needs, we will need to look at:

  • Features
  • Costs
  • Applications

When it comes to waterproofing with chemical grouts, application techniques will make or break a job. There is a lot of misinformation out there, so I encourage you to carefully evaluate the content below and make the most educated decision for your upcoming projects. (For further assistance with that decision, feel free to call our tech support team at 404-618-0438.)

Before we continue, I’d like to briefly let you know who I am and what I do. My name is Charlie Lerman (a.k.a. The Grout Geek). I was the Technical Field Services Manager at two industry-leading polyurethane grout manufacturers for 18+ years before joining Alchemy-Spetec as the Director of Technical Services – Leak Seal Division. My full-time responsibility is to take care of your questions and uncertainties concerning waterproofing with chemical grout and alternative options. So when is it best to use hydraulic cement? When should you use chemical grout? Let’s compare:

What is Hydraulic Cement? Key Features

Hydraulic cement is inexpensive and easy to apply but its benefits stop there. It is a surface patch that is primarily applied to the negative side. It has a weak adhesion and thus is applied in a groove or similar cut. It can be used to shut down low-pressure leaks. Being that it is cement it has a low tensile strength which means just like other types of cement it will be brittle when it is cured.

Chemical Grout Features

There are two primary types of chemical grouts when it comes to crack injection, each unique in its composition and makeup: (1) acrylics and (2) polyurethanes.

1. Acrylic grouts are free of suspended solids and have extremely low viscosity. The grouts can change from a liquid to a solid in a controllable gel time ranging from 3 seconds up to 10 plus hours. The lifespan of acrylic grouts is estimated to be between 50-300 years depending on the method and application utilized. Acrylic grouts are hydrophilic, have about 500% elongation, and are only about 20 cps. These properties make them ideal for injecting hairline cracks. Alchemy-Spetec's Spetec AG200 acrylic injection resin is NSF 61-5 certified for contact with drinking water.

2. Polyurethane grouts can be grouped into two types: hydrophilic and hydrophobic. Hydrophilic grouts are usually single component formulations that react with water and cure to an expansive flexible foam or non-expansive gel requiring a moist/humid environment after curing. Hydrophobic grouts are expansive foams that require little water to react and can easily withstand wet/dry cycles. Hydrophilic foams expand 4 to 6 times their original volume, while hydrophobic foams can expand up to 40 times their original volume and may cure flexibly or rigidly. Alchemy-Spetec offers many polyurethane resins that are NSF 61-5 certified for contact with drinking water. The lifespan of polyurethane foam is estimated to be approximately 70+ years.

Both acrylic and polyurethane chemical grouts are injected into cracks or joints and thus are not considered a negative side waterproofing even though they are often applied from the negative side. Acrylic and flexible polyurethanes are designed to shut down active leaks and, because of their high tensile strengths, they can withstand the movement of a dynamic crack or joint. Because they are full-depth repair materials, they can also encapsulate rebar and thus help prevent corrosion, spalling, and thus structural failure.

Applications: When, Where, and Why

I cannot emphasize enough how helpful it is to speak with an experienced grout consultant and/or an experienced contractor when faced with the need to stop leaks or control inflow and infiltration. If you are looking for installation recommendations, a knowledgeable grout manufacturer should be consulted to assist with proper grout selection and installation methodology. I am available to assist with your next project. Call Alchemy-Spetec at 404-618-0438 and ask for the Grout Geek!

Want more information on leak seal products and equipment?

Download the Info-Packed Leak Seal Product Catalog!

Topics: All Posts, Seal Leaks

Stabilizing & Lifting a Bridge Approach Slab with Polyurethane

Posted by Andy Powell on Aug 10, 2021 10:00:00 AM

Banner - Stabilizing and Lifting a Bridge Approach Slab with Polyurethane

Body - Stabilizing and Lifting a Bridge Approach SlabLifting a settled bridge approach slab with polyurethane foam requires specific knowledge of proved repair procedures for these types of structures. Here's an overview...

Look for a Hidden Sleeper Slab

Larger roads and highways will often have a hidden sleeper slab that spans underneath the pavement and the approach slab. It is designed to help transfer the traffic load from the roadway to the approach slab. If there is settling at a bridge approach you must determine if there is a sleeper slab in place. Drill through the pavement where it meets the approach slab and if you hit more concrete underneath the pavement you have found the sleeper. If there is a sleeper present where there is settling you will need to perform deep injection a couple of feet below the sleeper - just for soil stabilization. Rural roads and private roads typically do not have a sleeper slab present. Always ask the client if there are drawings available.

Deep Soil Stabilization Followed by Lifting

At least one level of deep injection is required for approach slab/pavement lifting. This is for soil stabilization. 4' spacing and 4' below the pavement is standard. Do not exceed more than 30 lbs per point at a given depth. It is advised to always have a DCP (dynamic cone penetrometer) test done in order to determine the blow counts. Low blow counts indicate weak soil zones that need to be targeted for deep injection. Lifting will be done directly through the pavement/approach slab, the same way you do standard slab lifting. Do the deep injections first and then finish with the injections directly beneath the slab.

Fill Voids with Polyurethane

Watch for voids under the approach slabs where they meet the bridge abutments. There are typically voids in this area that need to be filled. When filling them, it is good to have an observer under the bridge because the foam can fill the void up and come over the abutment, depending on how the structure is designed.

Want more info on geotech repair products?

Download the Info-Packed Geotech Product Catalog!

Topics: All Posts, Lift Slabs