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Hollow Core Concrete Slab Water Leak Repair

Hollow Core Concrete Slab Water Leak Repair

What is a Hollow Core Slab ?

Hollow core slabs are precast, prestressed concrete members commonly used to construct floors and roofs in multi-story buildings, parking structures and other commercial construction.

As the name suggests, longitudinal hollow cells run through the interior of the slab. These voids reduce the amount of concrete required and the weight of the structural member while maintaining an efficient structural cross section.

For waterproofing contractors, however, those same hollow cells create a unique challenge.

If water enters an unsealed end, joint, penetration or other opening, it may collect inside a cell and travel through the slab before finding an exit. As a result, the location where water appears is not necessarily the location where water entered the structure.

This makes proper investigation especially important when repairing hollow core slab leaks.

Hollow Core Concrete Slab Water Leak Repair

Diagnosing and Sealing Water Intrusion in a Parking Garage with SealBoss 1510 Water Stop Foam

A water leak in a hollow core concrete slab is not always as straightforward as it appears.

Water dripping from a crack in the ceiling may have entered the structure several feet away. Once water reaches the hollow cells inside a precast slab, those concealed channels can collect water and allow it to move beyond the original point of entry.

That was the challenge on this parking garage repair project.

The visible symptoms were leaking cracks, water dripping onto parked vehicles, staining and efflorescence. But simply injecting the locations where water appeared would not necessarily solve the complete problem.

The contractor first had to determine where the water was entering, where it was traveling, and how it was escaping from the hollow core slab system.

The Problem: Water Dripping Into the Parking Garage

The building owner was experiencing water intrusion through hollow core concrete slabs and along exterior wall and sill plate cold joints above a parking garage. Water was dripping onto vehicles below and leaving visible watermarks, efflorescence and rust staining on portions of the concrete and walls. A waterproofing contractor was brought in with two objectives:

  1. Stop the active leakage through the cracks and joints.
  2. Determine the source of the water entering the hollow core slab system.

The second objective proved to be just as important as the first.

Finding the Source of the Water

Before beginning injection work, the contractor and SealBoss Regional Sales Manager inspected the exterior of the building. A significant drainage condition quickly became apparent. Downspouts were discharging stormwater directly onto grassy areas adjacent to the building. The surrounding grade provided little slope to move the water away from the structure, allowing runoff to collect near the exterior wall.

This provided an important clue.

Rather than treating the ceiling leaks as isolated cracks, the repair team investigated whether exterior water was entering through the building perimeter and reaching the hollow core slab cells. The evidence soon confirmed it.

The Hollow Core Was Holding Water

When drilling began for installation of the injection packers, water poured from the slab. The hollow core cell was not simply damp—it had accumulated a substantial amount of water. Before injection could proceed, the trapped water was allowed to drain.

But the investigation did not stop there.

Because water can migrate through openings and interconnected areas within a hollow core assembly, weep holes were drilled into adjacent cells to determine whether the problem extended beyond the first affected core. Water was discovered in another cell as well. That cell also had to be drained.

This was an important part of the diagnosis: The visible ceiling leak represented only one portion of a larger concealed water-intrusion path.

A Borescope Revealed the Entry Point

To investigate farther inside the slab, the contractor used a borescope. The inspection confirmed water intrusion near the location where the hollow core had been closed with a plastic end cap. The combination of exterior drainage observations, water discovered inside the slab cells and the borescope inspection provided a much clearer picture of the leak mechanism.

Water was reaching the building perimeter, entering the hollow core system and accumulating inside the cells before eventually escaping through cracks and joints into the parking garage below. With the leak path identified, the repair could address both the visible leakage and the likely entry locations.

A Two-Part Injection Strategy

The contractor adopted a two-part repair strategy.

Step 1: Seal the Leaking Cracks

The first objective was to stop water escaping through cracks in the hollow core slab and dripping onto vehicles. After the affected cores were drained, the leaking cracks were pressure injected using SealBoss 1510 Water Stop Foam.

SealBoss 1510 is a hydrophobic, water-activated polyurethane injection grout designed for leak sealing and water cut-off applications. When the resin encounters moisture, it reacts and expands to form a polyurethane foam within the crack, joint or void.

Its low viscosity helps the resin penetrate tight pathways before reaction, while the SealBoss 15X Accelerator allows the reaction characteristics to be adjusted for the application.

Step 2: Address the Water Entry Path

Stopping the water where it emerged from the slab was only one part of the repair. The exterior cold joint and the affected hollow core cell ends also had to be addressed to reduce continued water intrusion into the slab system. SealBoss 1510 NSF/ANSI 61 Water Stop Foam was therefore injected along the exterior cold joint in areas showing signs of water movement, including efflorescence and rust staining. The affected hollow core cells were also injected approximately 6 inches from the end caps to create a leak-sealing barrier at the suspected entry areas. This approach attacked the problem from both directions:

Seal the pathways where water was escaping and seal the locations where water was entering the hollow core system.

Crack and Joint Injection Using the SealBoss 1-2-3 at 45 Degree Method

The visible leaking areas were injected using the SealBoss 1-2-3 at 45 Degree injection method.

For this project, mechanical injection packers were installed approximately 12 inches from the joint. Approximately 1/2-inch holes were drilled at a 45-degree angle toward the joint so that the drill path would intersect the intended injection area within the concrete. Angled drilling is commonly used in concrete crack injection because it allows the injection point to intersect the crack or joint below the surface rather than relying on drilling directly into the visible opening.

The SealBoss 1-2-3 at 45 Degree method emphasizes:

  • planning and mapping the injection locations,
  • properly drilling and installing the injection packers,
  • injecting the targeted crack or joint thoroughly,
  • and reinjecting as required until adequate material penetration or product refusal is achieved.

Actual packer spacing, drilling geometry and injection procedure must always be adjusted to the conditions of the structure, crack configuration, concrete thickness, water flow and injection material.

On this project, SealBoss 1510 was injected until the targeted joint had accepted sufficient material and the injection response indicated the water-bearing pathway had been filled.

Why SealBoss 1510 Was Used

SealBoss 1510 Water Stop Foam is designed specifically for water cut-off and leak-sealing injection applications.

For this type of repair, several characteristics were particularly useful:

  • Hydrophobic, water-activated polyurethane chemistry
  • Low viscosity for penetration into cracks and water-bearing pathways
  • Adjustable reaction time using SealBoss 15X Accelerator
  • Approximately 30–40 times expansion depending on accelerator concentration and application conditions
  • Semi-flexible reacted foam
  • 100% solids and solvent-free formulation
  • NSF/ANSI 61 drinking-water-contact certification
  • Compatibility with the SealBoss pump, packer and injection equipment system

The material reacts with moisture within the structure, making it well suited to injection into leaking cracks, construction joints and concealed water-bearing voids.

Verification After Injection

The weep holes in the hollow core cells were intentionally left open following the repair.

This provided a simple way to observe whether additional water continued to enter and accumulate in the cells after injection.

Leaving a means of verification was important because successful leak repair involves more than seeing an active drip stop during injection. The repair should also be observed afterward to determine whether the original water pathway has been interrupted.

The building owner was also advised to monitor the affected areas during future wet weather and seasonal thaw conditions.

Correcting the Drainage Condition

Injection addressed the water intrusion through the concrete structure, but the exterior drainage condition also needed attention.

The owner was advised to install drainage boxes or make other appropriate drainage improvements in areas where stormwater collected near the building.

This is an important lesson in leak-sealing work:

Injection can seal a water pathway, but managing the water source can be equally important.

When downspouts, grading or surface drainage continuously direct water toward a structure, correcting those conditions can reduce hydrostatic exposure and help prevent water from finding another route into the building.

A successful waterproofing strategy should therefore consider both the concrete defect and the conditions delivering water to it.

Key Lessons From This Hollow Core Slab Repair

This project demonstrates why hollow core slab leak repair often requires more investigation than simply locating a wet crack.

  • Follow the Water
    The point where water exits the concrete may not be the point where it enters.
  • Investigate the Hollow Cells
    Water can accumulate inside hollow core cells without being visible from the exterior.
  • Check Adjacent Cells
    Finding water in one cell does not automatically mean neighboring cells are dry.
  • Use Inspection Tools When Necessary
    A borescope can provide valuable information about conditions that cannot be seen from the slab surface.
  • Drain Before Sealing When Required
    Removing accumulated water made it possible to better evaluate the affected cells and proceed with the repair.
  • Treat the Entry and Exit Paths
    Sealing only the dripping crack may leave the original water-entry pathway untreated.
  • Look Beyond the Concrete
    Drainage, downspouts, grading and other site conditions can contribute directly to recurring water intrusion.

A System Approach to Hollow Core Slab Leak Repair


The contractor:

  • identified the exterior drainage condition,
    located water trapped inside the hollow core cells,
    drained the affected cells,
    checked adjacent cells,
    used a borescope to investigate the suspected entry area,
    injected the leaking cracks and cold joint,
    sealed the affected hollow core ends,
    and left weep holes available for post-repair observation.

The success of this repair came from treating the leak as a water-management problem rather than simply a visible crack.

Using the SealBoss 1510 Water Stop Foam System together with mechanical injection packers and the SealBoss P2002 injection pump provided the contractor with a complete pressure-injection approach for the water-bearing cracks, joints and hollow core areas encountered on the project.

Important Note on Prestressed Hollow Core Slabs

Hollow core slabs are prestressed structural members. Drilling and repair work should be performed by qualified personnel with an understanding of the slab configuration and prestressing system. Injection hole locations and drilling procedures must be appropriate for the specific structure; the dimensions described in this case study represent this particular project and should not be treated as a universal drilling specification.

Need Help With a Hollow Core Slab Leak?

Water inside hollow core concrete can be difficult to diagnose because the visible leak may tell only part of the story.

SealBoss provides professional polyurethane injection resins, pumps, injection packers, accessories and technical support for concrete leak-sealing and water-stop applications.

For assistance selecting an injection system or evaluating a hollow core slab water-intrusion application, contact a SealBoss technical representative.

Products Used:
Injection Resin: SealBoss 1510 Hydrophobic Water Stop / Leak-Seal Foam w/ 15x Accelerator

Injection Packers: SealBoss 1/2” 13-100 Evolution Aluminum Packers

High Pressure Pump: SealBoss P2002 Single Component Injection Pump

Cleaning Materials: R70 Pump Flush, Xylene, rags, bucket

Additional Tools: 18” x 1/2″ drill bit — 3/8” Crescent Wrench — Dead Blow Hammer
Hammer Drill — Access 110v Power — Vacuum

SealBoss ® 1510 NSF Hollow Core Slab Water Stop Foam:

  • Hollow Core Slab Leak-Seal Repair, Crack & Joint Leak Sealer

SealBoss ® 1510 Hollow Core Concrete Slab Seal Foam Advantages:

  • Low Viscosity
  • Fast Cure Time
  • Advanced and Proven SealBoss ® Product-Pump-Packer System
SealBoss ® Injection Foams to Stop Water


Bestselling SealBoss ® Brand P2002 Injection Pump Advantages

  • Light Weight Injection Pump
  • High Quality Components for Durability
  • Proven Design – Thousands of Units Sold
  • Easy To Clean
  • Easy To Maintain
  • Heavy Duty For Daily Use
  • Pressure Gauge, Hose Set, Hopper Included
  • Recommended For Beginners & Injection Pros
  • > 5000 PSI Injection Pressure Possible

In Person and Video training is available upon request, contact SealBoss today to speak to your regional technical representative on our SealBoss full system solutions and offerings. 

SealBoss ® Injection Pump Systems

 “While providing jobsite assistance, support and training, we create a positive learning environment where confidence and a level of comfort can be achieved in a short period of time allowing for successful repairs to be continued after the training.

From training new companies to new employees, SealBoss has continued to provide support to our users for 36 years.

With a knowledgeable technical support team, we are here to help with any questions you may have”

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Curtain Injection In Pictures

Curtain Injection in Pictures

And Podcast
SealBoss Curtain Injection Pattern

Curtain / Bladder Injection - Curtain Wall Grouting Method

Water intrusion is a persistent challenge for below-grade concrete structures, where traditional patching and surface sealers often fall short. The failures of these surface-applied remedies—such as patches, liquid sealers, and membrane applications—stem from their inability to address the root causes of leaks. These methods provide only temporary relief, leaving structures vulnerable to recurring hydrostatic pressure and ongoing water damage.

Curtain wall grouting, including advanced techniques like curtain and bladder injections, offers a reliable, long-term solution to these challenges. Unlike surface treatments, these methods work by creating a robust waterproof membrane and water barrier behind the structure. This approach not only seals cracks and cold joints from within but also fortifies the structure against future water intrusion.

By injecting specialized grouts through the structure to form a protective layer on the positive side, curtain injection ensures a comprehensive and lasting seal. Whether applied through stage grouting or other targeted injection methods, this professional approach delivers durable protection, minimizing service interruptions and maximizing cost-effectiveness in the long run.

Curtain Injection in Pictures SealBoss

Curtain / Bladder Injection is the Reliable Way to Waterproof Your Below Grade Concrete Structure

Why Patches and Liquid Sealers Often Don’t Stand the Test of Time

Experiencing the frustration of failing patches and paint applications on damp, actively leaking, below-grade structures is something many of us can relate to.

These are typically failed attempts to block hydrostatic water intrusion using surface-applied remedies that serve as temporary solutions at best.

Interior patches and membrane applications, while seemingly addressing the problem, often don’t tackle the root cause and rarely provide a lasting waterproofing resolution.

A Professional Approach to Curtain Injection:

Sealing Cracks Permanently and Establishing a Waterproof Membrane and Water Barrier behind the Structure

Water leakage via cold joints, cracks, and other irregularities in concrete can frequently only be effectively and permanently sealed using advanced injection techniques, such as curtain, bladder, and stage grouting injection methods.

The SealBoss Injection Product offers a professional solution to these issues, filling and sealing the cracks from the inside out. This product is injected through the structure, forming a membrane on the structure’s positive side, thus providing a more effective and lasting waterproofing solution.

The Art of Stage Grouting Technique

In complex grouting scenarios, the stage grouting technique is often the favored approach. This process entails a strategic series of injections carried out in a staged manner, utilizing lower volumes of product in each application.

Each stage of this meticulous process is allowed sufficient time to react, allowing the grout to solidify and establish a natural barrier before proceeding with the subsequent stage of grouting. This carefully phased and controlled deployment not only elevates the overall efficacy of the grouting operation but also ensures thorough and consistent coverage along the exterior of the wall.

Comparative Cost Analysis of Injection Grouting Sealing Methods

Understanding the financial impact of various sealing techniques is essential for making cost-effective decisions. Below is a comparison.

Crack Injection

Direct Costs: Moderate for materials and labor, product is injected directly into the cracks, joints, and voids. Low for equipment.
Indirect Costs: Minimal, as the method is fastest and causes little service interruption.

Curtain Grouting

Direct Costs: Higher for materials and labor, product is injected through the structure into the substrate behind, which results in higher material consumption. Packers are set in distinctive patterns. Moderate for equipment.
Indirect Costs: Higher, due to the lengthier process of preparation and product pumping, which can lead to more significant service disruptions.

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Tunnel Water Stop Injection Leak Repair

Tunnel
Water Stop
Injection
Leak Repair

Tunnel Water Stop Injection Leak Repair

Leak Sealing
Systems

Tunnel Water Stop Injection Leak Repair with Polymer Grout Injection

Introduction:

Tackling Water Leakage in Tunnels: Challenges and Solutions

Water intrusion is a persistent challenge in tunnel infrastructure, affecting safety, durability, and operational efficiency. This article explores the risks associated with water leaks in various tunnel types—utility, vehicle, subway, rail, and pedestrian tunnels—and presents advanced solutions for effective sealing and structural reinforcement.

A key focus is the use of Polymer Injection Grouts, particularly acrylate gels and polyurethane resins, which offer reliable waterproofing and long-term stability. We delve into the properties and applications of these materials, outlining a step-by-step approach to leak diagnosis, material selection, and injection techniques.

Additionally, the article highlights SealBoss’s specialized products designed for underground water ingress repair, emphasizing the critical role of proper training and equipment for successful application. Whether addressing minor seepage or severe structural leaks, this guide provides essential insights for ensuring tunnel integrity and longevity.

Tunnel Water Stop Injection Leak Repair Overview 

Tunnels, essential to modern infrastructure, vary in design and function but share a common challenge—water intrusion. Below is an overview of the tunnel types most susceptible to leaks and the potential risks they face:

  • Utility Tunnels – These tunnels house essential systems such as electrical wiring, water pipes, and gas lines. Water infiltration can lead to pipe corrosion, electrical failures, and even hazardous gas leaks, compromising both safety and service reliability.

  • Vehicle Tunnels – Water seeping through tunnel walls or accumulating on road surfaces creates hazardous driving conditions. Pooled water can reduce tire traction, increasing the risk of skidding, accidents, and severe traffic disruptions.

  • Subway Tunnels – Built beneath densely populated urban areas, subway tunnels are highly vulnerable to leaks from surrounding soil and aging infrastructure. Persistent water intrusion can disrupt train operations, cause service delays, and lead to costly maintenance and repairs.

  • Rail Tunnels – Water intrusion in rail tunnels poses significant risks, particularly to electrical components and track stability. Excess moisture can weaken the track bed, cause rail misalignment, and in extreme cases, contribute to derailments.

  • Pedestrian Tunnels – Water leaks in pedestrian tunnels create slippery surfaces, increasing the risk of slips and falls. Persistent dampness also encourages mold and bacteria growth, leading to poor air quality and potential health hazards.

Waterproofing and leak repair solutions are essential to maintaining tunnel safety, functionality, and longevity. Addressing water intrusion early can prevent costly damage and serious operational disruptions.

How to stop leaks of high hydrostatic pressures with Injection Grouts

Water ingress can cause immediate damages as well as lead to  increased project costs and may lead to many other issues down the line.

Water ingress poses both immediate and long-term challenges, driving up project costs and leading to structural deterioration if left unaddressed.

Leaks through cracks, joints, and voids can be effectively sealed using advanced injection systems that employ cost-efficient and highly reliable chemical grouts, such as multi-component acrylate gels and single-component polyurethane resins.

When properly engineered, resin injection systems do more than just stop leaks—they also stabilize surrounding soil by transforming loose sands into a firm, sandstone-like consistency and consolidating gravel into a bonded, load-bearing structure. This not only enhances the durability of the tunnel but also improves its overall resilience against future water intrusion.

Example: SealBoss Acrylates Used to Seal Leaks in Tunnel

What are Acrylate Gels?

Acrylate gels, also known as acrylic gels, are highly flexible, ultra-low viscosity, hydrophilic sealing agents designed for non-structural injections. With a consistency similar to water, they effectively penetrate cracks, joints, and voids, making them ideal for grid, curtain, and bladder injection applications, as well as use in injection tube sealing systems.

Thanks to their exceptionally low viscosity and surface tension, polyacrylate gels offer superior penetration capabilities, allowing them to reach even the smallest fissures. Their adjustable gel time enables precise application, adapting to varying job site conditions such as temperature and injection distance.

When in contact with water, acrylic gels expand hydrophilically, creating a compression seal that prevents further leakage. This swelling behavior makes them an effective solution for waterproofing applications. Additionally, acrylate injection equipment can be easily cleaned with water, simplifying maintenance.

SealBoss provides a comprehensive range of high-performance products designed to control water ingress in underground mining operations, tunnels, and other commercial structures facing leakage challenges. Our solutions support waterproofing, soil consolidation, crack and joint repair, sealing, bonding, and cavity filling, ensuring durable and long-lasting protection.

Tunnel Water Stop Injection Leak Repair

How to Start Acrylate Injection Leak Sealing Injection Repairs

The principal steps to solve a problem are:

  • Diagnosis of the problem
  • Specification of injection methods
  • The correct choice of resin, pumps, packers and accessories
  • Training of installation personnel, a well trained and experienced team is paramount

Will I need more than One Product?

That depends on the conditions of the jobsite. Polyurethane and Acrylate injection systems offer a variety of solutions to problems found in geotechnical applications,  in tunneling, waterproofing underground works and civil engineering in general. While there is no single resin that will suit all conditions, the correct resin must be used to achieve the best results possible and to meet the requirements of the specification.  

If there are any questions about the various chemical grouts available, please do not hesitate to contact us, we are here to assist in any way we can. Always remember to work safely by wearing eye protection and gloves when handling any type of chemical systems.

Which products are shown in the videos?
Products used for Tunnel Water Stop Injection Leak Repair
SealBoss 2400 A1
SealBoss 2400 A2
SEALBOSS-2400-B-SMALL
SealBoss 2400 B
IP2C-2G 3 component acrylate gel pump
SealBoss IP2C
Stainless Steel Gel Pump

Related Article

Call Your SealBoss Technician

If you have any questions on crack injection water stop procedures or any injection related applications, please contact our team of qualified SealBoss representatives to schedule an on site consultation & full injection systems training. Call us at 714-662-4445.

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Efflorescence and Leaks

Efflorescence and Leaks

Efflorescence – Indicator of Water Problems in Structures

Efflorescence, at first glance, may seem like a simple aesthetic issue. It presents itself as a white or occasionally vibrant and colorful, chalky residue on walls, especially around cracks and joints. This substance can evolve, often resembling delicate, hair-like filaments. Yet, beyond its surface appearance, efflorescence strongly signals the presence of a water leak.

A crack with efflorescence built-up has to be considered a leaking crack.

What exactly is efflorescence?
Efflorescence is the result of a variety compounds that have been dissolved and transported by water. When this water reaches the surface of materials like concrete or masonry, it evaporates, leaving behind minerals, metals and inorganic compounds, such as calcium hydroxide which interacts with atmospheric carbon dioxide to form fine calcium carbonate crystals.

The result is the characteristic residue which is mostly greyish or white. However, it can sometimes appear colorful if the water causing the efflorescence contains minerals or compounds that produce colors when they crystallize. Copper salts often yield blue or green efflorescence. Similarly, iron salts can lead to yellow, brown, or reddish hues, while manganese can give rise to pink or purple shades.

The presence of these or other metal ions in the water can lead to colorful efflorescence. These ions may come from the soil, water supply, or even from the building materials themselves. Therefore, colorful efflorescence not only indicates a moisture issue but could also point to the presence of specific minerals or contaminants in the environment.-

While efflorescence itself might not be harmful, it is a beacon signaling a potential moisture problem. As water continues to seep into building materials, it does not just evaporate from the surface. The moisture can be absorbed deeper into the material, leading to a process known as wicking. Over time, this persistent moisture can compromise the structural integrity of the building materials.

For inspectors and concrete repair contractors alike, recognizing efflorescence is crucial. It is not just about identifying a water leak; it is about understanding the capillary forces at play and the distribution of water within the structure that will cause the damage. By educating their clients about efflorescence, inspectors can provide valuable insights into potential problems that already may exist, even when the structure appears to be dry on the outside.

In summary, efflorescence is an indicator for  moisture problems in a structure, even when it appears to be dry at the time of inspection. It forms when water with dissolved salts evaporates from concrete or masonry surfaces, leaving a white, greyish or even colorful residue. It is a a clear signal of deeper moisture problems, past and present, that can have long-term implications for the structural health of a building.

When it comes to polymer crack injection and structural repairs, understanding and addressing the root causes of efflorescence is essential.

Efflorescence and leaks 1
Efflorescence and leaks SealBoss
Efflorescence and leaks 1
Efflorescence and leaks 3

Efflorescence and Crack Injection Repair
A Case Study at International Airport's Reservoir

Efflorescence and leaks SealBoss
Efflorescence and leaks 3

Introduction

We know that efflorescence is a clear indicator of moisture issues within a structure. Its presence can signify past leakage, even when the surface appears dry. Addressing efflorescence build-up and active leaks can be crucial for the longevity of concrete structures.

This short case study highlights a repair project at an International Airport, highlighting the solutions in association with efflorescence and crack injection repair.

Project Overview

The Reservoir spillway structure at the International Airport required significant restoration and rehabilitation. The contractor was tasked with chemical grouting as part of this extensive project. The objective was to clean up all compromised concrete, crack inject all areas of present and past water leakage, patch it, and re-caulk all cold joints.

Identifying the Problem

Visible water infiltration and signs of efflorescence on cracks and joints were the primary concerns. Efflorescence around cracks and joints indicates past leakage, even in the absence of active water seepage at the time of inspection, and needs to be addressed.

The source of water intrusion was identified as rain runoff, which led to the oversaturation of the built-up and back-filled sections adjacent to the spillway walls.

Proposed Solution

SealBoss solves efflorescence and leak problems by stopping the water at its source with targeted polyurethane injection and curtain-grouting systems.

For active or gushing leaks, SealBoss 1510 Water Stop Foam is injected to expand on contact with water and cut off flow; for tight, hairline cracks and cold joints, SealBoss 1570 / 1570 LV low-viscosity foams penetrate fine fissures to create a durable, watertight barrier.

Where moisture migrates through larger surface areas, SealBoss FlexGel hydrophilic gel can be used for curtain injection to form a flexible waterproof membrane behind the substrate, often in combination with hydrophobic foams for optimal results.

Reaction time and expansion are tuned with 15X Accelerator to match site conditions, and SealBoss Seal Oakum can be resin-saturated to pre-pack tie holes or voids under flow.

This integrated approach halts capillary water movement—the root cause of efflorescence—while minimizing recurrence and preserving structural integrity; the 1510 system is even NSF/ANSI 61 certified for potable-water contact where required.

The engineer recommended injecting the affected cracks and joints with a moisture-activated hydrophobic foam

The SealBoss Injection Foam System is specifically designed to address such areas showing signs of efflorescence and visible water infiltration.

Execution

Custom scaffolding was erected to facilitate the repair process. The contractor’s certified crew utilized the SealBoss P2002, a portable high-pressure injection system capable of overcoming the hydrostatic and physical resistance forces within the wall,  displacing moisture, and injecting the SealBoss 1510 Water Stop and Leak Seal Foam at the appropriate pressure and volume. Given that the concrete wall was approximately 12 inches thick, the SealBoss 13-100AL Evolution Packers were strategically installed by drilling directly into the cracks.

This approach was chosen based on the concrete’s quality to minimize the risk of spalling due to injection pressures. Each packer was reinjected as deemed necessary to ensure a comprehensive and durable seal. In many instances, the injected material traveled through honeycombed concrete, reaching areas several feet away from the injection point.

Whenever this happened, the injection was paused until the material reached a state of cure to ensured that subsequent injections would follow a new path of lesser resistance within the crack structure’s capillaries.

Results

The injection crew successfully halted the water intrusion well within the specified time frame. This efficiency meant that the reservoir could return to its regular levels much quicker than initially anticipated.

Note

As water may find its way to areas beyond the initial injection repair, there might be a future necessity for spot treatments in previously dry regions.

Conclusion

Efflorescence around cracks and joints, is a clear indicator of leakage, even if dry durning inspection. It often is a telltale sign of deeper structural problems.

The Reservoir project at the International Airport serves as a testament to the importance of timely intervention and the use of advanced techniques like crack injection repair. By understanding and addressing the root causes of efflorescence and water intrusion, structures can be preserved and protected for the long term.

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Versatile Injection Grout SealBoss 1510

SealBoss 1510

Versatile Injection Grout Podcast

SealBoss 1510 Features Summarized in a 5 Minute Overview

 

Podcast Transcript

Okay, let’s unpack this. You know, imagine maybe a historic building standing firm despite relentless groundwater. Or maybe a subway tunnel where not a single drop seeps through. Ever wondered how critical challenges like persistent water leaks in concrete or maybe unstable soil beneath massive structures are actually tackled? Today, we’re taking a deep dive into a powerful, often unseen solution that really gets into the structure of our world. Our mission then is to explore what’s widely considered the most versatile injection grout out there: SealBoss 1510. You might also know it as Water Stop Foam.

Yeah, that’s right. And it’s not just any product. It’s a flagship for a reason. It’s specifically engineered for professional use across a really surprising and vital range of applications. It’s one of those silent heroes, really.

Okay, so let’s get into the nitty-gritty then. What is this water foam? Is it like the spray foam insulation you might use in your attic, or something else entirely?

That’s a great question. They’re both foams, yes, but very different chemistry and purpose. SealBoss 1510 is actually a specialized liquid sealant first. We call it hydrophobic, which basically just means it repels water—it actively pushes it away. And critically, it’s water-activated. The moment it hits water—bang!—it kicks off a chemical reaction, okay?

It expands, forming this dense, impermeable foam. It’s based on MDI polyurethane. That’s a really robust polymer, very durable. Plus, it’s formulated to be 100% solvent-free and 100% solids. Very pure, very potent stuff. And when you mix it with its 15X accelerator additive—well, that one is really designed to cut off flowing water almost instantly.

Yeah. Hold on, 40 times expansion? Did I hear that right? That sounds huge.

You did—40 times. It’s pretty astounding.

So, you could fill up massive voids with just a tiny amount of product. That seems incredibly efficient.

Exactly. That huge expansion factor isn’t just for show. It’s a total game-changer for efficiency on-site. It means you can tackle really big voids and high-volume leaks with surprisingly little material. It makes jobs faster, more effective, and ultimately saves costs.

Makes sense.

And beyond that, here’s where its credentials really make a difference. It’s NSF/ANSI 61 certified for drinking water contact.

Okay, that sounds important. NSF/ANSI 61. What does that actually mean in practice for where it can be used?

Oh, it’s absolutely vital. That certification means it’s proven safe to use in critical drinking water infrastructure. Think reservoirs, water treatment plants, the pipes carrying water to your tap, right?

It guarantees no harmful stuff leaches into the water supply. That’s a huge differentiator, something generic products just can’t claim.

Oh, I see.

And just on a practical note, it’s even unregulated for transport, which might sound minor, but it really simplifies getting it to job sites, especially tricky ones.

That’s a lot packed into one product for stopping leaks.

Yeah.

So, thinking about concrete leaks specifically, what kind of cracks are we talking about? Does it work for absolutely everything?

Well, for most crack injection scenarios in concrete, this foam is definitely the go-to. It’s incredibly versatile. It handles everything from tiny hairline cracks you can barely see all the way up to gaps about 3/4 of an inch wide.

Okay, 3/4 inch. So, what if it’s wider than that? A really big gap?

Yeah. For those wider, more challenging ones, there’s the oakum method, sometimes called the oakum rope method. It involves soaking a special fibrous rope, oakum, in the 1510 liquid and then packing that soaked rope into the larger crack.

The foam then expands in and around the oakum, creating this really robust composite seal. Very strong, very long-lasting.

Right. Got it. You mentioned versatility earlier, and I’m really struck by how far its uses go beyond just filling cracks. What else can this stuff do?

Oh yeah, its applications really do extend significantly beyond just simple crack repair. If you look at the bigger picture, yes—general leak sealing, concrete repair—but also vital void filling. That’s a big one. For instance, injecting it underneath concrete slabs. Imagine a sinking driveway or maybe a warehouse floor that needs lifting or stabilizing. That’s often called blanket injection.

The foam spreads out horizontally like a blanket, creating a solid support layer underneath.

Okay, blanket injection.

Or say you have water constantly seeping through a basement wall; you can inject the 1510 behind the wall itself. It creates this impermeable curtain or bladder of foam back there. Stops the water before it even gets to the concrete. That’s curtain injection.

Curtain injection. Wow. And I definitely saw something about soil stabilization, too. That sounds like a completely different field of engineering almost.

It really is. And it just shows the material’s adaptability. If you use just a low percentage of that 15X accelerator, the reaction changes. The material’s properties shift, and it becomes this highly effective soil stabilization grout.

How does that work?

It basically permeates into loose soil or pockets of gravel deep underground. Then it expands and hardens, binding everything together. Turns unstable ground into a solid, cohesive mass.

Incredible.

Which makes it super valuable for really challenging geotechnical projects. Things like supporting deep excavations, keeping tunnels stable while boring, strengthening the ground. It prevents collapses, keeps things safe. It truly shows the breadth of it, you know, from sealing a tiny leak to basically fortifying sections of the earth.

So, what does this all mean for you listening in? Well, next time you walk past a construction site, see a newly stabilized building foundation, or maybe just notice your own basement is miraculously dry after a downpour, you’ll know there could be a highly specialized material, something like SealBoss 1510, working unseen, solving these complex problems that quietly keep our world structurally sound and running smoothly.

Absolutely. It just highlights how these specific advancements in material science really underpin the safety, stability, and longevity of everything we build—often without us even realizing the complex solutions involved. So maybe think about this: what stands out to you about the unseen materials, the hidden technologies that make our everyday environment work?

Dam Spillway Leak Sealed

Dam Spillway Leak Sealed

SealBoss 1510 Polyurethane Foam

SealBoss 1510 Leak Sealing Application

What is the Purpose of a Spillway in Dams?

A spillway serves a critical function in dam systems. Either incorporated into the dam’s structure or built adjacent to it, a spillway facilitates the controlled and secure discharge of surplus water downstream.

Introduction

Spillways play a critical role in safely managing excess water in dam systems. Over time, leaks can develop in cold joints and cracks, posing structural risks and operational challenges. Traditional repair methods often fall short—especially under high water pressure.

SealBoss 1510 Water Stop Foam offers a reliable solution. Its hydro-active, expanding polyurethane formula penetrates deep into leaking areas, sealing active water flow and forming a durable, watertight barrier. This article highlights a successful spillway leak repair using Water Stop Foam, demonstrating its effectiveness where other methods failed.

SB 1510 Polyurethane Foam in Dam and Spillway Leak Sealing

Dam Spillway Leak Sealed with Advanced Polyurethane Foam Injection

When it comes to critical infrastructure, few challenges are more pressing than water intrusion in dams. One of the most effective solutions available today is SealBoss 1510 Water Stop Foam, a high-performance, hydro-active polyurethane product. This case study and technical overview demonstrate how a dam spillway leak was sealed using SB 1510 polyurethane foam, offering a lasting and economical solution.

Why Polyurethane Foam for Dam and Spillway Leak Repairs?

Polyurethane foam is widely respected for its low viscosity and superior adhesive properties, making it ideal for sealing active water leaks in dam and spillway structures. Its hydro-reactive nature enables it to expand on contact with water, effectively filling cracks, joints, and voids — even under high-pressure flow.

When injected into a leaking dam or spillway, the foam penetrates deeply into fissures and gaps. It reacts quickly with water, expands, and cures into a solid, waterproof barrier. This process forms a robust seal that prevents further water ingress and strengthens the surrounding substrate.

How Dam Spillway Leaks Are Sealed Using SealBoss 1510

The leak remediation process begins with drilling holes along the affected cold joints or cracks in the dam spillway. Mechanical injection packers are then installed, allowing SealBoss 1510 to be injected precisely where needed. The foam expands rapidly within the concrete structure, bonding to the substrate and stopping the leak at its source.

After curing, the foam forms a permanent repair that is resilient, flexible, and capable of withstanding ongoing hydrostatic pressure—making it one of the best solutions when a dam spillway leak must be sealed quickly and reliably.

Case Study: Dam Spillway Leak Sealed After Multiple Failed Repairs

Background: Persistent Cold Joint Leak

SealBoss was contracted to repair a leaking cold joint in a dam spillway—one that had already failed four previous repair attempts. Prior caulking had eroded due to continuous water pressure, allowing active leakage through the “V” notched joint. With increasing water infiltration, the situation called for a proven, robust method to get the dam spillway leak sealed once and for all.

Step-by-Step: Leak Sealing with SB 1510 Water Stop Foam

  • Surface Prep and Joint Access
    Technicians began by removing loose and deteriorated caulking to fully expose the leaking joint. Drill holes were made adjacent to the joint, and active water flow confirmed correct placement.

  • Oakum Soakum Technique
    To immediately address the gushing leak, the team applied the Oakum Soakum method using SealBoss 1500 Seal Oakum saturated with SealBoss 1510 and accelerated with 15x Accelerator for fast reaction and curing. The oakum was placed directly into leaking crevices to form an initial water block.

  • Injection Packer Installation
    Next, 13-100 AL mechanical packers were installed in a staggered vertical pattern, based on SealBoss’s 1 – 2 – 3, 45 – Degree Injection Guidelines. Strategic spacing ensured coverage while avoiding rebar interference.

  • Polyurethane Injection
    Using the SealBoss P2002 injection pump, catalyzed SB 1510 foam was injected starting from the lowest packer. Controlled pauses allowed the resin to expand fully, minimizing waste while maximizing penetration.

Result: Dam Spillway Leak Sealed with Lasting Effect

All leaking joints were successfully sealed. The high-pressure, active leaks were stopped effectively, and the structure’s integrity was restored. This application proved once again that SealBoss 1510 polyurethane foam is a powerful tool in dam and spillway leak sealing.

Conclusion

If you’re facing persistent water intrusion, cracks, or joint failures in spillway structures, getting the dam spillway leak sealed properly is critical.

The SealBoss 1510 Water Stop Foam injection system provides a fast, durable, and cost-effective repair method—even under high-flow conditions.

This proven technology not only stops active leaks but also extends the life of dam infrastructure. As this case study demonstrates, polyurethane grout injection is the gold standard for dam and spillway maintenance.

Ready to get your dam spillway leak sealed?
Contact SealBoss today at 714-662-4445 or visit our website to connect with an expert and find the right solution for your project.

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Dam Erosion and Sediment

Dam
Erosion and Sediment

Dam Erosion and Sedimentation Control
with Polyurethane Grout Injection Systems

Dam Erosion and Sedimentation Control with Polyurethane Grout Injection Systems

Introduction:

Dam erosion and sediment accumulation in dams present significant challenges, threatening their structural integrity and operational efficiency. Polyurethane grout emerges as an innovative, durable, and versatile solution to effectively address these critical issues. This article explores the advantages of polyurethane grout in managing erosion, sedimentation, and leak control, highlighting its essential role in ensuring the long-term safety and performance of dams.

Polyurethane Grout for Dam Erosion, Sediment, and Leak Control

Understanding Dam Erosion and Sediment Accumulation

Erosion occurs naturally as water infiltrates dams through cracks, joints, and fissures, gradually weakening concrete and soil structures. Additionally, incoming water carries sediment —soil, sand, gravel— which accumulates behind dams, significantly reducing reservoir capacity and placing increased structural stress on dam infrastructure.

Impacts of Erosion and Sedimentation

Structural Risks
Erosion compromises dam stability, potentially leading to structural failure. Sediment build-up exerts additional pressure on dam structures and impedes water flow.

Reduced Operational Efficiency
Sediment accumulation diminishes water storage capacity, adversely affecting flood control, hydroelectric power generation, irrigation, and drinking water supply.

Environmental Concerns and Safeguards

The environmental implications of dam leaks can be significant. Accumulated sediments disrupt downstream ecosystems and water quality, harming aquatic life and ecosystems by altering natural sediment flows and introducing contaminants. Leaks may carry contaminants into natural waterways. SealBoss Water Stop Systems featuring NSF-Certified Polyurethane Grouts can offer an environmentally safe solution for leak sealing, contributing to environmental sustainability.

Polyurethane Grout: A Robust Solution for Dam Erosion and Sedimentation

Polyurethane grout offers an effective, adaptable solution to combat erosion and sediment-related issues, significantly surpassing traditional methods. Its inherent flexibility allows it to accommodate the dam’s natural movements, maintaining a strong, watertight seal over time.

Benefits of Polyurethane Grout in Dam Applications

  • Versatility:
    Suitable for concrete and earth dams, polyurethane grout is effective in crack injection, soil stabilization, permeation grouting, and sediment barrier formation.
  • Rapid Curing and Reduced Downtime:
    Quick curing and hydro-active properties minimize operational interruptions, crucial for essential infrastructures such as hydroelectric power plants and water supply dams.
  • Economic Advantages:
    Polyurethane grout’s long-term durability reduces maintenance costs, and rapid curing times help maintain continuous energy production, offering substantial cost savings.

Advanced Solutions from SealBoss for Dam Erosion and Sediment Control

SealBoss polyurethane grout injection systems deliver precise, reliable erosion control, leak sealing, and sediment management. Key applications include:

  • Polyurethane Soil Stabilization:
    Injecting polyurethane resins stabilizes surrounding soils, mitigating erosion and preventing sediment influx.
  • Leak Sealing and Void Filling:
    SealBoss products effectively address leaks and fill voids, reinforcing dam infrastructure and preventing further erosion and sediment-related damage.
  • Structural Reinforcement:
    Polyurethane injection significantly enhances the structural integrity of dam walls and spillways, extending infrastructure lifespan and reliability.

Energy Efficiency and Environmental Protection

Leaks and erosion negatively impact dams’ energy generation potential. By sealing these vulnerabilities with polyurethane grout, dams maintain maximum energy output and protect against environmental harm, offering an environmentally safe, NSF-certified solution.

Best Practices for Effective Dam Maintenance

Dam owners and operators should adopt proactive strategies, including:

  • Comprehensive Inspection:
    Regularly inspect and monitor for erosion and sediment issues.
  • Expert Consultation:
    Engage specialists experienced in dam infrastructure.
  • Quality Materials:
    Use high-quality polyurethane grout from reputable suppliers.
  • Professional Implementation:
     Contract skilled professionals familiar with polyurethane grout applications.
  • Ongoing Monitoring:
    Continuously assess effectiveness post-repair to ensure sustained performance.

Contact SealBoss for Expert Assistance

With decades of expertise in polyurethane grout technology, SealBoss offers specialized recommendations and connects you with experienced contractors skilled in dam repairs, including crack and joint sealing, curtain wall grouting, permeation and consolidation grouting, and injection waterproofing techniques.

Conclusion

Polyurethane grout injection systems present a comprehensive, durable, and economically viable solution to erosion, sediment accumulation, and leakage challenges in dams. Its versatility and effectiveness ensure long-term dam safety, structural integrity, operational efficiency, and environmental sustainability.

Call to Action

Enhance your dam’s safety and efficiency with SealBoss polyurethane grout solutions. Contact us at 714-662-4445 or via our Contact Form for tailored, expert-driven support in maintaining your dam’s integrity.

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Watertight Pipe Penetration Sealing

Watertight Pipe Penetration Sealing

Guidelines for Pipe Penetration Waterproofing

Introduction

Waterproofing pipe penetrations is a critical task in maintaining the integrity of a structure housing utility systems. Ensuring that pipes and conduits passing through walls or floors do not allow water ingress is essential for preventing damage and maintaining safety, especially in environments with high moisture or any water exposure. This guide provides a comprehensive overview of the steps and techniques necessary for effective pipe penetration waterproofing and sealing.

It covers the basics of installing new or replacing failed water stops around existing pipe penetrations, utilizing a range of products and techniques to seal these areas effectively. Whether you are dealing with active leaks, dormant leaks, or the unwanted migration of pollutants or gases such as exhaust fumes, unsealed pipe penetrations and conduits require an understanding of the best sealing procedures for your specific situation, this guide, along with the expert assistance of SealBoss technicians, offers the knowledge and solutions needed to address these challenges confidently.

How to Replace failed Water Stop around existing Pipe Penetrations

Step 1: Clean the area – Begin by eliminating any old grout or deteriorated concrete from around the pipe penetrations. Ideally, remove material to a depth of at least 1″ and a width of 1/2″ all around the pipe’s circumference. In this demonstration, an air chisel was utilized adhering to the safety protocols outlined by the natural gas plant.

Step 2: Clear the debris – After the removal of old grout or concrete, it’s essential to thoroughly clean the area. Employ a brush, air blower, or vacuum cleaner to eliminate any remaining dust or loose particles.

Step 3: Initiate the repair process – Once the area is clean, you’re ready to proceed with the installation of the repair products. Your pipeline is now prepped for the restoration process to commence.

Utilizing Multiple Products and Techniques for Pipe Penetration Sealing

Oakum Saturation with Foam Grout

Oakum Soakum Installation

The process starts by unwinding and snipping an adequate length of Oakum rope to encircle the part of the pipe where it breaches the wall. The installer will initially manipulate and expand the Oakum, augmenting its surface area for better adherence with the catalyzed resin.

Next, using a zip-top bag or a bucket, dispense a sufficient quantity of SealBoss 1510/1570 resin to comprehensively saturate the Oakum strand. Following this, add the desired 15x catalyst concentration of 5% – 20%, contingent on the intensity of the leak.

The catalyst ratio dictates the reaction time and expansion rate. For dormant leaks, we recommend a catalyst percentage of 5% to 10%, and for active leaks, a proportion of 10% to 20% is suggested. Our technical representatives are available for any queries related to catalyst ratios.

After thoroughly soaking the Oakum, swiftly wrap it around the pipe, manipulating the fibers to fill as much of the pipe penetration annulus as possible. This forms a gasket-like sleeve around the pipe. Spray the soaked Oakum with water to facilitate the foam’s catalyzation. Within moments, you’ll observe the foam starting to form and expand.

Upon the foam’s complete curing, consider the repair concluded successfully.

  • In areas of constant hydrostatic pressures it is often recommended to inject the circumferential void throughout the thickness of the wall using SealBoss 1510 or 1570 Water Stop Foam.
  • With the use of a SealBoss Grout Injection Needle and a low cost HP1500 Ultra Light Hand Gun or a HP 100 Hand Pump, the foam grout can be conveniently placed and injected into the void. Depending on the conditions at the jobsite, the injection can be performed following the ‘Oakum Soakum Procedure’, by penetrating the initial repair with the injection needle and inject SealBoss Water Stop Foam behind it.
  • For small jobs and pipe diameters, and for low cost applications where hand pump and injection needles are not feasible, SealBoss Can-Seal Foam can be used as a lower grade alternative.

Upon completion of the leak-sealing application, carefully remove any surplus cured foam protruding from the annulus to ensure a clean working area for the subsequent application of grout or mortar around the pipe penetration.

  • SealBoss SwellCaulk is a premium, single-component hydroactive sealant, specifically designed to expand upon contact with water, thereby creating a secure, watertight seal. This product is especially effective for repairing pipe and cable penetrations. For optimal results with SwellCaulk, apply a bead of an appropriate size around the pipe, extending it beyond the chipped area and up to two inches deep into the circumferential void. Upon exposure to moisture, this hydrophilic material initiates its expansion process, thereby effectively forming a watertight seal around the pipe.

Pipe Penetration Sealing Products

Which Pipe Sealing Procedure is Right for You?
Call Your SealBoss Technician

Should you have any inquiries regarding pipe penetration sealing, crack injection water stop methodologies, or any other injection-related procedures, do not hesitate to reach out to our team of proficient SealBoss representatives. We are more than happy to assist you.

In order to assist you in understanding our systems more effectively, we provide on-site visits along with practical, hands-on training sessions involving our injection systems.

Call us at 714-662-4445.

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Cold Joint Injection

Cold Joint Injection

Leaking Cold Joints Sealed

Cold Joints in Concrete Structures and the Polyurethane Polymer Solution

Introduction

Concrete is a versatile and strong material that plays a key role in modern construction, but it comes with certain challenges. One common issue is the formation of cold joints — visible lines or separations that occur when new concrete is poured against concrete that has already begun to set. These joints can compromise the structural integrity, creating weak points that are vulnerable to water infiltration, leaks, and long-term damage. Proper identification and repair of cold joints are essential for maintaining the durability and performance of any concrete structure.

Cold Joint Injection: Permanent Solutions for Concrete Leaks and Structural Integrity

 

Concrete is one of the most widely used building materials in the world due to its strength, versatility, and durability. However, like all materials, concrete has vulnerabilities. One of the most common and potentially damaging issues in concrete construction is the formation of cold joints. These unplanned discontinuities in concrete can significantly impact the long-term integrity of structures, particularly when they become pathways for water infiltration.

Fortunately, cold joint injection using advanced polyurethane polymers offers an effective and lasting solution. This article will explore what cold joints are, why they occur, the risks they pose, and how cold joint injection provides a reliable fix for both residential and commercial construction projects.

What are Cold Joints?

A cold joint forms when freshly poured concrete is placed next to or on top of concrete that has already started to set. Rather than bonding as one cohesive mass, the two layers remain separated by a visible and structural boundary. This boundary lacks proper adhesion and can act as a weak point in the structure.

Cold joints typically occur due to:

  • Delays in pouring concrete batches

  • Interruptions in concrete delivery or placement

  • Temperature variations that cause uneven curing

  • Scheduling issues or construction mistakes

The result is a distinct line or seam in the concrete that appears harmless at first but can lead to serious problems over time. Cold joints are particularly vulnerable to water infiltration, which can trigger internal corrosion of rebar, cause freeze-thaw damage, and reduce the overall life expectancy of the structure.

Cold Joint Injection: The Polyurethane Polymer Foam Solution

The most effective way to repair and seal cold joints is through a process called cold joint injection, using high-performance polyurethane injection resins. This method restores the integrity of the concrete joint and creates a watertight barrier that prevents future leaks.

Why Use Polyurethane for Cold Joint Injection?

Polyurethane injection resins are hydrophobic or hydrophilic foams that expand upon contact with moisture, filling voids and cracks with precision. When injected into a cold joint, the resin reacts with any water present, forming a flexible yet durable foam that bonds tightly to the surrounding concrete.

Benefits of polyurethane cold joint injection include:

  • Expands to fill cracks and voids – Ensures complete coverage and sealing

  • Forms a watertight barrier – Prevents water infiltration and leak recurrence

  • Flexible and durable – Adapts to slight movements and temperature changes

  • Non-invasive – No need for major demolition or reconstruction

  • Fast-curing – Rapid installation and reduced downtime

Step-by-Step Cold Joint Injection Process

The cold joint injection procedure typically involves the following steps:

  1. Inspection and Assessment
    The area is assessed to determine the severity of leaks, substrate condition, and appropriate injection points.

  2. Drilling and Packer Installation
    Holes are drilled at specific intervals along the cold joint. Mechanical injection packers are inserted to allow precise resin delivery under pressure.

  3. Injection of Polyurethane Resin
    Using a high-pressure injection pump, the polyurethane resin is injected into the packers. As it travels into the joint, the resin reacts with moisture, expanding and filling all voids and cracks.

  4. Sealing and Curing
    Once the injection is complete, the resin cures quickly, forming a flexible, watertight seal. Packers are then removed and holes patched.

  5. Final Inspection
    The site is checked to ensure the leak has been completely sealed and no further moisture intrusion occurs.

Real-World Application: SealBoss Cold Joint Injection in Kansas City

A recent project in Kansas City demonstrated the effectiveness of SealBoss’s cold joint injection system. A structure with both vertical and horizontal cold joints had developed active leaks due to a failed pre-existing waterproofing system.

SealBoss’s Regional Sales Manager provided on-site support and training during the injection process. The contractor drilled injection holes and installed ½” mechanical packers for a secure fit. Based on site conditions, both angled and direct drill placements were used.

The team injected SealBoss 1510 polyurethane resin using the P2002 high-pressure single-component injection pump. Due to the low substrate temperatures, the resin was catalyzed with 15% SealBoss 15X High Foaming Accelerator, which ensured rapid and effective expansion. The result? All active leaks were sealed successfully, and the structure’s cold joints were permanently reinforced.

Advantages of SealBoss Cold Joint Injection Systems

SealBoss offers industry-leading cold joint injection materials and equipment designed for professional contractors and infrastructure repair specialists. Key advantages include:

  • Complete waterproofing solutions for cold joints, cracks, and voids

  • High-performance resins that expand even in low temperatures

  • Specialized pumps and packers for efficient delivery

  • On-site technical support and training

  • Trusted by contractors worldwide in demanding applications

Whether repairing parking garages, basements, retaining walls, or tunnels, SealBoss systems deliver reliable, long-term protection against water intrusion and structural decay.

Cold Joint Injection: An Investment in Longevity

Repairing cold joints with polyurethane injection is not just a short-term fix—it is a long-term investment in structural performance. By addressing water infiltration early and effectively, property owners and contractors can prevent costly repairs, ensure code compliance, and extend the service life of critical structures.

For engineers, architects, and maintenance professionals, understanding the value of cold joint injection is key to preserving the quality of concrete infrastructure.

Contact SealBoss for Expert Cold Joint Solutions

SealBoss is a global leader in leak sealing, structural repair, and concrete protection technologies. If your project involves water leaks, cracks, or cold joints, contact our team for expert guidance, high-performance products, and technical support tailored to your needs.

SealBoss delivers on-site training and specialized technical assistance for tackling cold joint leaks, as well as other concrete structure issues.

Considering a Solution for Sealing Cold Joints During Construction?

Look no further! We not only offer systems specifically designed for sealing cold joints but also provide expert advice to prevent moisture issues right from the construction stage.

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Please don’t hesitate to call us at 714-662-4445 with any questions, or request to be contacted here, we look forward to helping you find a solution. On-site support from knowledgeable and experienced technical reps is available upon request.

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How to Seal Shrinkage Cracks

How to Seal Shrinkage Cracks

How to seal Shrinkage Cracks

Shrinkage Cracks Sealed at Wastewater Treatment Plant

Introduction:

In wastewater treatment plants, maintaining the integrity of concrete structures is crucial for safe and efficient operations. Shrinkage cracks, especially around pipe penetrations, are common but problematic, leading to water infiltration, contamination risks, and structural deterioration. These cracks compromise the durability and safety of facilities, resulting in increased maintenance costs and potential environmental hazards.

Addressing shrinkage cracks requires specialized solutions that comply with stringent safety standards, particularly for structures in contact with potable water. SealBoss’s advanced polyurethane injection systems are designed to effectively seal these cracks, preventing water seepage and ensuring long-term structural integrity. By forming a closed-cell foam upon contact with water, these systems provide a durable barrier against leaks and contaminants.

This article explores the causes of shrinkage cracks, their implications for wastewater infrastructure, and innovative NSF-certified sealing methods that enhance durability and operational safety.

Understanding Shrinkage Cracks in Concrete

What are Shrinkage Cracks?

Shrinkage cracks are a natural occurrence in concrete structures that form during the curing and drying process. Concrete, a blend of cement, aggregate, and water, undergoes a volume reduction, or shrinkage, as the water used in the mix evaporates. This process of evaporation causes the concrete mass to shrink and contract.

Simultaneously, the internal reinforcements or sub-bases that the concrete is poured onto restrict this shrinkage. This restriction generates tensile stresses within the concrete. When these stresses exceed the concrete’s tensile strength, they give rise to drying and shrinkage-related cracks.

Shrinkage cracks, although often very small, are of significant concern in certain structures. Even though they typically don’t compromise the structural integrity of the concrete, they can create pathways for water and other corrosive materials. This is particularly crucial in structures like dams, where minor leaks can have substantial implications.

Moreover, it’s important to note that the shrinkage of concrete and the subsequent development of cracks is an irreversible process. Therefore, any resulting water leakage needs to be addressed with suitable methods such as concrete crack injection.

SEALBOSS SHRINKAGE CRACK INJECTION
Setting Packers
SEALBOSS SHRINKAGE CRACK INJECTION
Marking Cracks
SEALBOSS SHRINKAGE CRACK INJECTION
Injecting SB 1510
SEALBOSS SHRINKAGE CRACK INJECTION
Excellent Penetration

Effective Sealing of Shrinkage Cracks at a Wastewater Treatment Plant

Scope

At the wastewater treatment plant in Salina, Kansas, leaks were detected around pipe penetrations and shrinkage cracks in the concrete structure during testing. These leaks posed a challenge that needed to be resolved before installing pumps and pipes in the pump room.

Procedure

To address the issue, a Regional Technical Sales Manager from SealBoss conducted an on-site consultation, recommending the use of SealBoss 1510 Water Stop Foam. This hydrophobic polyurethane resin is designed to expand upon contact with water, forming a closed-cell foam that effectively seals shrinkage cracks and prevents water penetration.

The application involved a high-pressure injection process using the SealBoss P2002 injection system, paired with SealBoss 13-100 AL series injection packers. These packers are ribbed to withstand the high pressure of the injection, ensuring a reliable and durable seal. This approach provided a robust solution for sealing the leaks and protecting the integrity of the concrete structure.

Comprehensive Approach

The combination of on-site consultation, high-quality materials, and specialized equipment highlights SealBoss’s commitment to delivering effective and long-lasting solutions for infrastructure maintenance. The successful application at the Salina wastewater treatment plant is a testament to the effectiveness of SealBoss’s comprehensive approach to concrete repair and waterproofing.

Employed Products:

SealBoss 1510 superior penetration through hairline cracks

SealBoss ® 1510 NSF Approved Water Stop Foam

Shrinkage cracks around pipe penetrations are a common issue in wastewater treatment plants, leading to water seepage from tanks and basins. These leaks pose operational and maintenance challenges and require solutions that comply with strict safety and environmental standards.

SealBoss 1510 Water Stop Foam is a hydrophobic polyurethane resin specially designed to address these issues. Upon contact with water, it expands into a closed-cell, semi-flexible foam that effectively seals cracks and stops leaks. This product is NSF/ANSI/CAN 61 certified, making it safe for contact with drinking water. Its chemical-resistant properties and adjustable reaction times provide contractors with flexibility and long-term reliability, even in challenging environmental conditions.

The NSF/ANSI/CAN 61 certification ensures that SealBoss 1510 meets the highest safety standards for drinking water contact. This certification is vital for projects involving water treatment plants, containment structures, and other systems where water safety is a priority. It guarantees that the product will not leach harmful contaminants into the water supply, safeguarding public health and complying with regulatory requirements.

SealBoss is committed to providing safe and effective waterproofing solutions. With a history of serving the industry since 1988, SealBoss products are trusted by contractors, architects, and engineers worldwide. Our Full System Solutions include a comprehensive range of injection accessories, ensuring seamless integration and support throughout every stage of the injection process.

By choosing SealBoss®, you gain access to high-quality, certified materials and reliable technical support from a single, dependable source. This commitment to safety, durability, and efficiency makes SealBoss 1510 Water Stop Foam an essential choice for infrastructure repair and maintenance.

Related Super Low Viscosity SealBoss Chemical Injection Grouts:

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