Radcon#7 is an advanced waterproofing impregnation system designed to make already cast structural concrete watertight. Unlike conventional solutions, Radcon#7 is not a surface coating, admixture, crystal growth, or water repellent. It is a biochemically modified solution that is simply spray-applied to cured concrete. This innovative product penetrates deeply into the concrete, reacting to form a subsurface barrier that waterproofs pores, capillaries, and cracks. By doing so, it protects steel reinforcement from water and contaminants, enhancing the concrete’s self-healing capabilities and long-term durability. With over 30 years of successful use in critical bridge structures, Radcon#7 is effective for both new and existing structures, addressing issues related to premature failure and extending the lifespan of bridges and highways.
The Concept of Radcon#7
To understand how Radcon#7 works, think about the function of the human body. Our skin prevents water from entering while allowing moisture vapour to escape, maintaining a balance crucial for long-term performance. Similarly, concrete tends to “sweat” in hot and humid climates, making vapour permeability essential for any waterproofing system. The product effectively stops water and contaminants from penetrating the concrete and attacking the steel reinforcement, but crucially, it allows “out-gassing,” enabling moisture vapour to escape. Unlike other surface membranes that fail to permit out-gassing and delaminate easily, this product ensures a durable solution.
The product possesses a self-healing ability akin to the human body’s response to cuts and wounds. When moisture enters through a crack in the concrete, Radcon#7 reacts to seal it with a gel complex, similar to how blood clots to heal cuts. This unique property means that it remains active within the concrete, ready to respond whenever needed. If a crack develops later due to shrinkage or thermal movement, Radcon#7 is drawn to the moisture, sealing the crack and continuing to reseal new cracks throughout the concrete’s lifespan. This feature enables Radcon#7 to guarantee long-term watertight concrete, unlike any other waterproofing system.
Over time, the gel complex hardens (mineralizes) to form a strong, stable calcium carbonate material, similar to limestone, acting as a space filler. This hardened material remains ready to reform the gel whenever necessary. Radcon#7’s ability to form and re-form a flexible gel complex allows it to accommodate thermal movement, which causes concrete structures to expand and contract, particularly in climates with significant day/night and seasonal temperature variations. This adaptability sets Radcon#7 apart from many other waterproofing systems, where thermal movements often lead to premature failure. It can seal existing cracks up to 2.00 mm in diameter and reseal cracks up to 0.30 mm, ensuring the continued integrity and longevity of concrete structures treated with the product.
Properties of Radcon#7
- Colourless, clear to slightly opaque, odourless, soapy feel
- Flash point: no true flash – boils at 101°C
- Non-toxic & biodegradable
- Auto ignition temperature: N/A (non-explosive)
- Non-volatile solids: 27.7%
- Viscosity: 14.3 centipoise or 0.1172 Stokes
- Specific gravity at 25°C: 1.225
- Elements: Na, Si, Fe, Ni, Cu, Zn, Zr, modified sodium silicate (major constituent)
- 0.0% volatile out-gassing (VOG)
- Contains no hazardous chemicals
Advantages of Radcon#7
- Not a membrane therefore zero debonding risk or UV exposure failure.
- Permanently seals existing cracks up to 2 mm.
- Reseals future cracks up to 0.3 mm post-application.
- Maintains seal under thermal stress.
- Compatible with hot asphalt.
- No protective layer needed; rail ballast can be laid directly.
- Strong bond: no loss between asphalt and deck.
- Fast application, allowing project fast-tracking.
- Covers 500 sq. metres per man per day with a 3-man team.
- Wide application window, including monsoon season.
- 100% trafficable: no protection required, asphalt can be directly applied.
Radcon#7 COMPARISON VS TRADITIONAL SURFACE MEMBRANE SYSTEMS
| PERFORMANCE | RADCON #7 | TRADITIONAL SYSTEMS | REMARKS |
|---|---|---|---|
| Lifetime waterproofing | Once applied RF#7 reacts with the concrete and becomes part of the structure. It lasts the life of the structure. | Traditional membranes will typically last for a maximum of 10 years | Lifetime cost benefit. More environmentally beneficial solution |
| Length of warranty | 20-year warranty is issued as standard | Generally, a max of 5-10 years | Longest warranty |
| No further maintenance | One time application will last the life of the structure | Usually has to be redone at reasonably regular intervals. | Lifetime cost & disruption benefit |
| Seals cracks up to 2.00mm | Existing cracks up to 2.00mm can be treated with RF#7 without preparation, as the material penetrates in the cracks and seals it. | No crack sealing ability with surface membranes. | RF#7 fixes faults in the concrete rather than covers them. |
| Will seal future hairline cracks on contact with water | Any cracks that appear in the future which are not due to structural failure and within a certain width, will be resealed by the material as it remains active in the concrete. | Any cracks which appear after application may cause the coating material to crack as it is rigid material. The rigid nature of crystals in the integral crystalline solutions cannot maintain a watertight seal if crack propagates further or if new cracks appear | RF#7 is the only solution that can permanently seal cracks. Durability is guaranteed |
| Delamination | Not possible – RF#7 stops the ingress of moisture but still enables the moisture vapor to escape (rather like the human skin). Allows 84.1% moisture vapor permeability. | Often fail prematurely because of issues with moisture entrapped causing delamination. | Concrete “sweating” is particularly relevant in climates like India |
| Increases concrete surface hardness | Increases hardness from 6 to 8 on the Mohs scale (same hardness as granite) – more resistant to abrasion. | Have no effect on the original concrete surface. | RF#7 enhances the trafficability of concrete |
| No requirement for a topping coat | RF#7 does not need any protection against abrasion or UV | A topping coat is required on almost all membranes to protect them | RF#7 has potential to save cost, time & weight as a result. |
| Thermal stress | RF#7 forms a flexible gel complex in cracks making it able to accommodate thermal movement to maintain a waterproofing seal. | Rely on elongation performance properties in the membrane to “stretch” | RF#7’s ability to form a gel in each crack makes it more accommodating to thermal movement. |
| Speed of application | Forgiving and easy to apply – can achieve >7,000 m2 per day. Single coat application | 100m2 per day (approximate – depending on membrane type, some can be more) | Speeds the overall project, potentially saving crores |
| Can be damaged during application | No | Yes | |
| Trafficable during application | No damage if vehicles drive on it immediately. Can open to traffic within 6 hours of application. | – Only plant & equipment with rubber tyres may drive on material. – Rollers not permitted directly on waterproof system. – Regular inspection of plant & equipment tyre treads to ensure any embedded hard objects removed. | Much more accommodating for managing the impact of lane closures on road users |
Radcon#7 for Bridge Deck and Raised Highway Applications
Radcon#7 offers significant benefits for bridge deck and raised highway applications. It operates inside the concrete, making it resistant to damage from traffic and minimizing disruption during and after construction. This internal action enhances the concrete’s surface hardness, helping it withstand the wear caused by direct trafficking. Unlike surface membranes, Radcon#7 requires no protective screed or coating and remains unaffected by UV exposure. Its compatibility with various surface layers, including hot asphalt at +165°C, further adds to its utility. Radcon#7 can be trafficked within 5 to 6 hours after the first watering, facilitating the quick reopening of lanes during maintenance programs.
Applications Method and Proven performance history of over 30 years in diverse climatic
Despite requiring a level of technical competence, Radcon#7 is easy to apply, with application rates exceeding 7000 m² per day in prepared areas. The effectiveness of the application can be verified by pondering the treated area, and the process is simple and requires low skill, though supervision is essential.
The product has been used 30 years of use in diverse climatic conditions, including:
- Hot and humid climates like Vietnam, Malaysia, Singapore, Sri Lanka, and Bangladesh, with consistent use in Japanese-funded projects.
- Cold climates with freeze-thaw cycles, such as Norway, where it has been used by railway authorities for over 15 years.
It has been extensively tested with 137 product tests and certifications in 20 countries, over 12 million square metres of Radcon#7 have been applied and are under warranty, including approximately 3 million bridge decks, covering around 4 million square metres.
Conclusion
Radcon#7 represents a significant advancement in waterproofing technology, offering a durable and efficient solution for protecting concrete structures. Its deep penetration and unique ability to self-heal ensure long-lasting performance and resilience, especially in challenging environments. With a proven track record spanning over three decades, this innovative system not only enhances the integrity and lifespan of infrastructure but also provides substantial cost and time savings, making it an invaluable product for construction, repairing and maintenance of critical structures like bridges and highways.
About Author
Mike Glover is the Commercial Head for Radcrete in India, bringing over 20 years of international experience, predominantly in Asia and the Middle East. Renowned for his versatility and success in multicultural environments, he excels in creating value through his adaptable, positive, and forward-thinking approach. His extensive career includes senior executive and leadership roles, as well as hands-on experience in functional and front-line operational capacities. His strong track record in project management underscores his reliability and strategic insight.
