With Mexico still in need of a bigger drinking water supply, the Mexican government’s national water agency, Comisión Nacional del Agua (CONAGUA), proposed the creation of a new storage dam in Jalisco, Mexico. Known as the Zapotillo Dam, this project was designed to store enough water so that it could provide 2,000 L per second to parts of Guanajuato and Jalisco. It would improve the lives of around 2.3 million inhabitants, giving more of the population better access to water they could drink safely.
It would also mean that millions of inhabitants would be relying on this storage dam for healthier living. If it ever broke down and needed repairs, many would be without the water they need. With that in mind, CONAGUA’s construction team wanted to ensure the dam’s service life would last as long as possible.
To make that happen, they knew that the dam’s concrete would need to be durable and watertight enough to continually withstand the erosive forces of the surrounding water. It’s why they chose to use roller-compacted concrete. After all, such concrete is made of a drier mix that’s stiff enough to require being compacted by vibratory rollers, showing just how high a compressive strength, flexural strength, shear strength, and density it generally has. That allows it be very durable and even abrasion-resistant, which is why it has quickly become popular in dam construction.
Such features all depend on the materials in a concrete mix, however, and unfortunately, CONAGUA’s construction team had to work with mostly fine aggregates for their mix. That left their roller-compacted mix at a disadvantage. With mainly fine aggregates in the mix, their particular roller-compacted concrete would not meet the project’s compressive strength requirements. It was a concern that had the team worried for how durable and watertight the Zapotillo Dam would be once fully built.
To eliminate their concern, CONAGUA’s construction team sought out solutions that could improve the compressive strength and overall durability of their concrete. That led them to sourcing three key additional components for their concrete mix: KIM, Hard-Cem, and a rheological modification.
With KIM, the construction team’s concrete would reap the benefits of having an award-winning waterproofing admixture that’s been certified by NSF to be safe with potable water. The concrete would become permanently watertight and safe from any waterborne contaminants. And it would all be thanks to KIM’s unique Krystol® technology. Designed to disperse throughout the concrete mix during batching, this technology would imbue the concrete with the ability to chemically react in the presence of water and unhydrated cement particles. As a result, even the slightest presence of water would allow the concrete to react to form solid interlocking crystals, which would fill up the capillary pores and micro-cracks of the concrete. That would ensure that the water would not be able to pass through the concrete and that the concrete itself could self-seal hairline cracks even under heavy hydrostatic pressure.
Then, with the addition of Hard-Cem, the concrete would gain a more durable and resilient cement paste. Without it, the cement paste would remain the weakest element of the concrete as it usually has a microstructure that’s vulnerable to abrasion, erosion, and tension. Hard-Cem corrects that by giving the concrete its own unique metal-mineral microstructure that when embedded throughout cement paste, imparts high durability against abrasion, erosion, and impact. It’s a process that can double the wear life of the concrete and ensure that it remains highly resistant to wear and tear, which also reduces the need for maintenance and repair work. That in turn minimizes how much carbon-intensive cement is required, lowering the lifetime carbon footprint of the dam.
All of which when combined with KIM and the rheological modification would make up for the original concrete mix’s reduced compressive strength while giving it additional waterproofing and abrasion- and erosion-resistant features. Recognizing this, CONAGUA’s construction team put these key components to use, allowing the team to construct a highly durable dam that will be able to supply millions with drinkable water.
Krystol Internal Membrane (KIM) is a hydrophilic crystalline admixture used to create permanently waterproof concrete.
Hard-Cem is an Integral Hardening Admixture used to increase Abrasion and Erosion resistance of concrete. Hard-Cem is added to the concrete at the time of batching to increase the hardness of the concrete and extend concrete wear life. It outperforms and overcomes deficiencies of labor intensive surface applied hardeners, and is used to enhance durability...