FAQ

Do we really believe in E-Crete?

The first questions usually asked about E-Crete are ‘Does this product have what it takes to stack up against OPC-based concrete?’ and ‘Does it really work?’ Our answer is ABSOLUTELY. How can we prove this: with action. Our demonstration facility in Melbourne is sitting on foundations made from E-Crete. Quite literally we stand by, and ON our product.

What are geopolymers made from?

The main difference between geopolymers and normal cement is the chemical reaction pathway. Although the starting materials for both materials are similar, the chemical activation step of geopolymerisation changes the nature of the final material. Therefore, it is little surprise that the finished product looks and performs in a similar manner, just that the chemical reaction pathway to get there is different. For more information see our  research section.

How do you make a geopolymer?

In most cases of geopolymerisation, the raw materials containing silicon and aluminium react simultaneously upon contact with an activator, and are then transformed into new geopolymeric gel by complex reactions. By understanding how different materials will react, Zeobond Pty Ltd can control this transformation process and produce a material with predictable properties. For further information see our research section.

Can geopolymers be made at ambient temperature?

Geopolymers can be made at ambient temperatures, in the exact same ways as ordinary cement and concrete and using the same equipment. This means that anyone can use geopolymers by using similar techniques and people as for cement-based concrete. In addition, the setting time of geopolymers can be manipulated much in the same way as cement-based concrete.

How durable are geopolymers?

Two of the main mechanisms of concrete degradation are sulphate and chloride attack. Geopolymeric concretes have long been noted to have high resistance to these chemical attacks which are associated with ageing. The lower level of calcium in geopolymers compared to OPC is generally beneficial for sulphate resistance, as the formation of the expansive compounds responsible for sulfate degradation of OPC generally requires the presence of significant levels of available calcium.

One of the main reasons why old concrete structures fail is due to corrosion of steel reinforcement embedded in the concrete. The permeability of the geopolymeric binder phase has recently been shown to be lower than that of Portland cements. The main benefit of this low permeability is the reduction of chloride permeability, which reduces the rate of chloride attack on steel reinforcing, thereby increasing the lifespan of the material. For further information see our  research section.

Do geopolymers take longer to cure?

Generally when high volumes of ash and slag are used to replace OPC in concretes the curing of the concrete is adversely affected. For instance, these blended concretes generally have low early strength, take a long time to achieve an initial set, and do not achieve their nominal strength after 28 days. E-Crete avoids these negative effects associated with use of slag and ash by incorporating Zeobond’s proprietary technology and processes. In fact, E-Crete can achieve identical or even better strength development profiles than a 100% OPC concrete. In addition the shrinkage of E-Crete is similar or less than SCM blends and has a very low heat generation which results in only a few degrees temperature rise in large volume slabs. These traits of E-Crete lend themselves to use in applications where both speed and high quality are paramount.

What can you use geopolymers for?

E-Crete looks and performs similarly to normal concrete. In fact, if you didn’t know, your probably couldn’t even tell it doesn’t have any cement in it. E-Crete can be used in most applications where concrete is used today, for example ready-mix, house slabs, foot paths, driveways, pre-cast products like bricks, blocks, pavers and panels. E-Crete also has some special and unique properties which mean it performs very well under aggressive conditions including fire and acidic environments. Some geopolymers perform so well under fire that they can be used as a refractory! Go to our products page for more information or contact us at info@zeobond.com for more information or with a specific enquiry regarding E-Crete products.