In order to meet the demands of its specialty concrete customers in the civil engineering sector, Imerys Aluminates has innovated heavily, producing a wide range of binders, aggregates and technical solutions. These products are designed to meet the needs of high performance special concrete technology in applications such as surfaces/lining, repair or construction requiring short turneround times.
High-performance technology for aggressive environments
Calcium aluminate concretes have specific properties that correspond to key trends in the construction industry. Continually evolving, their technology is constantly improving and raising performance levels in:
Their durability in aggressive environments and their maintenance turnaround time both contribute to the reduction of construction costs in areas such as materials protection, repair and maintenance. The cost of the material is less than its value in reducing the overall cost of construction through better performance properties.
Since CIMENT FONDU®, the first calcium aluminate cement, witch was patented in 1908 by the firm P&A Pavin de Lafarge, Kerneos has constantly developed technology in calcium aluminate cement (also known as CAC or aluminous cement) in order to provide a complete range of products for both "surface concrete" and "rapid concrete" applications.
Whenever infrastructure is exposed to harsh conditions under certain operating environments - especially in heavy industries such as steel manufacturing, petrochemical or aluminium production - CAC concrete provides a protective surface increasing the durability through protection against:
Whether it is for new construction or for carrying out repairs, maintenance turnaround time is a significant, not to say critical, factor. The rapid strength development of CAC concretes allows for maintenance turnaround times of just a few hours after placing:
Because their constituents and their production processes are different from those of Portland cement, calcium aluminate cements (also called CAC or aluminous cements) produce concretes that achieve exceptional performance which is often impossible to attain with current Portland cement-based concrete technology.
Calcium aluminate concretes supplement traditional ranges of concrete by offering the following properties:
|very fast hardening: compressive strength in under 3 hours up to 20 MPa|
|controlled wet-edge time: up to a few hours, depending on the mix and admixtures|
|very high resistance to wear caused by abrasion, erosion, pitting and impact|
|resistance to high temperatures (1,100° C) and to thermal shock caused by both high and low temperatures|
|hardening even in cold weather (as cold as -10° C under certains conditions)|
exceptional resistance to biogenic corrosion (sewage systems) and diluted acids: pH ≥ 4, even pH ≥ 3.5 with the use of ALAG® synthetic aggregates.
The range of products available for civil engineering specialty concrete applications currently consists of four major families.
To meet needs for reactivity, flow rate, colour and resistance to physical chemical aggression, Kerneos offers a range of calcium aluminate cement products covering a wide range of chemical and mineralogical components.
The choice of a binder for specialty concrete depends on the technical specification.
When the situation so justifies, tailor-made binders can be developed.
2) Synthetic aggregates
To respond to the most extreme abrasion, corrosion and thermal shocks, aluminous cement concretes are formulated using ALAG® synthetic aggregates. These are extremely hard and offer exceptional chemical affinity with aluminous cements. They make it possible to produce very high-performance concrete.
3) Pre-mixed mortar and concrete
Offering easy-to-use procedures and reliable results, the FONDAG® and FONDUCRETE® ranges are high-performance ready-to-use mortars and concretes - users only have to add the mixing water.
4) Solution systems for the ready-mix concrete industry
Kerneos has developed "solution systems" for ready-mix concrete manufacturers. These systems combine a specific binder, appropriate admixtures and an application procedure that produces the desired result.
The objective is to obtain calcium aluminate concrete which is compatible with the practices of the ready-mix concrete industry yet maintains the application qualities of CAC concrete (sufficient wet-edge time, a flow rate allowing the application of large volumes and reliable results).
Those primarily concerned by this range are concrete producers wishing to broaden their own range of products.
Find out more about Kerneos products for civil engineering applications: