A more efficient and cost-effective alternative to moist curing shotcrete

Spray-Lock Concrete Protection’s SCP technologies are providing an efficient and cost-effective alternative for curing shotcrete.

Curing plays an important role in developing the desired durability properties in this concrete or mortar that is pumped through a hose and sprayed at a high velocity against a surface area. Its consistency, or “slump” is usually dryer than conventional concrete so that it can adhere to slopes and vertical surfaces.

Moist curing has traditionally been regarded as the “gold standard” for maintaining moisture levels in both conventional concrete and shotcrete. However, it can be difficult to maintain correctly, while also presenting an array of other challenges relating to safety and the environment.

Carl White, Managing Director of SprayLock Africa, says that the colloidal silica-based product is spray-applied to the surface of the shotcrete where it penetrates the available capillary pore space to react with available alkalis to form primarily calcium silicate hydrate (C-S-H).

“This is the same reaction product that cement and water produces to provide concrete with most of its strength and durability properties. By filling the accessible pores, SCP products hold water in the shotcrete that the cement needs. It also keeps external water out of the matrix as an important part of any shotcrete waterproofing solution,” White says.

This proprietary application of colloidal silica technology that was developed in the United States has proven to greatly reduce permeability of a variety of traditional concrete designs, including shotcrete, over more than a decade.

By making water that would normally evaporate at early stages available for continued hydration, SCP significantly improves the compressive strength and reduces drying shrinkage of concrete – even when compared to moist-cured samples.

SprayLock Africa is the African representative for SCP products in Africa.

The company continues to demonstrate its commitment to quality via its many control systems in the storage and delivery processes to ensure the timeous delivery of stock to customers in its many African territories.
These are supported by Spraylock Concrete Protection’s own manufacturing and associated processes that are certified to the ISO 9000 quality management system.

Spraylock Africa has also partnered local professionals who provide expert advice and robust technical support to professional teams using SCP technologies.