SILICO Crete

Surface preparation:
surface preparation must result in the removal of all unsound concrete and all contamination that hinders the adhesion or performance of silico crete. A clean, hard, rough surface should be provided.
The shape and depth of the repair should also be considered. Although silico crete repair compound is designed to adhere and gain strength even in thin sections, many types of structural repairs are better accomplished when edges are saw cut.
Reinforcement steel bars:
expose fully any corroded steel in repair and remove all loose scales and corrosion deposits around its full circumference. Steel should be cleaned to achieve a bright condition. Use a rust remover as a rust-converting primer for rust-free rebars. Where the reinforcing bars are corroded, cut back the concrete from the exposed rebar to at least 20mm behind the reinforcing bar. Remove the corrosion from and around the reinforcing bar. Then, coat the rebar with anti-corrosion products to protect it from further corrosion.
Replace the affected part of the rebar if its diameter, after cleaning, is reduced by 18% to 20% of the original diameter. Apply two coats of suitable bond coat, ensuring that all general and specific application guidelines for passivating steel reinforcement are followed.
Substrate priming:
surfaces should be dampened with clean water for at least 20 minutes before patching. Any excess water should be removed before priming the surface with a suitable bond coat as a bonding agent.
Mixing:
silico crete is a one-component product that only requires the addition of water on-site. Ensure that silico crete is thoroughly mixed in a forced-action mixer. The dry mortar should be slowly added to the water and mixed thoroughly until a homogeneous mortar is achieved.
Slow paddle mixers or drum mixers are suitable and mixing should take place for at least 3 minutes to ensure a smooth, homogeneous consistency. Allow the mix to rest for 2-3 minutes, then remix for a minute or two before applying.
Hand mixing may be allowed if the quantity of mortar required is very small, but care should be taken to thoroughly mix the mortar into a “dough-like” consistency, with at least 5 minutes of mixing.
Application:
apply the mixed silico crete to the prepared surface with a gloved hand or trowel. Thoroughly compact the mortar on the “tacky” bonding coat, ensuring no air pockets remain. The working time (pot life) of silico crete is about 30 minutes at +30°c.
If several layers are to be applied, the first/previous coat must be scratched/keyed and must be sufficiently set/hardened before applying the bonding coat and subsequent silico crete coat.
Curing:
avoid rapid drying, but dry cure. When working under hot, dry, or windy conditions, surfaces may require misting or plastic film protection to prevent rapid drying. This is particularly important when large or deep patches are exposed to direct sunlight.
Alternatively, a curing compound can be used over the freshly applied surface of silico crete.