A dry shake topping is applied by spreading a dry blend of cement, fine aggregate, admixtures and sometimes pigments over the top of a concrete slab whilst it is curing. It relies on the bleed water from the slab in order to hydrate and if there is not enough bleed water present, there is a high risk of delamination. It is typically blended in a factory and come in bags ready to be applied, typically with a mechanical topping spreader.
Some reasons for using dry shake toppings are:
If a pigment is used, the final colour of a dry shake topping will not turn out as bright or uniform in colour as a resin or paint coating. The appearance of small laboratory samples will not be reflective of the whole finished floor. Usually, if a light coloured pigment is used, it will give the floor improved light reflectivity.
A dry shake topping can be wholly or partially removed by grinding.